[Changes in NK activities and TGF- beta concentrations in the peritoneal cavity in endometriosis and their...

The purpose of this study was to clarify the relationship between NK activity and TG-beta in the immune system in endometriosis. We investigated (1) the changes in the NK activity and concentration of TGF-beta in human peritoneal fluid (HPF), and (2) the effects of HPF and TGF-beta on the development of early mice embryos. In a rat model of experimental endometriosis, we observed the effects of tissue culture supernatants of peritoneum on NK activity in rat spleen cells, and obtained the following results. (1) NK activity of peripheral lymphocytes in healthy women was significantly suppressed in the presence of HPF of endometriosis. (2) The concentrations of TGF-beta was significantly higher in HPF of endometriosis than in HPF of healthy women. (3) Both HPF of endometriosis and TGF-beta significantly inhibited the development of early mice embryos. (4) The supernatants prepared from the intact peritoneum of the rat model showed marked inhibition of NK activity compared to control rats, although the peritoneum was obtained from a region distant from the implanted endometrium. These results suggest that ectopic endometrial tissues may cause a change in the cell-mediated immune system and subsequently exert an adverse effect on human reproduction.