Peritoneal natural killer cell chemotaxis is decreased in women with pelvic endometriosis.

In women with endometriosis, not only cytotoxicity but also chemotaxis by NK cells in peritoneal cavity is significantly decreased, and particularly chemotaxis is decreased throughout the menstrual cycle. Therefore, antigens in retrograde menstrual blood that enters the peritoneal cavity might be left unprocessed. Repetition of this immune process in the peritoneal cavity may lead to the onset and subsequent progression of endometriosis.