Vasoactive intestinal peptide regulation of granulomatous inflammation in murine Schistosomiasis mansoni.

Schistosomiasis is a parasitic disease in which focal inflammatory responses called granulomas develop in the liver and intestines. The inflammatory cells within these granulomas produce authentic vasoactive intestine peptide (VIP). VIP acts as an immune modulator. In the schistosome granuloma, VIP can suppress T cell proliferation and T lymphocyte IL-2 production. Also, it can enhance IL-5 production from granuloma T cells. The granuloma T cells bear authentic VIP receptors of both the VIPr1 and VIPr2 subclasses. It is probable that the expression of these receptors is subject to immunoregulation, which is the topic of current investigation. Moreover, differences in the structure of VIPr1 and VIPr2 suggest that each may have unique immunoregulatory functions in inflammation.