Alpha-gal syndrome (AGS) is an IgE-mediated allergy to the mammalian oligosaccharide galactose-alpha-1,3-galactose (alpha-gal), a glycan present on the glycoproteins and glycolipids of non-primate mammalian tissue. Unlike most food allergies, AGS is directed against a carbohydrate rather than a protein, and sensitization is acquired after tick bites (notably the lone star tick Amblyomma americanum in the United States) that introduce alpha-gal and prime an anti-alpha-gal IgE response. Ingestion of mammalian ("red") meat and mammalian-derived products then triggers allergic reactions ranging from urticaria and angioedema to gastrointestinal distress and anaphylaxis. Characteristically the reaction is delayed 2-6 hours after ingestion; the leading explanation is that the alpha-gal epitope is carried substantially on glycolipids that are absorbed and enter the circulation slowly. Immediate (non-delayed) reactions occur on first exposure to the monoclonal antibody cetuximab, whose Fab region carries alpha-gal.
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name: Alpha-gal Syndrome
creation_date: "2026-07-05T00:00:00Z"
description: >-
Alpha-gal syndrome (AGS) is an IgE-mediated allergy to the mammalian
oligosaccharide galactose-alpha-1,3-galactose (alpha-gal), a glycan present on
the glycoproteins and glycolipids of non-primate mammalian tissue. Unlike most
food allergies, AGS is directed against a carbohydrate rather than a protein,
and sensitization is acquired after tick bites (notably the lone star tick
Amblyomma americanum in the United States) that introduce alpha-gal and prime
an anti-alpha-gal IgE response. Ingestion of mammalian ("red") meat and
mammalian-derived products then triggers allergic reactions ranging from
urticaria and angioedema to gastrointestinal distress and anaphylaxis.
Characteristically the reaction is delayed 2-6 hours after ingestion; the leading
explanation is that the alpha-gal epitope is carried substantially on glycolipids
that are absorbed and enter the circulation slowly. Immediate (non-delayed)
reactions occur on first exposure to the monoclonal antibody cetuximab, whose Fab
region carries alpha-gal.
category: Complex
disease_term:
preferred_term: alpha-gal syndrome
term:
id: MONDO:0100001
label: alpha-gal syndrome
parents:
- Allergic disease
pathophysiology:
- name: Tick-bite sensitization to alpha-gal
description: >-
Bites from certain hard ticks (Amblyomma americanum in the US; Ixodes
holocyclus in Australia; Ixodes ricinus in Europe) introduce
galactose-alpha-1,3-galactose into the host and drive class-switching to an
anti-alpha-gal IgE response. Repeated tick exposure is the principal route of
sensitization, distinguishing AGS from protein food allergies.
cell_types:
- preferred_term: IgE plasmablast
term:
id: CL:0000950
label: IgE plasmablast
biological_processes:
- preferred_term: immunoglobulin production
term:
id: GO:0002377
label: immunoglobulin production
modifier: INCREASED
evidence:
- reference: PMID:21453959
reference_title: "The relevance of tick bites to the production of IgE antibodies to the mammalian oligosaccharide galactose-α-1,3-galactose."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Prospective studies on IgE antibodies in 3 subjects after tick bites
showed an increase in levels of IgE to alpha-gal of 20-fold or greater."
explanation: Prospective human data show tick bites drive a large rise in
anti-alpha-gal IgE, establishing tick exposure as the sensitizing route.
- reference: PMID:19413526
reference_title: "An association between tick bite reactions and red meat allergy in humans."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Twenty-five patients living in a tick-endemic region of Sydney, New
South Wales developed red meat allergy after experiencing large local
reactions to tick bites."
explanation: The original Australian case series linked tick-bite reactions to
subsequent red meat allergy, supporting tick-driven sensitization.
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "in subjects with IgE to alpha-gal there appears to be proliferation of
a subset of plasmablasts in response to tick extract that was not present in
control subjects"
explanation: Tick-antigen-driven plasmablast proliferation in alpha-gal-sensitized
subjects supports the humoral (IgE plasmablast) arm of sensitization.
- reference: PMID:38390396
reference_title: "Tick bite-induced alpha-gal syndrome and immunologic responses in an alpha-gal deficient murine model."
supports: SUPPORT
evidence_source: MODEL_ORGANISM
snippet: "Gene expression analysis revealed that Am. americanum bites direct
mouse immunity toward Th2 and facilitate host sensitization to the α-gal
antigen."
explanation: In an alpha-gal-deficient (AGKO) mouse model, lone-star tick bites
drive Th2 polarization and alpha-gal sensitization, experimentally recapitulating
the human tick-sensitization mechanism.
downstream:
- target: Alpha-gal-specific IgE and effector-cell sensitization
causal_link_type: DIRECT
description: Tick-induced anti-alpha-gal IgE arms mast cells and basophils,
establishing the sensitized effector state required for reactions on re-exposure.
- name: Alpha-gal-specific IgE and effector-cell sensitization
description: >-
Anti-alpha-gal IgE binds the high-affinity receptor FcepsilonRI on mast cells
and basophils. On re-exposure to alpha-gal-bearing mammalian glycoproteins and
glycolipids, cross-linking of receptor-bound IgE triggers mast cell and
basophil degranulation, a type I (immediate) hypersensitivity response.
cell_types:
- preferred_term: mast cell
term:
id: CL:0000097
label: mast cell
- preferred_term: basophil
term:
id: CL:0000767
label: basophil
biological_processes:
- preferred_term: type I hypersensitivity mediated by mast cells
term:
id: GO:0002558
label: type I hypersensitivity mediated by mast cells
modifier: INCREASED
- preferred_term: mast cell degranulation
term:
id: GO:0043303
label: mast cell degranulation
modifier: INCREASED
evidence:
- reference: PMID:19070355
reference_title: "Delayed anaphylaxis, angioedema, or urticaria after consumption of red meat in patients with IgE antibodies specific for galactose-alpha-1,3-galactose."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "IgE antibodies to galactose-alpha-1,3-galactose (alpha-gal), a
carbohydrate commonly expressed on nonprimate mammalian proteins, are capable
of eliciting serious, even fatal, reactions."
explanation: Establishes anti-alpha-gal IgE against a nonprimate mammalian
carbohydrate as the effector antibody capable of triggering allergic reactions.
downstream:
- target: Delayed anaphylaxis from glycolipid-borne alpha-gal
causal_link_type: DIRECT
description: On ingestion of mammalian meat, IgE cross-linking on sensitized
effector cells drives the delayed systemic allergic reaction.
- target: Cetuximab immediate hypersensitivity
causal_link_type: DIRECT
description: The same sensitized anti-alpha-gal IgE state mediates immediate
hypersensitivity when cetuximab presents alpha-gal intravenously.
- name: Delayed anaphylaxis from glycolipid-borne alpha-gal
description: >-
Because much of dietary alpha-gal is carried on glycolipids, absorption,
processing, and presentation of the allergen are slow, so systemic mediator
release and clinical symptoms are characteristically delayed 2-6 hours after
ingestion of mammalian meat, in contrast to the rapid reactions typical of
protein food allergens.
biological_processes:
- preferred_term: histamine secretion by mast cell
term:
id: GO:0002553
label: histamine secretion by mast cell
modifier: INCREASED
evidence:
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Given that alpha-gal is present on both glycoproteins and glycolipids
(including chylomicrons), it is our belief that the most likely explanation for
the delay in symptoms is due to a delay in the appearance of the antigen in the
circulation."
explanation: Supports the glycolipid/chylomicron model explaining why reactions
are delayed several hours after mammalian meat ingestion.
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The implication is that LDL particles with alpha-gal on the surface can
cause mast cell mediator release, but only in individuals with IgE Ab to
alpha-gal."
explanation: Links lipoprotein-borne alpha-gal to IgE-dependent mast cell
mediator release, the mechanistic basis of the delayed reaction.
- name: Cetuximab immediate hypersensitivity
description: >-
The cetuximab Fab region carries an alpha-gal-bearing N-glycan. In
pre-sensitized individuals, first infusion of cetuximab produces immediate
(non-delayed) hypersensitivity, the observation that first linked
anti-alpha-gal IgE to clinical anaphylaxis.
biological_processes:
- preferred_term: mast cell degranulation
term:
id: GO:0043303
label: mast cell degranulation
modifier: INCREASED
evidence:
- reference: PMID:18337601
reference_title: "Cetuximab-induced anaphylaxis and IgE specific for galactose-alpha-1,3-galactose."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The IgE antibodies were shown to be specific for an oligosaccharide,
galactose-alpha-1,3-galactose, which is present on the Fab portion of the
cetuximab heavy chain."
explanation: The landmark study showing pre-existing anti-alpha-gal IgE binds the
alpha-gal glycan on the cetuximab Fab, causing immediate hypersensitivity.
phenotypes:
- name: Meat allergen allergy
description: Allergy to mammalian ("red") meat and mammalian-derived products.
phenotype_term:
preferred_term: Meat allergen allergy
term:
id: HP:0410330
label: Meat allergen allergy
evidence:
- reference: PMID:19070355
reference_title: "Delayed anaphylaxis, angioedema, or urticaria after consumption of red meat in patients with IgE antibodies specific for galactose-alpha-1,3-galactose."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "We sought to determine whether IgE antibodies to alpha-gal are present
in sera from patients who report anaphylaxis or urticaria after eating beef,
pork, or lamb."
explanation: Documents allergy to mammalian meats (beef, pork, lamb) as the
defining clinical presentation of alpha-gal syndrome.
- name: Delayed anaphylaxis
description: >-
Anaphylaxis occurring characteristically 2-6 hours after ingestion of
mammalian meat.
phenotype_term:
preferred_term: Food-induced anaphylaxis
term:
id: HP:0500095
label: Food-induced anaphylaxis
evidence:
- reference: PMID:19070355
reference_title: "Delayed anaphylaxis, angioedema, or urticaria after consumption of red meat in patients with IgE antibodies specific for galactose-alpha-1,3-galactose."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "These patients described a similar history of anaphylaxis or urticaria
3 to 6 hours after the ingestion of meat and reported fewer or no episodes when
following an avoidance diet."
explanation: Documents the characteristic delayed (3-6 hour) anaphylaxis or
urticaria after mammalian meat ingestion.
- reference: PMID:38193233
reference_title: "Tick bites, IgE to galactose-alpha-1,3-galactose and urticarial or anaphylactic reactions to mammalian meat: The alpha-gal syndrome."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Reactions in AGS are delayed, often by 2-6 h after ingestion of
mammalian meat."
explanation: A recent authoritative review confirms the characteristic 2-6 hour
delay between mammalian meat ingestion and reactions.
- name: Urticaria
description: Delayed-onset hives after mammalian meat ingestion.
phenotype_term:
preferred_term: Urticaria
term:
id: HP:0001025
label: Urticaria
evidence:
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Common complaints include both gastrointestinal symptoms and urticaria"
explanation: Urticaria is a common cutaneous manifestation of alpha-gal reactions.
- name: Angioedema
description: Deep dermal/subcutaneous swelling accompanying reactions.
phenotype_term:
preferred_term: Angioedema
term:
id: HP:0100665
label: Angioedema
evidence:
- reference: PMID:19070355
reference_title: "Delayed anaphylaxis, angioedema, or urticaria after consumption of red meat in patients with IgE antibodies specific for galactose-alpha-1,3-galactose."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Delayed anaphylaxis, angioedema, or urticaria after consumption of red
meat in patients with IgE antibodies specific for galactose-alpha-1,3-galactose."
explanation: Angioedema is among the delayed reactions to red meat in alpha-gal
syndrome.
- name: Pruritus
description: Generalized itching during allergic reactions.
phenotype_term:
preferred_term: Pruritus
term:
id: HP:0000989
label: Pruritus
evidence:
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "the most common symptom reported was itching"
explanation: Itching (pruritus) was the most commonly reported symptom in
alpha-gal reactions.
- name: Abdominal pain
description: Gastrointestinal-predominant reactions may present with abdominal pain.
phenotype_term:
preferred_term: Abdominal pain
term:
id: HP:0002027
label: Abdominal pain
evidence:
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Common complaints include both gastrointestinal symptoms and urticaria"
explanation: Gastrointestinal symptoms are a common presentation of alpha-gal
reactions, sometimes predominating.
- name: Diarrhea
description: Gastrointestinal symptom during reactions.
phenotype_term:
preferred_term: Diarrhea
term:
id: HP:0002014
label: Diarrhea
evidence:
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Many of the patients described nausea, diarrhea or indigestion before a
reaction, however the most common symptom reported was itching."
explanation: Diarrhea is among the gastrointestinal symptoms reported during
alpha-gal reactions.
- name: Nausea and vomiting
description: Gastrointestinal symptom during reactions.
phenotype_term:
preferred_term: Nausea and vomiting
term:
id: HP:0002017
label: Nausea and vomiting
evidence:
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Many of the patients described nausea, diarrhea or indigestion before a
reaction, however the most common symptom reported was itching."
explanation: Nausea is among the gastrointestinal symptoms reported during
alpha-gal reactions.
- name: Increased anti-meat allergen IgE
description: >-
Elevated serum IgE specific for galactose-alpha-1,3-galactose (anti-meat
allergen IgE) is the defining laboratory feature.
phenotype_term:
preferred_term: Increased anti-meat allergen IgE antibody level
term:
id: HP:0410233
label: Increased anti-meat allergen IgE antibody level
evidence:
- reference: PMID:19070355
reference_title: "Delayed anaphylaxis, angioedema, or urticaria after consumption of red meat in patients with IgE antibodies specific for galactose-alpha-1,3-galactose."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Twenty-four patients with IgE antibodies to alpha-gal were identified."
explanation: Identifies patients by the defining laboratory feature of elevated
serum IgE specific for alpha-gal (anti-meat allergen IgE).
biochemical:
- name: Alpha-gal-specific IgE
notes: >-
Serum IgE directed against galactose-alpha-1,3-galactose; the diagnostic
biomarker of AGS, measured by specific IgE immunoassay.
presence: PRESENT
evidence:
- reference: PMID:19070355
reference_title: "Delayed anaphylaxis, angioedema, or urticaria after consumption of red meat in patients with IgE antibodies specific for galactose-alpha-1,3-galactose."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "CAP-RAST testing revealed specific IgE antibodies to"
explanation: Serum specific IgE to alpha-gal (by ImmunoCAP/CAP-RAST) is the
diagnostic biomarker used to identify affected patients.
environmental:
- name: Tick bite
notes: >-
Bites of the lone star tick (Amblyomma americanum) in the southeastern and
eastern United States are the principal sensitizing exposure; Ixodes
holocyclus (Australia) and Ixodes ricinus (Europe) are implicated elsewhere.
evidence:
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "In Europe, Ixodes ricinus has been implicated while in Australia the
relevant tick is Ixodes holocyclus"
explanation: Documents the geographically distinct tick vectors driving alpha-gal
sensitization outside the United States.
- reference: PMID:21453959
reference_title: "The relevance of tick bites to the production of IgE antibodies to the mammalian oligosaccharide galactose-α-1,3-galactose."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "evidence that these IgE antibodies are common in areas where the tick
Amblyomma americanum is common"
explanation: Links the geographic distribution of anti-alpha-gal IgE to the range
of the lone star tick Amblyomma americanum.
- name: Mammalian meat and mammalian-derived products
notes: >-
Beef, pork, lamb, and other non-primate mammalian meat, plus organ meats,
dairy, gelatin, and mammalian-derived medical products (e.g., gelatin
colloids, some vaccines, heparin, bovine/porcine bioprosthetic materials).
evidence:
- reference: PMID:38193233
reference_title: "Tick bites, IgE to galactose-alpha-1,3-galactose and urticarial or anaphylactic reactions to mammalian meat: The alpha-gal syndrome."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "can also involve reactions to visceral organs, dairy, gelatin and other
products, including medications sourced from non-primate mammals"
explanation: Documents that alpha-gal reactions extend beyond muscle meat to
visceral organs, dairy, gelatin, and mammalian-derived medications.
- name: Cetuximab
notes: >-
The anti-EGFR monoclonal antibody cetuximab carries alpha-gal on its Fab
glycan and causes immediate hypersensitivity in pre-sensitized patients.
evidence:
- reference: PMID:18337601
reference_title: "Cetuximab-induced anaphylaxis and IgE specific for galactose-alpha-1,3-galactose."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "In most subjects who had a hypersensitivity reaction to cetuximab, IgE
antibodies against cetuximab were present in serum before therapy."
explanation: Pre-existing anti-alpha-gal IgE explains immediate cetuximab
hypersensitivity on first exposure in sensitized patients.
treatments:
- name: Mammalian meat avoidance
description: >-
Dietary avoidance of mammalian meat and, in more sensitive patients,
mammalian-derived products (dairy, gelatin) is the cornerstone of management.
treatment_term:
preferred_term: dietary mammalian meat food product intake avoidance
term:
id: MAXO:0010052
label: dietary mammalian meat food product intake avoidance
evidence:
- reference: PMID:19070355
reference_title: "Delayed anaphylaxis, angioedema, or urticaria after consumption of red meat in patients with IgE antibodies specific for galactose-alpha-1,3-galactose."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "reported fewer or no episodes when following an avoidance diet"
explanation: Patients had fewer or no reactions on a mammalian-meat avoidance
diet, supporting dietary avoidance as primary management.
- name: Epinephrine
description: >-
Intramuscular epinephrine (adrenaline) auto-injector for treatment of
anaphylaxis; patients at risk should carry one.
treatment_term:
preferred_term: Pharmacotherapy
term:
id: NCIT:C15986
label: Pharmacotherapy
therapeutic_agent:
- preferred_term: adrenaline
term:
id: CHEBI:33568
label: adrenaline
evidence:
- reference: PMID:40312115
reference_title: "Alpha-gal syndrome: Recognizing and managing a tick-bite-related meat allergy."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Allergist referral with injectable epinephrine"
explanation: A management review recommends injectable epinephrine for patients
with severe alpha-gal reactions concerning for anaphylaxis.
- name: Antihistamine therapy
description: Antihistamines for symptomatic relief of cutaneous and mild reactions.
treatment_term:
preferred_term: antihistamine agent therapy
term:
id: MAXO:0000313
label: antihistamine agent therapy
evidence:
- reference: PMID:40312115
reference_title: "Alpha-gal syndrome: Recognizing and managing a tick-bite-related meat allergy."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Prescribe antihistamines for all patients"
explanation: A management review recommends antihistamines for all alpha-gal
syndrome patients.
- name: Tick bite prevention
description: >-
Avoidance of tick bites (protective clothing, repellents, tick checks) to
prevent further boosting of anti-alpha-gal IgE.
treatment_term:
preferred_term: therapeutic avoidance of environmental exposure
term:
id: MAXO:0000053
label: therapeutic avoidance of environmental exposure
evidence:
- reference: PMID:40312115
reference_title: "Alpha-gal syndrome: Recognizing and managing a tick-bite-related meat allergy."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Management focuses on avoiding foods and products that contain alpha-gal
and preventing tick bites."
explanation: A management review identifies preventing tick bites as a core
component of alpha-gal syndrome management.
- reference: PMID:33009122
reference_title: "'Doc, will I ever eat steak again?': diagnosis and management of alpha-gal syndrome."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Long-term management of the condition involves avoidance of both
mammalian food products and tick bites."
explanation: A second review confirms tick-bite avoidance as part of long-term
alpha-gal syndrome management.
mechanistic_hypotheses:
- hypothesis_group_id: tick_salivary_constituent_sensitization
hypothesis_label: Tick-Intrinsic Salivary Constituent Model
status: CANONICAL
description: >-
The anti-alpha-gal IgE response is induced by normal, tick-derived
constituents of tick saliva. Contemporary work supports ticks synthesizing
alpha-gal via their own galactosyltransferases and presenting it, together
with Th2-skewing salivary factors, at the bite site, so the sensitizing
antigen is intrinsic to the tick rather than borrowed.
notes: >-
Promoted from ALTERNATIVE to CANONICAL for the antigen-source question. The
2026 openscientist hypothesis-search report
(kb/hypotheses/Alpha-gal_Syndrome/tick_salivary_constituent_sensitization)
reviewed 80+ primary papers and found convergent support: tick
galactosyltransferases cloned and functionally validated (PMID:30242261),
alpha-gal glycolipids detected directly in Amblyomma americanum saliva by
mass spectrometry (PMID:39053323), feeding-independent alpha-gal in tick
salivary glands (PMID:38741222), and tick salivary gland extract alone
sufficient to induce AGS-like sensitization in AGKO mice (PMID:34034363).
CANONICAL is scoped to the antigen SOURCE only; the downstream IgE
class-switching step for a carbohydrate antigen remains unresolved (see the
disc_ags_ige_class_switch_site knowledge gap).
evidence:
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "That the response is induced by the normal (i.e. tick derived)
constituents of their saliva."
explanation: States the tick-intrinsic salivary-constituent theory as one of the
competing explanations for alpha-gal sensitization.
- reference: PMID:30242261
reference_title: "Tick galactosyltransferases are involved in α-Gal synthesis and play a role during Anaplasma phagocytophilum infection and Ixodes scapularis tick vector development."
supports: SUPPORT
evidence_source: IN_VITRO
snippet: "The α-Gal on tick salivary proteins plays an important role in the
etiology of the α-Gal syndrome."
explanation: Identifies and functionally validates tick galactosyltransferases,
establishing that ticks endogenously synthesize the alpha-gal on their salivary
proteins.
- reference: PMID:38741222
reference_title: "Alpha-Gal, epitope responsible for allergy to red meat, in the Mediterranean tick Hyalomma lusitanicum."
supports: SUPPORT
evidence_source: IN_VITRO
snippet: "The highest concentrations of α-Gal were detected in salivary glands.
Neither sex nor diet influenced the concentration of α-Gal, which seems to
indicate its endogenous production"
explanation: Alpha-gal is concentrated in tick salivary glands independent of
feeding status, indicating endogenous tick production rather than a borrowed
antigen.
- reference: PMID:34034363
reference_title: "Tick salivary gland extract induces alpha-gal syndrome in alpha-gal deficient mice."
supports: SUPPORT
evidence_source: MODEL_ORGANISM
snippet: "Tick salivary gland extract induces alpha-gal syndrome in alpha-gal
deficient mice"
explanation: Pathogen-free tick salivary gland extract alone is sufficient to
induce AGS-like sensitization, isolating the tick salivary constituents as the
sensitizing agent.
- reference: PMID:38390396
reference_title: "Tick bite-induced alpha-gal syndrome and immunologic responses in an alpha-gal deficient murine model."
supports: PARTIAL
evidence_source: MODEL_ORGANISM
snippet: "Gene expression analysis revealed that Am. americanum bites direct
mouse immunity toward Th2 and facilitate host sensitization to the α-gal
antigen."
explanation: The AGKO-mouse model shows lone-star tick bites themselves drive Th2
polarization and alpha-gal sensitization, consistent with a tick-intrinsic route.
- reference: PMID:39053323
reference_title: "Identification of Alpha-Gal glycolipids in saliva of Lone-Star Tick (Amblyomma americanum)."
supports: SUPPORT
evidence_source: IN_VITRO
snippet: "activation of basophils by extracted alpha-gal bound lipids and proteins"
explanation: Mass spectrometry directly identified alpha-gal glycolipids in
Amblyomma americanum saliva, and the extracted alpha-gal-bound lipids/proteins
activated basophils, showing tick saliva carries functionally active alpha-gal.
- hypothesis_group_id: residual_blood_meal_glycoconjugate
hypothesis_label: Residual Mammalian Blood-Meal Glycoconjugate Model
status: DEPRECATED
description: >-
Residual mammalian glycoproteins or glycolipids carried in the tick from a
previous mammalian blood meal are responsible for inducing the anti-alpha-gal
response, i.e. the antigen is borrowed from prior mammalian hosts rather than
made by the tick.
notes: >-
Deprecated. A dedicated 2026 openscientist hypothesis-search for this model
(kb/hypotheses/Alpha-gal_Syndrome/residual_blood_meal_glycoconjugate, 46
papers) returned an explicit REFUTED verdict. The finding of alpha-gal in the
salivary glands of unfed, vegetation-collected ticks independent of diet
(PMID:38741222), the identification of endogenous tick galactosyltransferases
(PMID:30242261), the sufficiency of laboratory-reared tick salivary gland
extract to sensitize AGKO mice (PMID:34034363), and the dog paradox - dogs
express alpha-gal as a self-antigen yet still mount anti-alpha-gal antibodies
after tick bites (PMID:31540167) - collectively refute a borrowed-blood-meal
antigen source as the primary mechanism. Caveat noted by the search: the
diet-independence studies used ELISA rather than high-resolution glycomics, so
a marginal, trace contribution of residual mammalian glycoconjugates cannot be
absolutely excluded, but it is not the primary mechanism. Retained as
DEPRECATED for provenance.
evidence:
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "That residual mammalian glycoproteins or glycolipids are present in the
tick from a previous blood meal, and that they are responsible for inducing the
response to alpha-gal."
explanation: States the residual-blood-meal glycoconjugate theory as a historically
competing sensitization mechanism.
- reference: PMID:38741222
reference_title: "Alpha-Gal, epitope responsible for allergy to red meat, in the Mediterranean tick Hyalomma lusitanicum."
supports: REFUTE
evidence_source: IN_VITRO
snippet: "Neither sex nor diet influenced the concentration of α-Gal, which seems
to indicate its endogenous production"
explanation: Feeding-independent alpha-gal in unfed ticks refutes a borrowed
blood-meal glycoconjugate as the antigen source.
- reference: PMID:31540167
reference_title: "Tick Bites Induce Anti-α-Gal Antibodies in Dogs."
supports: REFUTE
evidence_source: MODEL_ORGANISM
snippet: "non-primate mammals, including dogs, have the ability to synthetize
α-Gal and, thus, their immune system is not expected to naturally generate the
antibodies toward this self-antigen molecule"
explanation: Dogs synthesize alpha-gal as a self-antigen yet still develop
anti-alpha-gal IgG/IgM/IgE after tick bites; if the sensitizing antigen were
residual mammalian (self) alpha-gal from a blood meal, dogs should not respond,
so this refutes the blood-meal source.
- hypothesis_group_id: tick_associated_microorganism
hypothesis_label: Tick-Associated Microorganism Model
status: DEPRECATED
description: >-
The response is induced by another organism present in the tick (e.g.
commensal or pathogenic microbes such as Rickettsia or Borrelia), rather than
by tick or mammalian glycans directly.
notes: >-
Deprecated. A dedicated 2026 openscientist hypothesis-search for this model
(kb/hypotheses/Alpha-gal_Syndrome/tick_associated_microorganism, 51 papers)
returned an explicit REFUTED verdict. Epidemiological studies show no
correlation between alpha-gal sIgE and antibodies to tick-borne pathogens
(PMID:35382677), and pathogen-free tick salivary gland extract alone is
sufficient to sensitize AGKO mice (PMID:34034363), refuting a co-transmitted
microorganism as the primary sensitizer. Caveat noted by the search: even
laboratory "pathogen-free" tick colonies still harbor obligate endosymbionts
(e.g. Francisella-like organisms), so a minor, untested modulatory role for
tick-associated microbiota cannot be formally excluded - but because ticks
synthesize alpha-gal endogenously and the salivary immune context (not the
antigen source) drives clinical disease, this does not rescue the model.
Retained as DEPRECATED for provenance.
evidence:
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "That the response is induced by another organism that is present in the
tick."
explanation: States the tick-associated-microorganism theory as a historically
competing sensitization mechanism.
- reference: PMID:35382677
reference_title: "Sensitisation and allergic reactions to alpha-1,3-galactose in Podlasie, Poland, an area endemic for tick-borne infections."
supports: REFUTE
evidence_source: HUMAN_CLINICAL
snippet: "confirm that the pathogens carried by ticks we examined for do not seem
implicated in this immune response"
explanation: The absence of correlation between alpha-gal sIgE and tick-borne
pathogen exposure refutes a co-transmitted microorganism as the antigen source.
discussions:
- discussion_id: disc_ags_ige_class_switch_site
prompt: >-
Where and how does class-switching to anti-alpha-gal IgE occur after a tick
bite - within classical germinal centers, or locally in the skin outside
germinal centers?
kind: KNOWLEDGE_GAP
status: OPEN
attaches_to:
- pathophysiology#Tick-bite sensitization to alpha-gal
rationale: >-
The anatomical site and T-cell dependence of the switch to alpha-gal-specific
IgE are unresolved and bear on why this carbohydrate elicits a durable IgE
(rather than IgG/IgM) response and why the response wanes with tick avoidance.
evidence:
- reference: PMID:25747720
reference_title: "The alpha-gal story: lessons learned from connecting the dots."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "there is a real possibility that the IgE response to alpha-gal involves
switching that occurs outside germinal centers and it is possible that the skin
is the site of such a switch"
explanation: The review frames the site of IgE class-switching as an explicit open
mechanistic question.
- discussion_id: disc_ags_agko_mouse_translational_fidelity
prompt: >-
Does the alpha-gal-deficient (AGKO) mouse - in which lone-star tick bites
raise total IgE and alpha-gal IgG1 and pork challenge causes a body-temperature
drop - faithfully model the human IgE-mediated, glycolipid-delayed anaphylaxis
of alpha-gal syndrome?
kind: HUMAN_MODEL_MISMATCH
status: OPEN
attaches_to:
- pathophysiology#Tick-bite sensitization to alpha-gal
- pathophysiology#Delayed anaphylaxis from glycolipid-borne alpha-gal
rationale: >-
Humans are naturally alpha-gal-negative and mount an IgE response, whereas the
AGKO model's alpha-gal-specific response is predominantly IgG1 and its readout
is hypothermia rather than the characteristic 2-6 hour delayed,
glycolipid-dependent human anaphylaxis; the delay mechanism in particular is
not captured,
so translational validity for the human effector phase is uncertain.
evidence:
- reference: PMID:38390396
reference_title: "Tick bite-induced alpha-gal syndrome and immunologic responses in an alpha-gal deficient murine model."
supports: PARTIAL
evidence_source: MODEL_ORGANISM
snippet: "significant increase in the total IgE, IgG1, and"
explanation: The model's alpha-gal-specific response is reported as IgG1 (with a
hypothermia readout), differing from the human IgE-mediated delayed anaphylaxis
it is meant to model.
proposed_experiments:
- name: Glycolipid-carrier delayed-effector challenge model
experiment_id: exp_ags_glycolipid_delay_model
description: >-
Test whether administering alpha-gal on glycolipid/chylomicron carriers
(versus glycoprotein) to tick-sensitized humanized-IgE effector systems
reproduces the characteristic multi-hour delay, to establish a model that
captures the delayed effector phase rather than only sensitization.
- discussion_id: disc_ags_cardiovascular_association
prompt: >-
Is alpha-gal sensitization causally linked to cardiovascular disease
(e.g. via IgE-mediated effects on atherosclerotic plaque), or is the reported
association confounded?
kind: EMERGING_HYPOTHESIS
status: OPEN
attaches_to:
- pathophysiology#Alpha-gal-specific IgE and effector-cell sensitization
rationale: >-
An emerging association between alpha-gal sensitization and cardiovascular
disease would extend AGS beyond acute allergy to a chronic vascular
comorbidity, but causality and mechanism are not yet established.
evidence:
- reference: PMID:38193233
reference_title: "Tick bites, IgE to galactose-alpha-1,3-galactose and urticarial or anaphylactic reactions to mammalian meat: The alpha-gal syndrome."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "alpha-gal sensitization has also been linked with cardiovascular
disease"
explanation: A recent authoritative review notes the emerging alpha-gal /
cardiovascular-disease association as a newly recognized dimension of AGS.
references:
- reference: PMID:18337601
title: Cetuximab-induced anaphylaxis and IgE specific for galactose-alpha-1,3-galactose.
findings: []
- reference: PMID:19070355
title: Delayed anaphylaxis, angioedema, or urticaria after consumption of red meat in patients with IgE antibodies specific for galactose-alpha-1,3-galactose.
findings: []
- reference: PMID:21453959
title: The relevance of tick bites to the production of IgE antibodies to the mammalian oligosaccharide galactose-α-1,3-galactose.
findings: []
- reference: PMID:19413526
title: An association between tick bite reactions and red meat allergy in humans.
findings: []
- reference: PMID:25747720
title: "The alpha-gal story: lessons learned from connecting the dots."
findings: []
- reference: PMID:38193233
title: "Tick bites, IgE to galactose-alpha-1,3-galactose and urticarial or anaphylactic reactions to mammalian meat: The alpha-gal syndrome."
findings: []
- reference: PMID:38390396
title: "Tick bite-induced alpha-gal syndrome and immunologic responses in an alpha-gal deficient murine model."
findings: []
- reference: PMID:30242261
title: "Tick galactosyltransferases are involved in α-Gal synthesis and play a role during Anaplasma phagocytophilum infection and Ixodes scapularis tick vector development."
findings: []
- reference: PMID:38741222
title: "Alpha-Gal, epitope responsible for allergy to red meat, in the Mediterranean tick Hyalomma lusitanicum."
findings: []
- reference: PMID:34034363
title: "Tick salivary gland extract induces alpha-gal syndrome in alpha-gal deficient mice."
findings: []
- reference: PMID:35382677
title: "Sensitisation and allergic reactions to alpha-1,3-galactose in Podlasie, Poland, an area endemic for tick-borne infections."
findings: []
- reference: PMID:31540167
title: "Tick Bites Induce Anti-α-Gal Antibodies in Dogs."
findings: []
- reference: PMID:39053323
title: "Identification of Alpha-Gal glycolipids in saliva of Lone-Star Tick (Amblyomma americanum)."
findings: []
- reference: PMID:40312115
title: "Alpha-gal syndrome: Recognizing and managing a tick-bite-related meat allergy."
findings: []
- reference: PMID:33009122
title: "'Doc, will I ever eat steak again?': diagnosis and management of alpha-gal syndrome."
findings: []
This report is retrieval-only and is generated directly from Asta results.
search_papers_by_relevance with snippet_search.Alpha-gal syndrome (AGS) is an IgE-mediated allergic disorder characterized by delayed hypersensitivity reactions to the oligosaccharide galactose-alpha-1,3-galactose (alpha-gal), a carbohydrate found in non-primate mammalian tissues, meat products, dairy, gelatin, and mammalian-derived medications (wilson2024tickbitesige pages 1-3, macdougall2022themeatof pages 1-2). Unlike conventional food allergies targeting proteins, AGS is uniquely directed against a carbohydrate epitope and features a characteristic delay of 2–6 hours between allergen ingestion and symptom onset (wilson2024tickbitesige pages 1-3, vazrodrigues2022currentandfuture pages 1-2). The syndrome was first recognized when patients experienced severe anaphylaxis upon infusion of cetuximab, a monoclonal antibody produced in mouse-derived cell lines, and subsequent investigation linked the sensitization to tick bites (propst2025alphagalsyndromeand pages 1-2). AGS is now recognized as the tenth most common food allergy in the United States, with an estimated 450,000 cases nationally (choudhary2025singlecellmrnaanalysis pages 1-2).
Information is derived primarily from aggregated disease-level resources (clinical reviews, cohort studies, case series) and clinical trial registrations, with single-cell profiling data from individual patient samples.
AGS is an acquired immunological disorder. The primary causal factor is sensitization to alpha-gal through bites of hard-bodied (ixodid) ticks, particularly Amblyomma americanum (lone star tick) in the southeastern United States (wilson2024tickbitesige pages 1-3, macdougall2022themeatof pages 2-4). Tick saliva contains alpha-gal residues on glycoproteins and glycolipids and other biomolecules such as prostaglandin E2, which, upon injection into the host during blood feeding, initiate an IgE-mediated immune response to alpha-gal (vazrodrigues2022currentandfuture pages 1-2). Tick saliva interferes with dendritic cell maturation, suppressing pro-inflammatory Th1/Th17 responses while promoting Th2 pro-allergic responses, which drives the production of alpha-gal-specific IgE by B cells (macdougall2022themeatof pages 2-4).
The alpha-gal carbohydrate is synthesized by the enzyme alpha-1,3-galactosyltransferase (encoded by the GGTA1 gene), which is functional in non-primate mammals but is a non-functional pseudogene in humans due to mutations accumulated over approximately 28 million years of evolution (cabezascruz2019environmentalandmolecular pages 1-2, wilson2024tickbitesige pages 3-4). This makes alpha-gal a foreign antigen highly immunogenic in humans (kepley2025tickedoffallergic pages 1-2).
Genetic/Intrinsic Risk Factors: - ABO blood type: Persons with blood type B are approximately one-fourth as likely to have AGS compared to blood type O, as the B-antigen is structurally similar to alpha-gal (sharing terminal galactoses connected by alpha-1,3 bonds) and may confer cross-protective immune tolerance (taylor2024intrinsicriskfactors pages 6-8, wilson2024tickbitesige pages 3-4). Individuals with A and O blood types have higher AGS risk (macdougall2022themeatof pages 4-5). - Race/ethnicity: White individuals showed higher seroconversion rates (6.6%) compared to Black (1.0%) and Hispanic (1.5%) populations in a military cohort, which may be partly attributable to differential distribution of protective B blood type alleles (taylor2024intrinsicriskfactors pages 6-8). - Atopy and childhood allergies: AGS case patients were significantly more likely to report childhood allergies that resolved in adulthood, family history of AGS (OR 8.33), family history of food allergies (OR 2.70), and vitamin D deficiency (taylor2024intrinsicriskfactors pages 1-3, taylor2024intrinsicriskfactors pages 5-6). - Heightened insect bite reactivity: Longer healing times for insect bites or stings (taylor2024intrinsicriskfactors pages 1-3). - Sex: Male sex has been identified as a risk factor for both sensitization and clinical AGS, though in case-control analyses, sex did not always reach significance when accounting for occupational exposure (macdougall2022themeatof pages 4-5).
Environmental Risk Factors: - Tick exposure: The predominant risk factor. 86% of diagnosed AGS patients report tick bite history (binder2023clinicalandlaboratory pages 1-1). Frequent tick exposure confers greater sensitization risk than single prolonged exposure (propst2025alphagalsyndromeand pages 1-2). - Outdoor occupation/activities: Forestry workers, rural workers, military personnel in outdoor occupations, hunters, and gardeners have elevated sensitization rates (nalcacı2024mysteriousallergycaused pages 6-7). Infantry/law enforcement personnel showed 12.7% seroconversion vs. 1.2% for administrative personnel (Ching et al. 2024). - Rural residence: Higher sensitization rates in rural versus urban areas (macdougall2022themeatof pages 4-5). - Cofactors: Alcohol consumption and exercise can potentiate allergic responses and lower the threshold for reactions (binder2023clinicalandlaboratory pages 2-2, propst2025alphagalsyndromeand pages 2-3).
The interplay between the non-functional human GGTA1 pseudogene (making alpha-gal foreign) and environmental tick bite exposure is the fundamental gene–environment interaction underlying AGS. Furthermore, intrinsic genetic factors influencing immune polarization (Th2 tendency, atopic constitution) interact with tick salivary components to determine whether an individual develops clinical AGS or remains asymptomatically sensitized (taylor2024intrinsicriskfactors pages 1-3, taylor2024intrinsicriskfactors pages 5-6).
The clinical presentation of AGS is diverse and often delayed, making diagnosis challenging. The following table summarizes major phenotypic features:
| Phenotype/Symptom | HPO Term | Frequency | Onset Timing | Severity | Notes |
|---|---|---|---|---|---|
| Urticaria / hives | HP:0001025 | Very common (about 60–80%) | Typically 2–6 hours after ingestion of mammalian meat/products | Mild to severe | Most common cutaneous manifestation; often part of delayed multisystem reactions in AGS (binder2023clinicalandlaboratory pages 2-2, vazrodrigues2022currentandfuture pages 1-2, binder2023clinicalandlaboratory pages 1-1) |
| Anaphylaxis | HP:0011844 | Common (up to about 60%) | Usually delayed 2–6 hours after exposure | Severe / life-threatening | Can involve ≥2 organ systems; 75% of patients in one US cohort met anaphylaxis criteria (vazrodrigues2022currentandfuture pages 1-2, binder2023clinicalandlaboratory pages 2-2, binder2023clinicalandlaboratory pages 1-1) |
| Angioedema | HP:0100665 | Common | Typically 2–6 hours after ingestion | Moderate to severe | Frequently accompanies urticaria and may occur with broader systemic reactions (binder2023clinicalandlaboratory pages 2-2, vazrodrigues2022currentandfuture pages 1-2) |
| Gastrointestinal symptoms (abdominal pain, nausea, vomiting, diarrhea) | HP:0002027, HP:0002018, HP:0002013, HP:0002014 | Common (about 59–79%) | Typically 2–6 hours after ingestion | Mild to severe | Can present in isolation without skin findings; often overlaps with IBS-like symptoms and may be under-recognized (binder2023clinicalandlaboratory pages 2-2, propst2025alphagalsyndromeand pages 1-2, macdougall2022themeatof pages 10-11) |
| Pruritus | HP:0000989 | Very common | Typically 2–6 hours after ingestion | Mild to moderate | Common early allergic manifestation; often accompanies hives or angioedema (vazrodrigues2022currentandfuture pages 1-2, nalcacı2024mysteriousallergycaused pages 1-2) |
| Cardiovascular symptoms | HP:0001626 | Uncommon | Variable; may occur during systemic reactions or in association studies | Potentially severe | Reported associations include noncalcified plaque, obstructive coronary artery disease, and STEMI; evidence includes sensitization/cardiovascular links beyond classic food reactions (wilson2024tickbitesige pages 1-3, propst2025alphagalsyndromeand pages 7-8) |
| Hypotension / shock | HP:0002615 | Uncommon | During anaphylaxis | Severe | Represents severe systemic involvement and requires prompt epinephrine-based management (vazrodrigues2022currentandfuture pages 6-7, leder2024perioperativeconsiderationsin pages 3-5) |
| Respiratory distress | HP:0002098 | Less common | During anaphylaxis | Severe | Part of the anaphylactic cascade; more concerning in severe systemic AGS reactions (vazrodrigues2022currentandfuture pages 6-7, NCT06268717 chunk 2, NCT07611435 chunk 1) |
Table: This table summarizes the major clinical phenotypes of Alpha-gal Syndrome, including suggested HPO terms, approximate frequencies, timing, severity, and clinically useful notes. It is useful for structuring phenotype annotations in a disease knowledge base.
AGS is not a Mendelian genetic disease but rather an acquired immunological condition. However, the evolutionary loss of GGTA1 function in humans is the molecular prerequisite. The GGTA1 gene encodes alpha-1,3-galactosyltransferase (HGNC:4319), the enzyme responsible for synthesizing the alpha-gal epitope on glycoproteins and glycolipids. In humans and Old World primates, GGTA1 is a pseudogene that produces only truncated transcripts lacking the two catalytic exons needed for enzyme activity (cabezascruz2019environmentalandmolecular pages 1-2). At least two separate mutations account for this loss of function, accumulated over ~28 million years (wilson2024tickbitesige pages 3-4). Non-primate mammals, New World monkeys, and platyrrhine primates retain a functional GGTA1 gene (carson2022where’sthebeef? pages 1-3).
Single-cell analysis has revealed that alpha-gal-specific IgE is secreted by a heterogeneous population of B cells, including CCR6-proficient memory B cells and CCR6-deficient plasmablasts/plasma cells. Individual B cells were found to express IgE-secreting transcripts alongside other immunoglobulin classes (IgA, IgG, IgM), suggesting a unique pattern of Ig gene arrangements and class switching (choudhary2025singlecellmrnaanalysis pages 1-2, choudhary2025singlecellmrnaanalysis pages 14-17).
AGS does not involve pathogenic variants in the traditional clinical genetics sense. The disease is acquired through environmental exposure (tick bites), and susceptibility is modulated by ABO blood group genotype and atopic predisposition rather than by mutations in a single causative gene.
Tick bites are the sensitizing event. The following table summarizes tick species associated with AGS worldwide:
| Tick Species | Geographic Region/Country | Reference |
|---|---|---|
| Amblyomma americanum | Southeastern United States; Coastal Atlantic states, USA | (wilson2024tickbitesige pages 3-4, sharma2024tickbiteinducedalphagal pages 1-2, platts‐mills2025theimmunologyof pages 6-8) |
| Ixodes holocyclus | Australia; especially eastern coastal Australia | (wilson2024tickbitesige pages 3-4, sharma2024tickbiteinducedalphagal pages 1-2, platts‐mills2025theimmunologyof pages 6-8) |
| Ixodes ricinus | Europe (including Sweden, Germany, broader established range) | (vazrodrigues2022currentandfuture pages 1-2, wilson2024tickbitesige pages 3-4, sharma2024tickbiteinducedalphagal pages 1-2, choudhary2025singlecellmrnaanalysis pages 1-2) |
| Haemaphysalis longicornis | Japan/Asia | (vazrodrigues2022currentandfuture pages 1-2, sharma2024tickbiteinducedalphagal pages 1-2, choudhary2025singlecellmrnaanalysis pages 1-2, platts‐mills2025theimmunologyof pages 6-8) |
| Amblyomma sculptum | Brazil | (sharma2024tickbiteinducedalphagal pages 1-2, choudhary2025singlecellmrnaanalysis pages 1-2) |
| Rhipicephalus bursa | Europe | (sharma2024tickbiteinducedalphagal pages 1-2) |
| Hyalomma marginatum | Europe | (sharma2024tickbiteinducedalphagal pages 1-2) |
| Ixodes scapularis | Eastern United States | (sharma2024tickbiteinducedalphagal pages 1-2, platts‐mills2025theimmunologyof pages 6-8) |
| Amblyomma testudinarium | Asia | (platts‐mills2025theimmunologyof pages 6-8) |
| Ixodes pacificus | Western United States | (platts‐mills2025theimmunologyof pages 6-8) |
Table: This table summarizes tick species reported in the literature as implicated in alpha-gal sensitization or alpha-gal syndrome across major world regions. It is useful for mapping geographic risk and understanding regional differences in AGS epidemiology.
The causal chain begins with tick attachment and blood feeding. Tick saliva contains alpha-gal on glycoproteins and glycolipids, along with immunomodulatory molecules including prostaglandin E2 (vazrodrigues2022currentandfuture pages 1-2). Tick saliva interferes with dendritic cell maturation, suppressing Th1/Th17 responses while favoring Th2 pro-allergic polarization (macdougall2022themeatof pages 2-4). Antigen-presenting cells (dendritic cells, macrophages, B cells) present alpha-gal to Th2 cells, which produce IL-4 and IL-13, driving B cell class switching to IgE (vazrodrigues2022currentandfuture pages 1-2). Repeated tick bites strengthen the Th2 signal (platts‐mills2025theimmunologyof pages 11-13). Notably, all humans produce natural IgG, IgM, and IgA antibodies to alpha-gal from gastrointestinal bacterial exposure, but IgE production is the pathological consequence of tick-mediated sensitization (wilson2024tickbitesige pages 1-3, carson2022where’sthebeef? pages 3-4).
Upon consumption of mammalian meat, alpha-gal glycolipids cross the intestinal epithelial barrier and are incorporated into chylomicrons in lacteals, entering systemic circulation approximately one hour post-ingestion (platts‐mills2025theimmunologyof pages 11-13). Over 2–6 hours, chylomicrons (300–1000 nm) are progressively metabolized to VLDL and LDL particles (12–25 nm), which carry alpha-gal on their surface glycosylation (platts‐mills2025theimmunologyof pages 11-13). These smaller LDL particles can extravasate through endothelial walls into tissue compartments where they encounter mast cells bearing alpha-gal-specific IgE on FcεRI receptors. Alpha-gal on LDL cross-links surface-bound IgE, triggering mast cell and basophil degranulation and release of histamine, leukotrienes, and tryptase (platts‐mills2025theimmunologyof pages 11-13, branicka2025alphagalsyndrome—aseries pages 4-6). Basophil activation peaks approximately 4 hours after meat consumption, correlating with clinical symptom appearance (macdougall2022themeatof pages 2-4, carson2022where’sthebeef? pages 9-11). AGS patients also show significant differences in lipid metabolism, with delayed lipid processing contributing to the prolonged interval between ingestion and reaction (carson2022where’sthebeef? pages 8-9, kepley2025tickedoffallergic pages 7-8).
Alpha-gal sensitization has been associated with noncalcified plaque, obstructive coronary artery disease, and ST-segment-elevated myocardial infarction (propst2025alphagalsyndromeand pages 7-8). Chronic IgE-mediated inflammation from bioprosthetic valve implantation (containing alpha-gal) may contribute to early valve degradation and accelerated coronary artery disease (kuravi2022allergicresponseto pages 1-2, kuravi2022allergicresponseto pages 6-9).
Single-cell analysis (Choudhary & Commins, 2025): Multimodal single-cell RNA transcriptome and surface protein analysis of PBMCs from 18 AGS and 10 control subjects captured 437,770 total cells and identified 43 distinct immune cell clusters (choudhary2025singlecellmrnaanalysis pages 4-5). Key findings include: - Circulating mast cell progenitors (cluster C43) with 53-fold elevated TPSAB1/tryptase and 8-fold elevated KIT expression (choudhary2025singlecellmrnaanalysis pages 8-11) - CD4+-NKT cells predominantly from AGS subjects (96% in cluster C32) linked to Th2 responses (choudhary2025singlecellmrnaanalysis pages 17-18) - 1,141 IgE-secreting cells containing 11,017 IgE transcripts identified (choudhary2025singlecellmrnaanalysis pages 14-17) - Elevated S100A9, IFITM3, and THBS1 across multiple cell types in AGS subjects (choudhary2025singlecellmrnaanalysis pages 17-18) - Enhanced antigen presentation genes: CD52, CXCL16, HLA-DPA1, HLA-DRA, ICAM1, IFITM3, LAP3, THBS1 (choudhary2025singlecellmrnaanalysis pages 8-11)
AGS is not inherited in a Mendelian fashion. It is an acquired immunological condition. However, familial clustering has been observed—AGS patients are 8.33 times more likely to report relatives with AGS (taylor2024intrinsicriskfactors pages 5-6)—which may reflect shared genetic predisposition (atopy, blood type), shared environmental exposures (tick habitat), and increased diagnostic awareness within families.
Diagnosis is based on: (1) compatible clinical history of delayed allergic reactions to mammalian meat/products, (2) elevated alpha-gal-specific IgE, and (3) exclusion of alternative diagnoses. No universally standardized diagnostic criteria exist (binder2023clinicalandlaboratory pages 2-3).
AGS can be life-threatening when anaphylaxis occurs, but mortality data are limited. The primary morbidity includes recurrent allergic reactions, dietary restriction, quality of life impairment, and diagnostic delay (macdougall2022themeatof pages 11-13). AGS is a leading cause of anaphylaxis in southeastern US adults and adolescents (macdougall2022themeatof pages 4-5).
Patients with AGS require careful perioperative medication review. Many common anesthetic and surgical products contain mammalian-derived alpha-gal, including heparin, gelatin-based hemostatic agents (surgifoam), gelatin capsules, propofol (glycerol content), and bioprosthetic heart valves (leder2024perioperativeconsiderationsin pages 3-5, leder2024perioperativeconsiderationsin pages 2-3, leder2024perioperativeconsiderationsin pages 1-2). Preoperative steroids and antihistamines are recommended before high-dose heparin exposure, and alternative anticoagulants (sodium citrate) should be considered (commins2020diagnosis&management pages 16-18, leder2024perioperativeconsiderationsin pages 2-3). 24–50% of AGS patients undergoing cardiac surgery with cardiopulmonary bypass experienced severe allergic reactions (leder2024perioperativeconsiderationsin pages 2-3). Intravenous formulations are generally safer than oral formulations due to fewer mammalian-derived fillers (leder2024perioperativeconsiderationsin pages 7-9).
The following table summarizes active and completed clinical trials for AGS:
| NCT ID | Title | Phase | Status | Sponsor | Enrollment | Key Design Features |
|---|---|---|---|---|---|---|
| NCT06268717 | GI Alpha-Gal Study | NA | Completed | University of North Carolina, Chapel Hill | 30 | Double-blind randomized crossover food challenge comparing pork with alpha-gal vs pork without alpha-gal; includes lactulose/C13 mannitol testing, transnasal upper endoscopy with GI biopsies, basophil activation, tryptase, and mRNA/pathology studies (NCT06268717 chunk 1, NCT06268717 chunk 2) |
| NCT04828317 | Alpha-gal Pork Challenge | NA | Unknown | University of Virginia | 54 | Pork challenge study in alpha-gal syndrome; interventional design evaluating clinical responses to pork exposure (clinical trial search result in prior tool output) |
| NCT07611435 | Beginning to Assess an Appropriate CONtrol for Oral Food Challenges in Alpha-Gal Syndrome (CoFAR-13) - BeACON4AG | Phase 2 | Not yet recruiting | National Institute of Allergy and Infectious Diseases (NIAID) | 160 | Multisite randomized double-blind crossover diagnostic trial; participants receive alpha-gal knockout pork and wild-type pork on separate visits to compare odds of positive double-blind food challenges and define AGS sub-phenotypes (NCT07611435 chunk 1, NCT07611435 chunk 2) |
| NCT07177729 | The α-gal Syndrome - Investigating Immune Reactions to Tick Bites (ImmunoGal) | Observational | Recruiting | Luxembourg Institute of Health | 100 | Prospective cohort enrolling participants within 48 hours of tick removal; longitudinal blood sampling, tick collection/PCR, serology, and multi-omics immune profiling to identify signatures associated with alpha-gal sensitization after tick bites (NCT07177729 chunk 1) |
| NCT07526558 | Mast Cell Treatment in Post-tick Bite Illness (PTBI) | Phase 2 | Not yet recruiting | University of North Carolina, Chapel Hill | 50 | Randomized double-blind parallel pilot trial testing ketotifen + cromolyn + fexofenadine versus fexofenadine alone for persistent mast cell activation symptoms after post-tick bite illness, including AGS (NCT07526558 chunk 1) |
Table: This table summarizes the main clinical trials identified for alpha-gal syndrome and related post-tick bite illness. It is useful for quickly comparing study design, status, enrollment, and the main research focus of each trial.
Alpha-gal is widely expressed in non-primate mammals (including cows, pigs, sheep, deer), bacteria, and parasites including ticks (wilson2024tickbitesige pages 1-3). The alpha-gal epitope is synthesized by functional alpha-1,3-galactosyltransferase in these organisms. Tick galactosyltransferases are involved in synthesizing alpha-gal in tick tissues and saliva (cabezascruz2019environmentalandmolecular pages 1-2). N-glycome profiling and proteome analysis have demonstrated alpha-gal antigens in salivary gland extracts and saliva of A. americanum and Ixodes scapularis, but not in Amblyomma maculatum (sharma2024tickbiteinducedalphagal pages 1-2).
AGS is fundamentally a vector-borne allergic disease. The sensitization pathway is unique in that it involves an arthropod vector (tick) but is not an infectious disease. The clinical syndrome is dependent on subsequent exposure to mammalian-derived products, making it a complex interface of ectoparasite biology and human immunology.
The primary animal model is the alpha-gal knockout (AGKO) mouse, which has a targeted disruption of alpha-1,3-galactosyltransferase and therefore cannot produce alpha-gal, mimicking the human condition (sharma2024tickbiteinducedalphagal pages 1-2). In this model: - A. americanum nymph infestation induced significant increases in total IgE, IgG1, and alpha-gal IgG1 antibody titers compared to A. maculatum-sensitized mice (sharma2024tickbiteinducedalphagal pages 1-2). - Pork challenge in A. americanum-sensitized AGKO mice led to body temperature decline (anaphylaxis-like response) (sharma2024tickbiteinducedalphagal pages 1-2). - Gene expression analysis revealed A. americanum bites direct mouse immunity toward Th2 polarization (sharma2024tickbiteinducedalphagal pages 1-2).
This report draws from 17 primary research publications and 4 clinical trial registrations, including comprehensive reviews in Allergy (Wilson et al. 2024), Journal of Immunology (Carson et al. 2022), ImmunoTargets and Therapy (Macdougall et al. 2022), Immunological Reviews (Platts-Mills et al. 2025), Frontiers in Immunology (Sharma et al. 2024; Choudhary & Commins 2025), and clinical data from the CDC-affiliated cohort study published in Allergy (Binder et al. 2023) and the case-control study in Annals of Allergy, Asthma & Immunology (Taylor et al. 2024).
References
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(vazrodrigues2022currentandfuture pages 1-2): Rita Vaz-Rodrigues, Lorena Mazuecos, and José de la Fuente. Current and future strategies for the diagnosis and treatment of the alpha-gal syndrome (ags). Journal of Asthma and Allergy, 15:957-970, Jul 2022. URL: https://doi.org/10.2147/jaa.s265660, doi:10.2147/jaa.s265660. This article has 70 citations and is from a peer-reviewed journal.
(propst2025alphagalsyndromeand pages 1-2): Susan B. H. Propst and Dorothea K. Thompson. Alpha-gal syndrome and the gastrointestinal reaction: a narrative review. Frontiers in Allergy, Jan 2025. URL: https://doi.org/10.3389/falgy.2025.1535103, doi:10.3389/falgy.2025.1535103. This article has 13 citations and is from a peer-reviewed journal.
(choudhary2025singlecellmrnaanalysis pages 1-2): Shailesh K. Choudhary and Scott P. Commins. Single-cell mrna analysis and surface marker expression profiling of circulating immune cells in humans with alpha-gal syndrome. Frontiers in Immunology, Sep 2025. URL: https://doi.org/10.3389/fimmu.2025.1629310, doi:10.3389/fimmu.2025.1629310. This article has 2 citations and is from a peer-reviewed journal.
(NCT06268717 chunk 2): GI Alpha-Gal Study. University of North Carolina, Chapel Hill. 2023. ClinicalTrials.gov Identifier: NCT06268717
(wilson2024tickbitesige pages 3-4): Jeffrey M. Wilson, Loren Erickson, Michael Levin, Samuel M. Ailsworth, Scott P. Commins, and Thomas A. E. Platts‐Mills. Tick bites, ige to galactose-alpha-1,3-galactose and urticarial or anaphylactic reactions to mammalian meat: the alpha-gal syndrome. Allergy, 79:1440-1454, Jan 2024. URL: https://doi.org/10.1111/all.16003, doi:10.1111/all.16003. This article has 72 citations and is from a highest quality peer-reviewed journal.
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(taylor2024intrinsicriskfactors pages 6-8): Marissa L. Taylor, Gilbert J. Kersh, Johanna S. Salzer, Emma S. Jones, Alison M. Binder, Paige A. Armstrong, Shailesh K. Choudhary, Grace K. Commins, Claire L. Amelio, Brad J. Biggerstaff, Charles B. Beard, Lyle R. Petersen, and Scott P. Commins. Intrinsic risk factors for alpha-gal syndrome in a case-control study, 2019 to 2020. Annals of Allergy, Asthma & Immunology, 132:759-764.e2, Jun 2024. URL: https://doi.org/10.1016/j.anai.2024.01.029, doi:10.1016/j.anai.2024.01.029. This article has 23 citations.
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(taylor2024intrinsicriskfactors pages 1-3): Marissa L. Taylor, Gilbert J. Kersh, Johanna S. Salzer, Emma S. Jones, Alison M. Binder, Paige A. Armstrong, Shailesh K. Choudhary, Grace K. Commins, Claire L. Amelio, Brad J. Biggerstaff, Charles B. Beard, Lyle R. Petersen, and Scott P. Commins. Intrinsic risk factors for alpha-gal syndrome in a case-control study, 2019 to 2020. Annals of Allergy, Asthma & Immunology, 132:759-764.e2, Jun 2024. URL: https://doi.org/10.1016/j.anai.2024.01.029, doi:10.1016/j.anai.2024.01.029. This article has 23 citations.
(taylor2024intrinsicriskfactors pages 5-6): Marissa L. Taylor, Gilbert J. Kersh, Johanna S. Salzer, Emma S. Jones, Alison M. Binder, Paige A. Armstrong, Shailesh K. Choudhary, Grace K. Commins, Claire L. Amelio, Brad J. Biggerstaff, Charles B. Beard, Lyle R. Petersen, and Scott P. Commins. Intrinsic risk factors for alpha-gal syndrome in a case-control study, 2019 to 2020. Annals of Allergy, Asthma & Immunology, 132:759-764.e2, Jun 2024. URL: https://doi.org/10.1016/j.anai.2024.01.029, doi:10.1016/j.anai.2024.01.029. This article has 23 citations.
(binder2023clinicalandlaboratory pages 1-1): Alison M. Binder, Dena Cherry‐Brown, Brad J. Biggerstaff, Emma S. Jones, Claire L. Amelio, Charles B. Beard, Lyle R. Petersen, Gilbert J. Kersh, Scott P. Commins, and Paige A. Armstrong. Clinical and laboratory features of patients diagnosed with alpha‐gal syndrome—2010–2019. Allergy, 78:477-487, Oct 2023. URL: https://doi.org/10.1111/all.15539, doi:10.1111/all.15539. This article has 42 citations and is from a highest quality peer-reviewed journal.
(nalcacı2024mysteriousallergycaused pages 6-7): Muhammed Nalçacı. Mysterious allergy caused by tick bite: alpha-gal syndrome. Turkiye parazitolojii dergisi, 48 3:195-207, Oct 2024. URL: https://doi.org/10.4274/tpd.galenos.2024.97720, doi:10.4274/tpd.galenos.2024.97720. This article has 7 citations.
(binder2023clinicalandlaboratory pages 2-2): Alison M. Binder, Dena Cherry‐Brown, Brad J. Biggerstaff, Emma S. Jones, Claire L. Amelio, Charles B. Beard, Lyle R. Petersen, Gilbert J. Kersh, Scott P. Commins, and Paige A. Armstrong. Clinical and laboratory features of patients diagnosed with alpha‐gal syndrome—2010–2019. Allergy, 78:477-487, Oct 2023. URL: https://doi.org/10.1111/all.15539, doi:10.1111/all.15539. This article has 42 citations and is from a highest quality peer-reviewed journal.
(propst2025alphagalsyndromeand pages 2-3): Susan B. H. Propst and Dorothea K. Thompson. Alpha-gal syndrome and the gastrointestinal reaction: a narrative review. Frontiers in Allergy, Jan 2025. URL: https://doi.org/10.3389/falgy.2025.1535103, doi:10.3389/falgy.2025.1535103. This article has 13 citations and is from a peer-reviewed journal.
(carson2022where’sthebeef? pages 3-4): Audrey S. Carson, Aliyah Gardner, and Onyinye I. Iweala. Where’s the beef? : understanding allergic responses to red meat in alpha-gal syndrome. Journal of immunology (Baltimore, Md. : 1950), 208:267-277, Jan 2022. URL: https://doi.org/10.4049/jimmunol.2100712, doi:10.4049/jimmunol.2100712. This article has 47 citations.
(vazrodrigues2022currentandfuture pages 6-7): Rita Vaz-Rodrigues, Lorena Mazuecos, and José de la Fuente. Current and future strategies for the diagnosis and treatment of the alpha-gal syndrome (ags). Journal of Asthma and Allergy, 15:957-970, Jul 2022. URL: https://doi.org/10.2147/jaa.s265660, doi:10.2147/jaa.s265660. This article has 70 citations and is from a peer-reviewed journal.
(macdougall2022themeatof pages 10-11): Jessica D Macdougall, Kevin O Thomas, and Onyinye I Iweala. The meat of the matter: understanding and managing alpha-gal syndrome. ImmunoTargets and Therapy, 11:37-54, Sep 2022. URL: https://doi.org/10.2147/itt.s276872, doi:10.2147/itt.s276872. This article has 71 citations.
(nalcacı2024mysteriousallergycaused pages 1-2): Muhammed Nalçacı. Mysterious allergy caused by tick bite: alpha-gal syndrome. Turkiye parazitolojii dergisi, 48 3:195-207, Oct 2024. URL: https://doi.org/10.4274/tpd.galenos.2024.97720, doi:10.4274/tpd.galenos.2024.97720. This article has 7 citations.
(propst2025alphagalsyndromeand pages 7-8): Susan B. H. Propst and Dorothea K. Thompson. Alpha-gal syndrome and the gastrointestinal reaction: a narrative review. Frontiers in Allergy, Jan 2025. URL: https://doi.org/10.3389/falgy.2025.1535103, doi:10.3389/falgy.2025.1535103. This article has 13 citations and is from a peer-reviewed journal.
(leder2024perioperativeconsiderationsin pages 3-5): John Leder, Anna Diederich, Bhavik Patel, Mark Bowie, Christian M Renwick, and Venkat Mangunta. Perioperative considerations in alpha-gal syndrome: a review. Cureus, Jan 2024. URL: https://doi.org/10.7759/cureus.53208, doi:10.7759/cureus.53208. This article has 16 citations.
(NCT07611435 chunk 1): Beginning to Assess an Appropriate CONtrol for Oral Food Challenges in Alpha-Gal Syndrome (CoFAR-13) - BeACON4AG. National Institute of Allergy and Infectious Diseases (NIAID). 2026. ClinicalTrials.gov Identifier: NCT07611435
(macdougall2022themeatof pages 11-13): Jessica D Macdougall, Kevin O Thomas, and Onyinye I Iweala. The meat of the matter: understanding and managing alpha-gal syndrome. ImmunoTargets and Therapy, 11:37-54, Sep 2022. URL: https://doi.org/10.2147/itt.s276872, doi:10.2147/itt.s276872. This article has 71 citations.
(carson2022where’sthebeef? pages 1-3): Audrey S. Carson, Aliyah Gardner, and Onyinye I. Iweala. Where’s the beef? : understanding allergic responses to red meat in alpha-gal syndrome. Journal of immunology (Baltimore, Md. : 1950), 208:267-277, Jan 2022. URL: https://doi.org/10.4049/jimmunol.2100712, doi:10.4049/jimmunol.2100712. This article has 47 citations.
(choudhary2025singlecellmrnaanalysis pages 14-17): Shailesh K. Choudhary and Scott P. Commins. Single-cell mrna analysis and surface marker expression profiling of circulating immune cells in humans with alpha-gal syndrome. Frontiers in Immunology, Sep 2025. URL: https://doi.org/10.3389/fimmu.2025.1629310, doi:10.3389/fimmu.2025.1629310. This article has 2 citations and is from a peer-reviewed journal.
(commins2020diagnosis&management pages 16-18): Scott P. Commins. Diagnosis & management of alpha-gal syndrome: lessons from 2,500 patients. Jul 2020. URL: https://doi.org/10.1080/1744666x.2020.1782745, doi:10.1080/1744666x.2020.1782745. This article has 114 citations and is from a peer-reviewed journal.
(sharma2024tickbiteinducedalphagal pages 1-2): Surendra Raj Sharma, Shailesh K. Choudhary, Julia Vorobiov, Scott P. Commins, and Shahid Karim. Tick bite-induced alpha-gal syndrome and immunologic responses in an alpha-gal deficient murine model. Frontiers in Immunology, Feb 2024. URL: https://doi.org/10.3389/fimmu.2023.1336883, doi:10.3389/fimmu.2023.1336883. This article has 28 citations and is from a peer-reviewed journal.
(platts‐mills2025theimmunologyof pages 6-8): Thomas A. E. Platts‐Mills, Roopesh Singh Gangwar, Lisa Workman, and Jeffrey M. Wilson. The immunology of alpha‐gal syndrome: history, tick bites, ige, and delayed anaphylaxis to mammalian meat. Immunological Reviews, Jun 2025. URL: https://doi.org/10.1111/imr.70035, doi:10.1111/imr.70035. This article has 19 citations and is from a domain leading peer-reviewed journal.
(platts‐mills2025theimmunologyof pages 11-13): Thomas A. E. Platts‐Mills, Roopesh Singh Gangwar, Lisa Workman, and Jeffrey M. Wilson. The immunology of alpha‐gal syndrome: history, tick bites, ige, and delayed anaphylaxis to mammalian meat. Immunological Reviews, Jun 2025. URL: https://doi.org/10.1111/imr.70035, doi:10.1111/imr.70035. This article has 19 citations and is from a domain leading peer-reviewed journal.
(branicka2025alphagalsyndrome—aseries pages 4-6): Olga Branicka, Lesia Rozłucka, Radosław Gawlik, and Joanna Glück. Alpha-gal syndrome—a series of cases with different clinical pictures. International Journal of Molecular Sciences, 26:8601, Sep 2025. URL: https://doi.org/10.3390/ijms26178601, doi:10.3390/ijms26178601. This article has 0 citations.
(carson2022where’sthebeef? pages 9-11): Audrey S. Carson, Aliyah Gardner, and Onyinye I. Iweala. Where’s the beef? : understanding allergic responses to red meat in alpha-gal syndrome. Journal of immunology (Baltimore, Md. : 1950), 208:267-277, Jan 2022. URL: https://doi.org/10.4049/jimmunol.2100712, doi:10.4049/jimmunol.2100712. This article has 47 citations.
(carson2022where’sthebeef? pages 8-9): Audrey S. Carson, Aliyah Gardner, and Onyinye I. Iweala. Where’s the beef? : understanding allergic responses to red meat in alpha-gal syndrome. Journal of immunology (Baltimore, Md. : 1950), 208:267-277, Jan 2022. URL: https://doi.org/10.4049/jimmunol.2100712, doi:10.4049/jimmunol.2100712. This article has 47 citations.
(kepley2025tickedoffallergic pages 7-8): Christopher L. Kepley, Yinghui Wang, Amy Yelton, Eva R. Siebert, and Onyinye I. Iweala. Ticked off: allergic effector cells in the pathogenesis of alpha-gal syndrome. Current Allergy and Asthma Reports, Nov 2025. URL: https://doi.org/10.1007/s11882-025-01237-2, doi:10.1007/s11882-025-01237-2. This article has 3 citations and is from a peer-reviewed journal.
(carson2022where’sthebeef? pages 6-8): Audrey S. Carson, Aliyah Gardner, and Onyinye I. Iweala. Where’s the beef? : understanding allergic responses to red meat in alpha-gal syndrome. Journal of immunology (Baltimore, Md. : 1950), 208:267-277, Jan 2022. URL: https://doi.org/10.4049/jimmunol.2100712, doi:10.4049/jimmunol.2100712. This article has 47 citations.
(choudhary2025singlecellmrnaanalysis pages 17-18): Shailesh K. Choudhary and Scott P. Commins. Single-cell mrna analysis and surface marker expression profiling of circulating immune cells in humans with alpha-gal syndrome. Frontiers in Immunology, Sep 2025. URL: https://doi.org/10.3389/fimmu.2025.1629310, doi:10.3389/fimmu.2025.1629310. This article has 2 citations and is from a peer-reviewed journal.
(kuravi2022allergicresponseto pages 1-2): Kasinath V. Kuravi, Lori T. Sorrells, Joseph R. Nellis, Farzana Rahman, Anneke H. Walters, Robert G. Matheny, Shailesh K. Choudhary, David L. Ayares, Scott P. Commins, John R. Bianchi, and Joseph W. Turek. Allergic response to medical products in patients with alpha-gal syndrome. The Journal of Thoracic and Cardiovascular Surgery, 164:e411-e424, Dec 2022. URL: https://doi.org/10.1016/j.jtcvs.2021.03.100, doi:10.1016/j.jtcvs.2021.03.100. This article has 72 citations.
(kuravi2022allergicresponseto pages 6-9): Kasinath V. Kuravi, Lori T. Sorrells, Joseph R. Nellis, Farzana Rahman, Anneke H. Walters, Robert G. Matheny, Shailesh K. Choudhary, David L. Ayares, Scott P. Commins, John R. Bianchi, and Joseph W. Turek. Allergic response to medical products in patients with alpha-gal syndrome. The Journal of Thoracic and Cardiovascular Surgery, 164:e411-e424, Dec 2022. URL: https://doi.org/10.1016/j.jtcvs.2021.03.100, doi:10.1016/j.jtcvs.2021.03.100. This article has 72 citations.
(choudhary2025singlecellmrnaanalysis pages 4-5): Shailesh K. Choudhary and Scott P. Commins. Single-cell mrna analysis and surface marker expression profiling of circulating immune cells in humans with alpha-gal syndrome. Frontiers in Immunology, Sep 2025. URL: https://doi.org/10.3389/fimmu.2025.1629310, doi:10.3389/fimmu.2025.1629310. This article has 2 citations and is from a peer-reviewed journal.
(choudhary2025singlecellmrnaanalysis pages 8-11): Shailesh K. Choudhary and Scott P. Commins. Single-cell mrna analysis and surface marker expression profiling of circulating immune cells in humans with alpha-gal syndrome. Frontiers in Immunology, Sep 2025. URL: https://doi.org/10.3389/fimmu.2025.1629310, doi:10.3389/fimmu.2025.1629310. This article has 2 citations and is from a peer-reviewed journal.
(binder2023clinicalandlaboratory pages 8-8): Alison M. Binder, Dena Cherry‐Brown, Brad J. Biggerstaff, Emma S. Jones, Claire L. Amelio, Charles B. Beard, Lyle R. Petersen, Gilbert J. Kersh, Scott P. Commins, and Paige A. Armstrong. Clinical and laboratory features of patients diagnosed with alpha‐gal syndrome—2010–2019. Allergy, 78:477-487, Oct 2023. URL: https://doi.org/10.1111/all.15539, doi:10.1111/all.15539. This article has 42 citations and is from a highest quality peer-reviewed journal.
(binder2023clinicalandlaboratory pages 2-3): Alison M. Binder, Dena Cherry‐Brown, Brad J. Biggerstaff, Emma S. Jones, Claire L. Amelio, Charles B. Beard, Lyle R. Petersen, Gilbert J. Kersh, Scott P. Commins, and Paige A. Armstrong. Clinical and laboratory features of patients diagnosed with alpha‐gal syndrome—2010–2019. Allergy, 78:477-487, Oct 2023. URL: https://doi.org/10.1111/all.15539, doi:10.1111/all.15539. This article has 42 citations and is from a highest quality peer-reviewed journal.
(NCT06268717 chunk 1): GI Alpha-Gal Study. University of North Carolina, Chapel Hill. 2023. ClinicalTrials.gov Identifier: NCT06268717
(macdougall2022themeatof pages 7-8): Jessica D Macdougall, Kevin O Thomas, and Onyinye I Iweala. The meat of the matter: understanding and managing alpha-gal syndrome. ImmunoTargets and Therapy, 11:37-54, Sep 2022. URL: https://doi.org/10.2147/itt.s276872, doi:10.2147/itt.s276872. This article has 71 citations.
(macdougall2022themeatof pages 8-10): Jessica D Macdougall, Kevin O Thomas, and Onyinye I Iweala. The meat of the matter: understanding and managing alpha-gal syndrome. ImmunoTargets and Therapy, 11:37-54, Sep 2022. URL: https://doi.org/10.2147/itt.s276872, doi:10.2147/itt.s276872. This article has 71 citations.
(propst2025alphagalsyndromeand pages 4-5): Susan B. H. Propst and Dorothea K. Thompson. Alpha-gal syndrome and the gastrointestinal reaction: a narrative review. Frontiers in Allergy, Jan 2025. URL: https://doi.org/10.3389/falgy.2025.1535103, doi:10.3389/falgy.2025.1535103. This article has 13 citations and is from a peer-reviewed journal.
(vazrodrigues2022currentandfuture pages 7-8): Rita Vaz-Rodrigues, Lorena Mazuecos, and José de la Fuente. Current and future strategies for the diagnosis and treatment of the alpha-gal syndrome (ags). Journal of Asthma and Allergy, 15:957-970, Jul 2022. URL: https://doi.org/10.2147/jaa.s265660, doi:10.2147/jaa.s265660. This article has 70 citations and is from a peer-reviewed journal.
(NCT07526558 chunk 1): Mast Cell Treatment in Post-tick Bite Illness (PTBI). University of North Carolina, Chapel Hill. 2026. ClinicalTrials.gov Identifier: NCT07526558
(leder2024perioperativeconsiderationsin pages 2-3): John Leder, Anna Diederich, Bhavik Patel, Mark Bowie, Christian M Renwick, and Venkat Mangunta. Perioperative considerations in alpha-gal syndrome: a review. Cureus, Jan 2024. URL: https://doi.org/10.7759/cureus.53208, doi:10.7759/cureus.53208. This article has 16 citations.
(leder2024perioperativeconsiderationsin pages 1-2): John Leder, Anna Diederich, Bhavik Patel, Mark Bowie, Christian M Renwick, and Venkat Mangunta. Perioperative considerations in alpha-gal syndrome: a review. Cureus, Jan 2024. URL: https://doi.org/10.7759/cureus.53208, doi:10.7759/cureus.53208. This article has 16 citations.
(leder2024perioperativeconsiderationsin pages 7-9): John Leder, Anna Diederich, Bhavik Patel, Mark Bowie, Christian M Renwick, and Venkat Mangunta. Perioperative considerations in alpha-gal syndrome: a review. Cureus, Jan 2024. URL: https://doi.org/10.7759/cureus.53208, doi:10.7759/cureus.53208. This article has 16 citations.
(NCT07611435 chunk 2): Beginning to Assess an Appropriate CONtrol for Oral Food Challenges in Alpha-Gal Syndrome (CoFAR-13) - BeACON4AG. National Institute of Allergy and Infectious Diseases (NIAID). 2026. ClinicalTrials.gov Identifier: NCT07611435
(NCT07177729 chunk 1): The α-gal Syndrome - Investigating Immune Reactions to Tick Bites. Luxembourg Institute of Health. 2025. ClinicalTrials.gov Identifier: NCT07177729