Biomarkers for diagnosis and monitoring of celiac disease.

Celiac disease (CD) is an autoimmune disorder, which damages the small intestine and is caused by ingestion of gluten in genetically susceptible individuals. The only known effective treatment is a lifelong gluten-free diet. Genetic risk factors have been identified and nearly all patients are HLA-DQ2 and/or HLA-DQ8 positive. Specific autoantibodies, IgA antitissue transglutaminase-2, antiendomysium, and antideaminated forms of gliadin peptide antibodies, are widely used as diagnostic aids in celiac patients. However, the discovery of new biomarkers may help in the diagnosis and follow-up of the disease. Recently, the molecule REG Iα, involved in tissue regeneration, has been proposed as a new biomarker of CD. REG Iα expression is increased in the target tissue and in the sera of celiac patients during damage and inflammation, decreasing after gluten-free diet. In this article we review the main biomarkers for diagnosis and monitoring of CD, focusing on the immune response-related mechanisms.

Urinary levels of regenerating protein Iα do not differentiate celiac patients and healthy subjects.

Celiac disease is an autoimmune disorder induced by gluten in genetically predisposed people. The discovery of new biomarkers may help in the diagnosis and follow-up of celiac patients. Regenerating islet-derived 1 alpha (REGIα)--a biomarker related to tissue regeneration--is increased in serum at the onset of the disease, decreasing after gluten-free diet (GFD). As REGIα is a 18 kDa soluble glycoprotein, it may be detected in urine samples, increasing in celiac patients. We have determined REGIα levels by ELISA. No differences were found among patients (onset or after GFD) and controls and no correlation exists among REGIα in sera and urine.