Final answer:
In Celiac disease, T cells are responsible for recognizing antigens such as gluten, which leads to an autoimmune response damaging the small intestine's microvilli and causing numerous symptoms.
Step-by-step explanation:
In the case of Celiac disease, T cells recognize fragments of gluten, which is a protein present in wheat, barley, and rye. This recognition triggers an immune response that can damage the microvilli lining the small intestine. When microvilli are damaged, it hampers the small intestine's ability to absorb nutrients, leading to the various symptoms associated with Celiac disease such as malnutrition, cramping, and diarrhea. Celiac disease causes many different symptoms and serious complications because the immune response mistakenly targets the body's tissues, leading to widespread inflammation and damage. Other autoimmune diseases that involve the body attacking its digestive system include Crohn's disease and ulcerative colitis. Diagnosis of Celiac disease typically involves serological testing for antibodies like IgA against components of gluten and transglutaminase enzyme, followed by an endoscopy and biopsy of the duodenal mucosa to confirm the presence of intestinal damage.