Elevated sCD163 in plasma but not cerebrospinal fluid is a marker of neurocognitive impairment in HIV infection

Abstract

Objective: Here we evaluated whether neurocognitive disorders in HIV-infected individuals on effective antiretroviral therapy (ART) are associated with persistent monocyte activation as indexed by levels of soluble CD163 (sCD163), shed by monocyte/macrophages. Design: Chronically, HIV-infected individuals were examined at two consecutive visits median [interquartile range (IQR)] 16 (7–32) months apart. All patients were on ART and durably virologically suppressed (plasma HIV RNA P = 0.028]. Patients with MND (N = 6) had significantly higher plasma sCD163 than ANI (P = 0.04) or NP-nml (P = 0.02). Whereas plasma sCD163 levels dropped in patients who were stably GDS-unimpaired after the first visit (P < 0.032), levels remained elevated in those who remained GDS-impaired (P = 0.50). Interpretation: These findings are consistent with persistent monocyte/macrophage activation in neurophysiologically impaired HIV-infected individuals despite virally suppressive ART. Overall, these observations underscore the significance of monocyte/macrophage immune responses in HIV, persistent monocyte activation in HAND and the value of sCD163, as a plasma marker of neurocognitive impairment.