CROI 2017 Abstract e-Book

Abstract eBook

Poster and Themed Discussion Abstracts

Poster and Themed Discussion Abstracts

365 EARLY EMERGENCE OF MAC-TROPIC HIV VARIANTS IN BRAIN OF PATIENTS WITH NORMAL NEUROLOGY Maria Paz Gonzalez-Perez , Paul P. Peters, Paul Clapham Univ of Massachusetts, Worcester, MA, USA

Background: Highly mac-tropic R5 variants are predominant in brain tissue of AIDS patients with neuroAIDS including HAD. Proviral load in brain tissue is low before neuro- disease develops making it difficult to amplify HIV env sequences. However, if envs could be amplified, they may provide insights into Env genotypes and properties associated with HIV colonization of brain tissue, before the highly mac-tropic, neurovirulent variants develop. Here, we investigated sequences of HIV-1 envs derived from immune and brain tissue of 12 AIDS patients with normal neurology or minor complications (N/MC), before expressing Envs on pseudoviruses and evaluating their properties. Methods: Envelopes were amplified from DNA or RNA from single genomes present in brain and spleen, bone marrow or plasma. Envs were cloned into the pcDNA 3.1D/V5-His- TOPO and sequenced. Env+ pseudovirions were prepared by cotransfection of env vectors with env- pNL4.3 into 293T cells and titrated on HeLa TZM-BL (CD4+ CCR5+ CXCR4+), HIJ (CD4+ CCR5- CXCR4+) and on macrophages. Phylogenetic analyses were undertaken with MEGA v6. Results: N/MC subjects had lower levels of HIV proviral DNA in the brain, with viral sequences difficult to detect in most subjects. However, a substantial number of envs were amplified from brain tissue DNA and/or RNA of seven subjects. Mac-tropic Envs were detected in brain tissue of four N/MC subjects. These mac-tropic R5 Envs in brain tissue formed distinct phylogenetic clusters frommost non-mac-tropic envs from spleen or brain. PCR of env sequences from brain tissue RNA indicated that there was evidence of active replication in brain tissue of some subjects. Envs from immune tissue of the N/MC subjects were nearly all tightly non-mac-tropic contrasting with our previous data for neuroAIDS subjects where Envs derived from immune tissue mediated a range of macrophage infectivity from background levels to modest infection, with a small number of Envs mediating high macrophage infection. Conclusion: Macrophage-tropic variants are established and likely to be replicating in the brain of a percentage of HIV+ subjects early in disease, well before serious neurological dysfunction becomes apparent. These mac-tropic variants may represent viruses early in their adaptation for infection and replication in brain, perivascular macrophages. Our data provide new insights into HIV replication and evolution of mac-tropic Envs in brain tissue of AIDS patients before the onset of serious neurological complications. 366 BLOOD BRAIN BARRIER FUNCTION, ART NEUROACTIVITY, AND RISK OF CSF HIV ESCAPE Carmela Pinnetti , Massimo Tempestilli, Patrizia Lorenzini, Valentina Fedele, Stefania Carta, Valentina Mazzotta, Chiara Agrati, Adriana Ammassari, Carlo F. Perno, Andrea Antinori Natl Inst for Infectious Diseases, Rome, Italy Background: It is debated whether HIV cerebrospinal fluid (CSF) escape (HIVE) may be linked to patients’ features or to ineffective antiretroviral (ARV) CSF penetration. Aimwas to assess CSF penetration and activity of ARVs and correlation with blood brain barrier (BBB) and to estimate risk and predictors of HIVE. Methods: Retrospective study on CSF/plasma paired samples from HIV+ patients taking cART undergoing lumbar puncture (LP) because neurologically symptomatic or for CNS staging. HIVE was: a) detectable CSF HIV-RNA with concurrent plasma <50 cp/mL; b) CSF HIV-RNA >1.0 log10 higher than in concomitant plasma. ARVs concentrations in CSF and plasma were measured by mass spectrometry methods. CSF/plasma concentration ratio was calculated and 95% CSF inhibitory quotients (IQ95) derived, and considered optimal if >1. Impaired BBB was defined by CSF/plasma albumin quotient x 103 (Qalb), according to age-normalized reference ranges (Reiber, Clin Chem, 1995). Adjusted ORs of HIVE were estimated by fitting a logistic multivariable regression model. Results: 133 CSF/plasma pairs from 120 patients (2000-2014). Male 79.7%; median age 47y (IQR 40-51); CD4 count <200 cells/mm3 47.4%. At LP, 58.7%was on TDF/FTC, 3% ABC/3TC, 10.5% ZDV/3TC, 36.8% EFV, 27.1% LPV/r, 13.5% ATV/r, 11.3% DRV/r. Proportion of samples with IQ95 >1 was lower for LPV/r and ATV/r (p=0.014). After stratification by Qalb, the proportion of CSF with IQ95 >1 in the two strata was still similar for EFV, ATV/r and DRV/r, but not for LPV/r (p=0.05 at interaction test). A positive correlation between Qalb and CSF/plasma ARV concentration ratio (R=0.686, p<0.001) and ARV IQ95 (R=0.658, p<0.001) was found. HIVE was detected in 19/133 samples (14.4%). Only in a subset of 73 asymptomatic pts, duration of current cART [AOR 1.98 per year more (95%CI 1.27-3.12)] and CSF log10 HIV-RNA [AOR 17.91 (95%CI 1.04-307.55)] was associated to an increased HIVE risk by multivariable logistic regression. IQ95 of third drug was not associated with HIVE [AOR 0.84 95%CI 0.20-3.50], whereas Qalb was associated to increased HIVE risk [AOR 5.75; 95%CI 1.10-30.1]. Conclusion: BBB dysfunction may influence neuropenetration (CSF/plasma drug concentration ratio) and efficacy (IQ95) of ARVs and play a role on asymptomatic HIVE mechanism. Despite the fact that action of ARVs in the CNS, except for DRV/r, was far below, the role of drug exposure and activity in CSF on HIVE pathogenesis remains controversial.

CROI 2017 145