antigen presentation
Start with the article narrative. Use the right sidebar to jump from prose into concept context, nearby graph relationships, and source provenance.
The decisive adaptive step: gluten becomes visible to the immune system only after it is processed, modified, and displayed in the right genetic context.
Antigen presentation is the bridge between gluten exposure and the full adaptive immune response. In celiac disease, the key logic is:
gliadin peptide -> modification by tissue transglutaminase -> binding to HLA-DQ2/DQ8 -> recognition by CD4+ T cells
Core Components
gliadin and other prolamins
These are the incoming food-derived proteins. Because they resist digestion, unusually large peptides survive long enough to enter the mucosal immune environment.
tissue-transglutaminase and deamidation
Tissue transglutaminase changes gluten peptides chemically. Deamidation makes them bind much more strongly to HLA-DQ2/DQ8.
Antigen-presenting cells
Dendritic cells and related immune cells pick up peptide material and display it using MHC class II molecules. In celiac disease, the clinically important MHC class II variants are HLA-DQ2/DQ8.
CD4+ T cells
Once the peptide-HLA complex is displayed, CD4+ T cells recognize it and drive the adaptive inflammatory cascade.
Why Genetics Matters So Much
HLA-DQ2/DQ8 does not cause disease by itself. Rather, it creates the presentation platform that makes the wrong gluten peptides look highly persuasive to T cells.
That is why these alleles are:
- close to necessary for classic celiac disease
- still not sufficient on their own
- central to both diagnosis and treatment research
Relationship to the Rest of the Lesion
Antigen presentation sits upstream of several downstream events:
- cytokines amplify inflammation
- il-15 drives an innate epithelial stress axis
- intraepithelial lymphocytes expand
- villous atrophy and crypt hyperplasia emerge
Why This Node Matters for Therapeutics
This is one of the cleanest intervention points in the whole construct:
- block peptide formation
- block peptide display
- block T-cell recognition
- induce tolerance induction instead of activation
That is why so much research converges on HLA, epitopes, and antigen-specific immune retraining.
Related Concepts
mechanism | hla-dq2-dq8 | tissue-transglutaminase | deamidation | cd4-t-cells | tolerance-induction
Source Basis
Compiled from the current wiki corpus, especially mechanism, causes, hla-dq2-dq8, deamidation, and cd4-t-cells.