Protein P37 of mycoplasma hyorhinis induces secretion of TNF-α from human peripheral blood mononuclear cells

摘要

High mycoplasmal infection ratio in gastric cancer tissues suggests a possible association between mycoplasma infection and tumorigenesis. Because TNF-α plays an important role in carcinogenesis caused by microbes infection and P37 is a major immunogen of mycoplasma hyorhinis (M. hyor.), investigating whether P37 could induce expression and secretion of TNF-α will be very significant to elucidate the possible molecular mechanism of gastric carcinogenesis involved with M.hyor. At the present study, we cloned full gene of p37 by PCR and mutated the 7 codes of TGA into TGG first, then expressed the P37 protein successfully with pGEX-4T-1 vector in E. coli, which was verified with Western blot. By RT-PCR and sensitive L929 cell toxic assay, we found that P37 protein could induce expression and secretion of TNF-α from human peripheral blood mononuclear cells, and the inducing activity of P37 could be dramatically blocked by McAb PD4. These results suggest that the induction of TNF-α secretion by P37 probably plays an important role in diseases caused by M. hyor. infection and needs to be further investigated.