Immune profiling of antibodies and B cells that recognize HIV and substances in people who use substances and live with HIV (PWUSH) - SUMMARY In response to NIDA PAS-21-270 AIDS-Science Track Award for Research Transition (R03 Clinical Trial Optional), we propose to investigate how drug abuse may impact antibody response in HIV infection. We have previously shown that chronic Cocaine use increased HIV-associated anti-CD4 autoantibody levels in people with HIV (PWH) on antiretroviral therapy (ART). Through two ongoing study cohorts that collect blood specimens from people who use substance (PWUS) and live with HIV (PWUSH) at the Medical University of South Carolina (MUSC) and Boston Medical Center (BMC), we will have access to de-identified plasma specimens of more than 100 PWH and 100 PWUS, most of them being PWUSH. These study subjects included men and women, as well as more than 50% racial and ethnic minorities reflecting the demographics of the studied populations seen at the MUSC and BMC hospitals. We propose to systematically immune profile their antibody responses to HIV Tat, Nef, and Vpr, which have been documented to contribute to neurotoxicity, neuroinflammation, and HIV- associated neurocognitive disorders (HAND). As substance abuse alone, including the use of Cocaine and Opioids, can cause neurocognitive impairment, and drug abuse has been associated with poor ART adherence and exacerbates HIV disease, we will also immune profile the antibody responses to abused drugs. We propose to analyze the specimens to test the hypothesis that drug abuse alters antibody response in HIV infection, and rare human antibodies are developed in PWH, PWUS, or PWUSH that recognize HIV Tat, Nef, Vpr, or Cocaine and abused Opioids with high affinity and specificity. Aim 1 (Years 1-2) will apply established ELISA to profile plasma antibody binding titers directed to HIV Tat, Nef, and Vpr (subaim 1a) as well as to Cocaine and abused Opioids including Heroin and Fentanyl (subaim 1b). The goals of Aim 1 include: 1) compare antibody titers to the measured HIV antigens between PWH with and without substance use; 2) compare antibody titers to the measured substances between PWUS with and without HIV; 3) identify the top 5% subjects who mounted the highest antibody titers for antigen-specific B cell sorting by FACS in Aim 2 (Year 2). Based on the Aim 1 plasma binding data, up to N = 6 PBMCs will be selected for FACS in Aim 2 to assess the frequency of memory B cells that stain positively for the tested antigens – a step critical to reliably sort antigen-specific B cells for B cell receptor (BCR) sequencing and human monoclonal antibody (mAb) discovery. It would be exciting to immediately identify human mAbs that display the desired specificities; however, such mAb discovery and characterization would likely take a major effort and thus go beyond the scope of the R03. The data and findings from this proposal, however, would likely lead to future R01 applications focusing on the development of antibody-based interventions to specifically improve on meeting the prophylactic and therapeutic needs of the vulnerable PWUSH populations.
