Trichosanthin induced Th2 polarization status.

Trichosanthin is extracted from the root tuber of Chinese medicinal herb Trichosanthes kirilowii maximowicz (Tian Hua Fen). TCS has abortifacient, anti-tumor, anti-HIV and immunoregulatory functions. It has been proved that it could inhibit immune response and arouse a T helper 2 response in the draining lymph node. In the current study the effect of TCS on mouse splenocytes was investigated. We stimulated C57BL/6 mice with TCS both in vivo and in vitro and analyzed the change of type 1 and type 2 cytokines in mouse splenocytes. The results showed that TCS could induce the expression of IL-4, one of the major T helper 2 (Th2) cytokines, and inhibit the expression of IFN-gamma, an important Th1 cytokine in spleen lymphocytes both in vivo and in vitro. It is also shown the kinetics of Th1-to-Th2 transition after TCS stimulation in vivo in C57BL/6 mice. We found that type 2 cytokines, such as IL-10, TGF-beta and IL-4 were increased regularly but IFN-gamma was decreased at day 3 and then increased. However the mechanism for cytokine change is not clear.