Unbiased serology reveals autoimmunity and HIV antibody signatures in HIV CNS Escape

Background Antiretroviral therapy (ART) suppresses plasma and cerebrospinal fluid (CSF) HIV replication with occasional asymptomatic episodes of detectable HIV RNA known as asymptomatic (AS) escape. Neurosymptomatic (NS) CSF escape is a rare exception in which CNS HIV replication occurs in the setting of neurologic impairment. The origins of NS escape are not fully understood. Methods Using a large cohort of PLWH (n=111), including elite controllers (n=4), viral controllers (n=4), ART untreated subjects (n=18), HIV-associated dementia (n=4), ART suppressed (n=16), AS escape (n=19), NS escape (n=35), secondary escape (n=5) subjects, and HIV-negative controls (n=6), we investigated immunoreactivity to self-antigens in the CSF of NS escape by employing neuroanatomic CSF immunostaining and massively multiplexed self-antigen serology (PhIP-Seq). Additionally, we utilized pan-viral serology (VirScan) to deeply profile the CSF anti-viral antibody response and metagenomic next-generation sequencing (mNGS) for pathogen detection. Results We detected Epstein-Barr virus (EBV) DNA more frequently in the CSF of NS escape subjects than in AS escape controls. Based on immunostaining and PhIP-Seq, there was evidence for increased immunoreactivity against self-antigens in NS escape CSF. Finally, VirScan revealed several immunodominant epitopes that map to the HIV env and gag proteins in the CSF of PLWH. Discussion We deployed agnostic tools to study whether there was evidence for a neuroinvasive co-infection and/or autoimmunity in HIV escape syndromes. We more frequently detected EBV DNA and immunoreactivity to self-antigens in NS escape. Whether these additional inflammatory markers are byproducts of an HIV-driven inflammatory process or whether they independently contribute to the neuropathogenesis of NS escape will require further study.