Zonulin is a novel human protein analogue to the zonula occludens toxin derived from Vibrio cholerae which participates in tight junctions between cells of the wall of the digestive tract. Zonulin binds to a specific receptor on the surface of intestinal epithelia and triggers a cascade of biochemical events which induces tight junction disassembly and a subsequent permeability increase of the intestinal epithelia, allowing some substances to pass through and activate immune reactions. Fasano and his co-workers found that the zonulin-zonulin-receptor-system is more activated in celiac disease and type 1 diabetes mellitus patients. Patients with active celiac disease showed higher levels of zonulin and anti-zonulin antibodies compared to non-celiac patients and patients in remission, who were on a gluten-free diet. Concerning the autoimmune type 1 diabetes, in experiments with rats it could be demonstrated that elevated zonulin levels as well as increased intestinal permeability precede a type 1 diabetes disease. Conversely, type 1 diabetes could be prevented by inhibition of zonulin in animal experiments. In addition, it was reported that many people who suffer from celiac disease also suffer from other autoimmune disorders. It is suggested that increased levels of zonulin are a contributing factor to the development of celiac disease and other autoimmune disorders such as insulin dependent diabetes, multiple sclerosis and rheumatoid arthritis.
Immundiagnostik AG (www.immundiagnostik.com), founded in 1986 by Dr. Franz Paul Armbruster (CEO), is specialized on the development, production, and world-wide distribution of innovative parameters and detection methods for laboratory diagnostics and medical research. The main focus is the development of immunological tools, of HPLC and molecular biology methods, and of new applications for mass spectrometry (LC-MS/MS). Immundiagnostik concentrates on the development and production of laboratory diagnostics for the identification of disease risks, for differential diagnosis, and for therapeutic drug monitoring. The company holds a particularly strong portfolio in markers of oxidative stress/anti-aging, gastroenterology and nutrition, skeletal system, and cardio-reno-vascular system. Immundiagnostik owns more than 35 patents in Europe, the US, Japan, Canada, and Australia, is certified according to DIN EN ISO 13485 and fulfills the requirements of the German Medical Device Regulation and the EU IVD Regulations (98/79 EG).