The Role Of T Help Cells And B7 Molecules In The Pathogenesis Of DSS Induced Murine Colitis

Background and Aims:Ulcerative colitis is a chronic nonspecific colonic inflammatory disease. It is commonly recognized that aberrant immune status plays an important role in the pathogenesis of UC. T help cell is the important regulatory and effective cell in the immune response. It has been shown that the imbalanced Th1 and Th2 subsets are associated with the abnormal immune status in various diseases. There has been shown that imbalanced Th1 and Th2 subsets may also exist in UC patients, but whether Th1 response or Th2 response predominance in UC is not yet clear. B7-1 and B7-2 belong to the member of B7 molecules family, which are the important costimulatory molecules involving in T cell activation. It has been proved that abnormal expression of B7-1 and B7-2 may be the important factor that causes the imbalanced Th1/Th2 and immune disturbance in some autoimmue diseases, however the role of B7 molecules in UC is not clarified. It has been reported that DSS induced murine colitis is one of the ideal animal models used to investigate UC. In order to determine the role of Th1/Th2 cell subset and B7-1/B7-2 molecule at different stage of colitis, the acute and chronic DSS-induced murine colitis models would be established, and then the ratio of Th1/Th2 and the expression of B7-1/B7-2 would be investigated in this study.