Abstract
Due to the widespread use of antiretroviral therapy, HIV replication is effectively controlled in infected individuals.
However, viral reservoirs form early post-infection, posing a persistent challenge to complete virus eradication.
It has been suggested that sex differences may influence the establishment of HIV reservoirs, with variations
between women and men attributed to socio-economic and biological factors, a phenomenon further
compounded by opioid use. Established knowledge indicates that women are more susceptible to HIV acquisition
than men due to robust estrogen receptor signaling. Despite this, women tend to exhibit lower viral loads and
more robust antiviral responses than men, potentially contributing to differences in the size of viral reservoirs.
Moreover, opioid abuse remains a significant problem among HIV-infected individuals, with common opioids like
morphine implicated in differentially augmenting SIV/HIV persistence within the Central Nervous System (CNS)
and periphery. The overarching goal of this proposal is to explore the role of sex differences in the establishment
and maintenance of HIV/SIV reservoirs in the context of substance use. Preliminary studies using SIV-infected
rhesus macaques as a model of HIV infection demonstrate that chronic use of morphine modulates SIV
reservoirs differentially. Higher reservoir sizes are observed in CNS-derived microglial cells compared to
peripheral PBMC and lymph nodes in animals exposed to morphine, as opposed to control animals. However,
systematic studies are needed to document these differences comprehensively. To address this question, we
plan to utilize age/sex-matched rhesus macaques and unique reagents prepared in our laboratory. This involves
employing a well-established model of the SIVmac251 virus, which has been previously used to generate
preliminary data, demonstrating efficient replication in both the CNS and periphery. The proposed research aims
to delineate the role of sex factors in seeding and establishing viral reservoirs (Aim 1). Subsequently, we will
determine the location, abundance, and persistence of viral reservoirs in the context of opioid dependence.
Modeling simulations will be performed to understand the differences between establishing reservoirs in males
and females (Aim 2). These studies are expected to reveal whether sex differences play a significant role in
establishing reservoirs in people living with HIV infection (PLWH) in the setting of opioid usage. This information
will be valuable for designing effective HIV cure strategies.