Tarumi et al. [45] also reported that IL-9-producing Th cells (but not IL-9 concentrations) were aberrantly higher in the peritoneal fluid of those with endometriosis compared with controls and that it additively stimulated IL-8 expression in the presence of TNF-a in ovarian endometrioma stromal cells. The gene discussed is CXCL8; the disease is endometriosis.