CXCL8 and depressive symptom measurement: Three other studies also observed a significant positive association between IP-10 and depressive symptoms, but findings were limited only to men,39 in a small sample (n = 23),49 or reported only as part of a cluster of biomarkers.66 One study found that IL-8 concentrations were significantly higher amongst people with HIV and remitted depression compared to people with HIV and no depression,39 though several other studies with larger sample sizes did not find a significant association for IL-8.