Seminal Plasma-Derived Extracellular-Vesicle Fractions from HIV-Infected Men Exhibit Unique MicroRNA Signatures and Induce a Proinflammatory Response in Cells Isolated from the Female Reproductive Tract

The continuing spread of HIV/AIDS is predominantly fueled by sexual exposure to HIV-contaminated semen. Seminal plasma (SP), the liquid portion of semen, harbors a variety of factors that may favor HIV transmission by facilitating viral entry into host cells, eliciting the production of pro-inflammatory cytokines, and enhancing the translocation of HIV across the genital epithelium. One important and abundant class of factors in SP is extracellular vesicles (EVs), which in general are important intercellular signal transducers. Although numerous studies have characterized blood plasma-derived EVs from both uninfected and HIV-infected individuals, little is known about the properties of EVs from semen of HIV-infected individuals. We report here that fractionated SP enriched for EVs from HIV-infected men induce potent transcriptional responses in epithelial and stromal cells that interface with luminal contents of the female reproductive tract. Compared to semen EV fractions from uninfected individuals, those from acutely-infected individuals induced a more pro-inflammatory signature. This was not associated with any observable differences in the surface phenotypes of the vesicles. However, miRNA expression profiling analysis revealed that EV fractions from infected individuals exhibit a broader and more diverse profile. Taken together, our data suggest that SP EVs from HIV-infected individuals exhibit unique miRNA signatures and exert potent pro-inflammatory transcriptional changes in cells of the female reproductive tract, which may facilitate HIV transmission. The seminal plasma-derived microvesicle fractions (from 15 acutely-infected individuals and from 15 uninfected individuals) were assessed for their effects on endometrial stromal fibroblasts (n=3 donors) and endometrial epithelial cells (n=3 donors) by RNAseq.