According to the National Health and Nutrition Examination Survey study of the Center for Disease Control, approximately 1 in 141 people have celiac disease in North America, and around 80% of people who could have the disease have yet to be diagnosed (Fasano & Catassi, 2001). There is currently no cure for this disease. The only known treatment is a strict diet that eliminates gluten. It is known that dietary proteins are degraded enzymatically into amino acids, and these digestive enzymes are produced in the stomach, pancreas, and small intestine. Upon entering the small intestine, polypeptides are further digested by pancreatic enzymes, such as Trypsin, chymotrypsin, and carbozypeptidases A & B (Dennis, 2014). Unfortunately, in the stomach and small intestines of those with celiac disease, a problem occurs and they are unable to completely digest the gluten proteins that enter their digestive system. But, as the pathophysiology and biochemistry of celiac disease is becoming better understood, new methods of treatments, specifically orally active drugs, are being developed. .
Celiac disease, also known as celiac sprue or gluten sensitive enteropathy, is a hereditary autoimmune disorder in which gluten, which can be found in wheat, rye or barley, damages the lining of the small intestine and creates inflammation (Trier, 1991). Normally, enzymes in the stomach break down gluten into peptides, but in those who suffer from celiac disease, these peptides trigger an autoimmune response with painful symptoms (Dennis, 2014). The toxic factors of gluten are found in the storage proteins. In all toxic proteins, there are unique structural features that have sequence domains rich in the amino acids Gln and Pro (Wieser & Koehler, 2008). The high content of Pro makes the proteins resistant to entire proteolytic digestion by gastrointestinal enzymes. Therefore, the large Pro- and Gln-rich peptides are gathered in the small intestine (Wieser & Koehler, 2008).