Circulating plasma-derived extracellular vesicles expressing bone and kidney markers are associated with neurocognitive impairment in people living with HIV.

Background: Although effective antiretroviral therapy (ART) has improved the life expectancy of people with HIV (PWH), the prevalence of milder forms of HIV-associated neurocognitive disorders (HAND) persist, and it is associated with systemic and neuro-inflammatory processes that could impact other organ systems. However, the complex signaling mechanisms between the bone-kidney systems and the brain in HAND remain unknown. Extracellular vesicles (EVs) play a potential role in inter-organ communication and are involved in regulating cell activity in distant tissues. In this study, we examined whether levels of EVs from bone-and kidney-related cells associate with cognitive dysfunction and explored the relationship between kidney-bone EV axis in PWH experiencing cognitive deficits. Methods: EV subtypes were characterized in plasma from 61 PWH with either cognitive impairment (CI, n = 53) or normal cognition (NC, n = 8) based on the American Academy of Neurology criteria for HIV-associated dementia (HAD, n = 11), minor cognitive motor disorder (MCMD, n = 25) or asymptomatic neurocognitive impairment (ANI, n = 17) by spectral flow cytometry. EVs were profiled with markers reflecting bone and kidney cell origin. A support vector machine learning-based model was employed for analyses of EV phenotypes to predict the cognitive dysfunction. Results: Plasma-EVs expressing osteocalcin, sclerostin, and nephrin were significantly higher in the cognitive impairment group compared to the normal cognition group. EVs bearing kidney cell markers correlated significantly with bone-derived EVs. A machine learning-based model, comprised of osteocalcin+, nephrin+, and CD24+ EVs predicted cognitive impairment in PWH on ART. Conclusion: Our study reveals that neurocognitive impairment in PWH is associated with increased levels of plasma EVs enriched with the bone markers osteocalcin and sclerostin and the kidney marker nephrin, suggesting that these EV subtypes may be novel candidate biomarkers for disease-spanning neurocognitive dysfunction. Moreover, the relationship between bone-derived EVs with kidney-derived EVs may suggest their role in mediating inter-organ crosstalk in the pathogenesis of HIV-associated cognitive impairment.

Plasma CD16+ Extracellular Vesicles Associate with Carotid Artery Intima-Media Thickness in HIV+ Adults on Combination Antiretroviral Therapy.

HIV-infected individuals have increased risk for cardiovascular disease (CVD) despite suppressive antiretroviral therapy (ART). This is likely a result of persistent immune activation and systemic inflammation. Extracellular vesicles (EVs) have emerged as critical mediators of intercellular communication and may drive inflammation contributing to CVD. EVs were characterized in plasma from 74 HIV-infected individuals on combination antiretroviral therapy (cART) and 64 HIV-uninfected controls with paired carotid intima-media thickness (cIMT) assessment. EVs were profiled with markers reflecting lymphoid, myeloid, and endothelial origin. Seventeen plasma inflammatory biomarkers were also assessed. Human umbilical vein endothelial cell (HUVEC) apoptosis was quantified after EV exposure. A significant correlation was observed in HIV-infected participants between cIMT and EVs expressing CD16, and the monocyte-related markers CD4, CD14, and CX3CR1 showed a similar but nonsignificant association with cIMT. No significant correlation between cIMT measurements from HIV-uninfected individuals and EVs was observed. Levels of serum amyloid A, C-reactive protein, and myeloperoxidase significantly correlated with CD14+, CD16+, and CX3CR1+ EVs. No correlation was noted between cIMT and soluble inflammatory markers. HUVECs showed increased necrosis after exposure to the EV-containing fraction of plasma derived from HIV-infected individuals compared to uninfected controls. Our study reveals that EVs expressing monocyte markers correlated with cIMT in HIV-infected individuals on cART. Moreover, EV fractions derived from HIV-infected individuals lead to greater endothelial cell death via necrotic pathways. Collectively, EVs have potential as biomarkers of and therapeutic targets in the pathogenesis of CVD in the setting of treated HIV disease. IMPORTANCE HIV-infected individuals have a 2-fold-increased risk of cardiovascular disease compared with the general population, yet the mechanisms underlying this comorbidity are unclear. Extracellular vesicles have emerged as important mediators in cell-cell communication and, given what we know of their biology, may drive inflammation contributing to cardiovascular disease in this vulnerable population.

Comparative Analysis of Extracellular Vesicles in Patients with Severe and Mild Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Myalgic encephalomyelitis, or chronic fatigue syndrome (ME/CFS) is a serious disease whose cause has yet to be identified. Objective markers of the disease are also not well understood and would serve as important tools in diagnosis and management. One potential biomarker or transmitter of immune signals in ME/CFS is the extracellular vesicle (EV) compartment. These small, membrane bound particles have been shown to play a key role in intercellular signaling. Our laboratory has focused on methods of detection of EVS in clinical samples. In this study we explored whether the prevalence of EVs in the plasma of participants with mild or severe ME/CFS differed from the plasma of healthy control participants. By staining for multiple cell surface molecules, plasma EVs could be fingerprinted as to their cell of origin. Our study revealed a significant correlation between severe ME/CSF and levels of EVs bearing the B cell marker CD19 and the platelet marker CD41a, though these changes were not significant after correction for multiple comparisons. These findings point to potential dysregulation of B cell and platelet activation or homeostasis in ME/CFS, which warrants validation in a replication cohort and further exploration of potential mechanisms underlying the association.

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 proinflammatory 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 the semen of HIV-infected individuals. We report here that fractionated SP enriched for EVs from HIV-infected men induces potent transcriptional responses in epithelial and stromal cells that interface with the luminal contents of the female reproductive tract. Semen EV fractions from acutely infected individuals induced a more proinflammatory signature than those from uninfected individuals. This was not associated with any observable differences in the surface phenotypes of the vesicles. However, microRNA (miRNA) expression profiling analysis revealed that EV fractions from infected individuals exhibit a broader and more diverse profile than those from uninfected individuals. Taken together, our data suggest that SP EVs from HIV-infected individuals exhibit unique miRNA signatures and exert potent proinflammatory transcriptional changes in cells of the female reproductive tract, which may facilitate HIV transmission.IMPORTANCE Seminal plasma (SP), the major vehicle for HIV, can modulate HIV transmission risk through a variety of mechanisms. Extracellular vesicles (EVs) are extremely abundant in semen, and because they play a key role in intercellular communication pathways and immune regulation, they may impact the likelihood of HIV transmission. However, little is known about the properties and signaling effects of SP-derived EVs in the context of HIV transmission. Here, we conduct a phenotypic, transcriptomic, and functional characterization of SP and SP-derived EVs from uninfected and HIV-infected men. We find that both SP and its associated EVs elicit potent proinflammatory transcriptional responses in cells that line the genital tract. EVs from HIV-infected men exhibit a more diverse repertoire of miRNAs than EVs from uninfected men. Our findings suggest that EVs from the semen of HIV-infected men may significantly impact the likelihood of HIV transmission through multiple mechanisms.

Seminal plasma promotes decidualization of endometrial stromal fibroblasts in vitro from women with and without inflammatory disorders in a manner dependent on interleukin-11 signaling.

STUDY QUESTION: Do seminal plasma (SP) and its constituents affect the decidualization capacity and transcriptome of human primary endometrial stromal fibroblasts (eSFs)? SUMMARY ANSWER: SP promotes decidualization of eSFs from women with and without inflammatory disorders (polycystic ovary syndrome (PCOS), endometriosis) in a manner that is not mediated through semen amyloids and that is associated with a potent transcriptional response, including the induction of interleukin (IL)-11, a cytokine important for SP-induced decidualization. WHAT IS KNOWN ALREADY: Clinical studies have suggested that SP can promote implantation, and studies in vitro have demonstrated that SP can promote decidualization, a steroid hormone-driven program of eSF differentiation that is essential for embryo implantation and that is compromised in women with the inflammatory disorders PCOS and endometriosis. STUDY DESIGN, SIZE, DURATION: This is a cross-sectional study involving samples treated with vehicle alone versus treatment with SP or SP constituents. SP was tested for the ability to promote decidualization in vitro in eSFs from women with or without PCOS or endometriosis (n = 9). The role of semen amyloids and fractionated SP in mediating this effect and in eliciting transcriptional changes in eSFs was then studied. Finally, the role of IL-11, a cytokine with a key role in implantation and decidualization, was assessed as a mediator of the SP-facilitated decidualization. PARTICIPANTS/MATERIALS, SETTING, METHODS: eSFs and endometrial epithelial cells (eECs) were isolated from endometrial biopsies from women of reproductive age undergoing benign gynecologic procedures and maintained in vitro. Assays were conducted to assess whether the treatment of eSFs with SP or SP constituents affects the rate and extent of decidualization in women with and without inflammatory disorders. To characterize the response of the endometrium to SP and SP constituents, RNA was isolated from treated eSFs or eECs and analyzed by RNA sequencing (RNAseq). Secreted factors in conditioned media from treated cells were analyzed by Luminex and ELISA. The role of IL-11 in SP-induced decidualization was assessed through Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas-9-mediated knockout experiments in primary eSFs. MAIN RESULTS AND THE ROLE OF CHANCE: SP promoted decidualization both in the absence and presence of steroid hormones (P < 0.05 versus vehicle) in a manner that required seminal proteins. Semen amyloids did not promote decidualization and induced weak transcriptomic and secretomic responses in eSFs. In contrast, fractionated SP enriched for seminal microvesicles (MVs) promoted decidualization. IL-11 was one of the most potently SP-induced genes in eSFs and was important for SP-facilitated decidualization. LARGE SCALE DATA: RNAseq data were deposited in the Gene Expression Omnibus repository under series accession number GSE135640. LIMITATIONS, REASONS FOR CAUTION: This study is limited to in vitro analyses. WIDER IMPLICATIONS OF THE FINDINGS: Our results support the notion that SP promotes decidualization, including within eSFs from women with inflammatory disorders. Despite the general ability of amyloids to induce cytokines known to be important for implantation, semen amyloids poorly signaled to eSFs and did not promote their decidualization. In contrast, fractionated SP enriched for MVs promoted decidualization and induced a transcriptional response in eSFs that overlapped with that of SP. Our results suggest that SP constituents, possibly those associated with MVs, can promote decidualization of eSFs in an IL-11-dependent manner in preparation for implantation. STUDY FUNDING/COMPETING INTEREST(S): This project was supported by NIH (R21AI116252, R21AI122821 and R01AI127219) to N.R.R. and (P50HD055764) to L.C.G. The authors declare no conflict of interest.

Serum extracellular vesicles expressing bone activity markers associate with bone loss after HIV antiretroviral therapy.

OBJECTIVE: We tested whether bone-related extracellular vesicle phenotypes changed after initiating antiretroviral therapy (ART) and determined whether changes in levels of extracellular vesicles correlated with changes in bone mineral density (BMD). DESIGN: Extracellular vesicle phenotypes were measured in blinded serum samples from 15 adults with HIV at baseline, 1, 3, 6 and 12 months after ART initiation. Not all samples were available at each time point so we averaged early (TP1, 1-3 months) and late (TP2, 6-12 months) time points. METHODS: Extracellular vesicles were stained for osteocalcin (OC), RANKL (CD254), RANK (CD265), M-CSF (macrophage colony stimulating factor), and CD34. Serum OC, procollagen type I N-terminal propeptide (P1NP), and C-terminal telopeptide of type 1 collagen (CTx) were also measured. RESULTS: BMD significantly decreased from baseline to 12 months. Levels of OC+EVs, serum OC, serum P1NP, and CTx were significantly higher at early and late time points compared with baseline. Increases in EVs expressing OC, RANKL, RANK, and CD34 from baseline to TP1 were associated with decreases in total hip BMD from baseline to 12 months. Change in serum OC, P1NP, and CTx from baseline to TP1 or TP2 did not correlate with change in BMD. CONCLUSION: Early changes in extracellular vesicles expressing markers of bone activity were associated with total hip bone loss 12 months after ART initiation. These data suggest that serum extracellular vesicles may serve as novel biomarkers of bone remodeling. Future studies are required to determine if extracellular vesicles contribute to the effects of ART on changes in bone turnover markers and BMD.