Final answer:
T cells that encounter gluten antigen in celiac disease are primarily Th1 helper T cells, which produce an immune response resulting in inflammation and mucosal damage in the small intestine. These cells are involved in cellular immune responses that drive the celiac disease pathology.
Step-by-step explanation:
T cells that have encountered gluten antigen are typically associated with celiac disease, a condition characterized by an immune response to the presence of gluten. When gluten is ingested, it is modified by the enzyme tissue transglutaminase, leading to the production of peptides that trigger an immune response in genetically predisposed individuals. Gluten-specific T cells are usually of the helper T cell subtype, referred to as Th1 cells, which release cytokines that activate other immune system components, resulting in tissue inflammation and damage, particularly in the small intestine.
Diagnosis of celiac disease involves serological tests for detecting IgA antibodies to gluten and tissue transglutaminase. In addition, an endoscopy with biopsy may be conducted to assess the damage to the duodenal mucosa. Celiac disease is just one example of an autoimmune condition; others include diabetes mellitus type I, which targets the beta cells of the pancreas, and certain thyroid disorders affected by antibodies to the thyroid-stimulating hormone receptor.