Table_1_Circulating plasma-derived extracellular vesicles expressing bone and kidney markers are associated with neurocognitive impairment in people living with HIV.XLSX

BackgroundAlthough 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 PLW experiencing cognitive deficits.MethodsEV 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.ResultsPlasma-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.ConclusionOur 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.</p

Table_1_Comparative Analysis of Extracellular Vesicles in Patients with Severe and Mild Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.pdf

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.</p

Image_1_Circulating brain-derived extracellular vesicles expressing neuroinflammatory markers are associated with HIV-related neurocognitive impairment.tiff

BackgroundNeurocognitive impairment remains prevalent in people with HIV (PWH) despite long term virological suppression by antiretroviral therapy (ART) regimens. Systemic and neuro-inflammatory processes are suggested to contribute to the complex pathology leading to cognitive impairment in this population, yet the underlying mechanisms remain unresolved. Extracellular vesicles (EVs) play a central role in intracellular communication and have emerged as key modulators of immunological and inflammatory responses. In this report, we examined the impact of EVs in PWH experiencing cognitive deficits to determine their relevance in HIV associated neuropathology.MethodsEV phenotypes were measured in plasma samples from 108 PWH with either cognitive impairment (CI, n=92) or normal cognition (NC, n=16) by flow cytometry. Matched cerebrospinal fluid (CSF)-derived EVs were similarly profiled from a subgroup of 84 individuals who underwent a lumbar puncture. Peripheral blood mononuclear cells were assayed by flow cytometry to measure monocyte frequencies in a subset of 32 individuals.ResultsPlasma-EVs expressing CD14, CD16, CD192, C195, and GFAP were significantly higher in HIV-infected individuals with cognitive impairment compared to individuals with normal cognition. Increased CSF-EVs expressing GFAP and CD200 were found in the cognitive impairment group compared to the normal cognition group. Frequencies of patrolling monocytes correlated with plasma-EVs expressing CD14, CD66b, MCSF, MAP2, and GFAP. Frequencies of CD195 expression on monocytes correlated positively with plasma-EVs expressing CD41a, CD62P, and CD63. Expression of CD163 on monocytes correlated positively with CSF-EVs expressing GFAP and CD200. Finally, the expression of CD192 on total monocytes correlated with CSF-EVs expressing CD200, CD62P, and CD63.ConclusionsEVs expressing monocyte activation and neuronal markers associated with HIV associated cognitive impairment, suggesting that distinct EV subsets may serve as novel biomarkers of neuronal injury in HIV infection. Further circulating platelet EV levels were linked to monocyte activation indicating a potential novel interaction in the pathogenesis of HIV-related cognitive impairment.</p

HIV Infectivity of PBMCs from SCD Patients and non-SCD Controls.

CD8-depleted PBMC from SCD patients and non-SCD controls were infected with HIV NL4-3 (CXCR4-tropic) and 81-A (CCR5-tropic) at increasing MOI for six days. Following incubation, supernatants and cells were harvested for detection of HIV p24 (Panel A) and pro-viral load (Panel B) respectively. Mean and standard errors of the means for 30 SCD patients and 30 non-SCD controls are shown. Samples from four SCD patients and two non-SCD controls spanning a range of proviral load were assayed for integrated HIV DNA (Panel C). Five samples showed undetectable HIV DNA on both assays and are not graphed. The linear regression line of the log10 values is shown.</p

Comparison of HIV co-receptors, CD4+ T cell activation markers, CD4+ MFI and Percent of CD4+ Cells Among Total T Cells between SCD patients and non-SCD controls.

Twenty four-hour old whole blood samples from SCD patient and non-SCD controls were labeled for CD4 T cells and incubated with antibodies to detect markers associated with HIV or cellular activation. Following incubation, surface expression of the HIV co-receptors CCR5 and CXCR4 and T cell trafficking molecule CCR7 were measured by flow cytometry (Panel A). MFI, mean fluorescence intensity between SCD patients and non-SCD controls were compared. Percent of CD4+ T cells expressing the activation markers CD38 or HLA-DR were measured and compared between SCD patients and non-SCD controls (Panel B). The intensity of expression of CD4+ amongst T cells (Panel C) and the percent of CD4+ T cells among total T cells (Panel D) was significantly higher in SCD patients compared to non-SCD controls. Mean and standard errors of the means for 30 SCD patients and 30 non-SCD controls are shown, *p<0.05.</p

Cytokines and Chemokines Compared between SCD Patients (treated or not treated with HU) and non-SCD Controls.

Biomarkers tested are grouped into anti-inflammatory (AI), chemoattractant (CA), coagulation (CO), growth factor (GF) and pro-inflammatory (PI) functional categories. Relative increases in concentration are shown in red and decreases in blue. * significantly different between SCD patients and non-SCD controls (p<0.05 after FDR correction).</p

Odds of HIV Acquisition in TSS.

Odds of HIV Acquisition in TSS.</p

Demographics of 30 SCD Subjects Prospectively Enrolled to Investigate Mechanisms of Resistance to HIV.

Demographics of 30 SCD Subjects Prospectively Enrolled to Investigate Mechanisms of Resistance to HIV.</p

HIV Infectivity of Target MT-2 cells in the Presence of Plasma from SCD Patients or Plasma from Non-SCD Controls.

MT-2 cells maintained at log phase growth were infected with either HIV NL4-3 (Panel A) or 81-A virus (Panel B) at MOI of 10−2 in cultures spiked with 20% plasma from SCD patients or non-SCD controls. Following 7-day infections supernatants were measured for p24 by ELISA. Mean and SEM are shown. * p<0.05.</p

Baseline characteristics of participants in the transfusion safety study at study entry, by HIV status.

Baseline characteristics of participants in the transfusion safety study at study entry, by HIV status.</p