We conclude that endometriotic cells have not changed the immunophenotype of peripheral lymphocytes, and the extent of the microenvironmental impact of endometrial foci is probably local and affects the peritoneal fluid, in which differentiated expression of anti-inflammatory cytokines, including TGF-β1, is observed in women with endometriosis [89]. The gene discussed is TGFB1; the disease is endometriosis.