Immunological aspects in chronic inflammatory bowel disease

Aetiology as well as pathogenesis of Crohn's disease and ulcerative colitis are unclear as yet. Recent studies suggest that a transmissible factor present in Crohn's disease lymph nodes produces lymphoma and immune complex glomerulonephritis in nu/nu mice. Furthermore, sera of those patients contain an antibody, that recognizes an "antigen(s)" in the murine lymphoma and glomerular immune complexes. Contrary to earlier reports up to date knowledge gives no indication for a primary immunological defect of functions of the cell mediated immunity or unspecific immune system, although impairment of some immunological parameters appears due to the disease, both in Crohn's disease and in ulcerative colititis. This holds true for peripheral blood mononuclear cells. Results obtained with mononuclear cells isolated from the gut are highly controversial and at present do not allow final conclusions.