On the other hand, cytokines secretion activity by these cells is increased; for example, IL-8, IL-10, and tumor necrosis factor (TNF)-α are found in peritoneal fluid of endometriosis patients at greater levels than fertile women (66); thus, macrophages could promote and sustain an inflammatory environment required for endometriosis progress (67). The gene discussed is CXCL8; the disease is endometriosis.