The development of persistent cellular reservoirs of latent human immunodeficiency virus (HIV) is a critical obstacle to viral eradication since viral rebound takes place once anti-retroviral therapy ...(ART) is interrupted. Previous studies show that HIV persists in myeloid cells (monocytes and macrophages) in blood and tissues in virologically suppressed people with HIV (vsPWH). However, how myeloid cells contribute to the size of the HIV reservoir and what impact they have on rebound after treatment interruption remain unclear. Here we report the development of a human monocyte-derived macrophage quantitative viral outgrowth assay (MDM-QVOA) and highly sensitive T cell detection assays to confirm purity. We assess the frequency of latent HIV in monocytes using this assay in a longitudinal cohort of vsPWH (n = 10, 100% male, ART duration 5-14 yr) and find half of the participants showed latent HIV in monocytes. In some participants, these reservoirs could be detected over several years. Additionally, we assessed HIV genomes in monocytes from 30 vsPWH (27% male, ART duration 5-22 yr) utilizing a myeloid-adapted intact proviral DNA assay (IPDA) and demonstrate that intact genomes were present in 40% of the participants and higher total HIV DNA correlated with reactivatable latent reservoirs. The virus produced in the MDM-QVOA was capable of infecting bystander cells resulting in viral spread. These findings provide further evidence that myeloid cells meet the definition of a clinically relevant HIV reservoir and emphasize that myeloid reservoirs should be included in efforts towards an HIV cure.
Neuroimmune activation is a putative driver of cognitive impairment in people with HIV (PWH), even in the age of modern antiretroviral therapy. Nevertheless, imaging of the microglial marker, the 18 ...kDa translocator protein (TSPO), with positron emission tomography (PET) in treated PWH has yielded inconclusive findings. One potential reason for the varied TSPO results is a lack of cell-type specificity of the TSPO target.
11 CCPPC, 5-cyano- N -(4-(4- 11 Cmethylpiperazin-1-yl)-2-(piperidin-1-yl)phenyl) furan-2-carboxaminde, is a radiotracer for use with PET to image the colony stimulating factor 1 receptor (CSF1R). The CSF1R is expressed on microglia and central nervous system macrophages, with little expression on other cell types. We used 11 CCPPC PET in virally-suppressed- (VS)-PWH and HIV-uninfected individuals to estimate the effect sizes of higher CSF1R in the brains of VS-PWH.
Sixteen VS-PWH and 15 HIV-uninfected individuals completed 11 CCPPC PET. 11 CCPPC binding (V T ) in nine regions was estimated using a one-tissue compartmental model with a metabolite-corrected arterial input function, and compared between groups.
Regional 11 CCPPC V T did not significantly differ between groups after age- and sex- adjustment unstandardized beta coefficient ( B ) = 1.84, standard error (SE) = 1.18, P = 0.13. The effect size was moderate Cohen's d = 0.56, 95% confidence interval (CI) -0.16, 1.28), with strongest trend of higher V T in VS-PWH in striatum and parietal cortex (each P = 0.04; Cohen's d = 0.71 and 0.72, respectively).
A group difference in 11 CCPPC V T was not observed between VS-PWH and HIV-uninfected individuals in this pilot, although the observed effect sizes suggest the study was underpowered to detect regional group differences in binding.
Early life trauma (ELT) and HIV are associated with social processing deficits. In people with HIV (PWH), we examined whether facial emotion identification accuracy differs by ELT and whether ...neuroendocrine factors including cortisol, oxytocin (OT), and arginine vasopressin, and/or immune system measures play a role in the ELT-performance association.
We used secondary data from the placebo condition of a pharmacologic challenge study in PWH. Presence of ELT was measured with the Childhood Trauma Questionnaire (at least moderate experiences of sexual, physical, and/or emotional abuse). Social processing was measured with the Facial Emotion Perception Test (FEPT). Salivary immune system measures and cortisol were sampled across a 5-hour study session. Blood was collected at study session start (12 pm ) to measure OT and arginine vasopressin. We examined the association of ELT with FEPT and five biological moderators (from principal components analysis of 12 biomarkers) of ELT-FEPT associations.
Of 58 PWH (42 men; mean standard deviation age = 33.7 8.9 years), 50% endorsed ELT. ELT-exposed PWH demonstrated lower identification accuracy across all emotional expressions (unstandardized β B = 0.13; standard error SE = 0.05; p = .021, d = 0.63) and had higher OT levels compared with ELT-unexposed PWH ( t(1,56) = 2.12, p = .039; d = 0.57). For total accuracy, an OT/C-reactive protein factor moderated the ELT-FEPT association ( B = 0.14; SE = 0.05; p = .014); accuracy was lower in ELT-exposed PWH versus ELT-unexposed PWH when the factor was low but not when high. Similar results were obtained for fearful, neutral, and happy faces ( p values < .05). Regardless of ELT, a myeloid migration (MCP-1/MMP-9) factor was associated with reduced accuracy ( p values < .05).
Our pilot findings suggest that ELT may alter social processing in PWH, and OT and C-reactive protein may be a target for improving social processing in ELT-exposed PWH, and myeloid migration markers may be a target in PWH more generally.
To catalyze severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) research, including development of novel interventive and preventive strategies, the progression of disease was characterized ...in a robust coronavirus disease 2019 (COVID-19) animal model. In this model, male and female golden Syrian hamsters were inoculated intranasally with SARS-CoV-2 USA-WA1/2020. Groups of inoculated and mock-inoculated uninfected control animals were euthanized at 2, 4, 7, 14, and 28 days after inoculation to track multiple clinical, pathology, virology, and immunology outcomes. SARS-CoV-2–inoculated animals consistently lost body weight during the first week of infection, had higher lung weights at terminal time points, and developed lung consolidation per histopathology and quantitative image analysis measurements. High levels of infectious virus and viral RNA were reliably present in the respiratory tract at days 2 and 4 after inoculation, corresponding with widespread necrosis and inflammation. At day 7, when the presence of infectious virus was rare, interstitial and alveolar macrophage infiltrates and marked reparative epithelial responses (type II hyperplasia) dominated in the lung. These lesions resolved over time, with only residual epithelial repair evident by day 28 after inoculation. The use of quantitative approaches to measure cellular and morphologic alterations in the lung provides valuable outcome measures for developing therapeutic and preventive interventions for COVID-19 using the hamster COVID-19 model.
Background. Human immunodeficiency virus (HIV)/hepatitis C virus (HCV) coinfection and elevated interleukin (IL)-18 levels are both associated with enhanced progression of hepatic inflammation and ...increased risk of diabetes, kidney disease, and cardiovascular disease. IL-18 is a proinflammatory cytokine made upon activation of the inflammasome, an innate sensing system. We assessed whether increased IL-18 could explain the increased incidence and progression of inflammatory conditions seen with HIV/HCV coinfection. Methods. Serum samples from 559 subjects with HIV monoinfection, HCV monoinfection, HIV/HCV coinfection, or people who inject drugs with neither infection were tested for IL-18 by enzyme-linked immunosorbent assay and for 16 other analytes by electrochemiluminescence immunoassay. IL-18 levels were measured in 14 additional chronically HCV-infected subjects who developed incident HIV infection to determine if IL-18 increases with coinfection. Results. IL-18 was significantly elevated in coinfected individuals vs both monoinfections (P < .0001) independent of age, sex, and race. IL-18 levels were significantly higher in HIV monoinfection than in HCV monoinfection. High IL-18 levels were correlated with detectable HIV viremia and inversely with CD4 cell count (P < .0001), consistent with HIV activation of the inflammasome resulting in CD4 T-cell depletion. Incident HIV infection of chronically HCV-infected subjects resulted in increased IL-18 (P < .001), while HIV suppression was associated with normal IL-18 levels. Four additional analytes (IP-10, IL-12/23p40, IFN-γ, IL-15) were found to be elevated in HIV/HCV coinfection when compared to both monoinfections. Conclusions. HIV/HCV coinfection results in significantly elevated serum IL-18. The elevated levels of this proinflammatory cytokine may explain the increased incidence and progression of inflammatory illnesses seen in coinfected individuals.
HIV-1 infection persists in humans despite expression of antiviral type 1 interferons (IFN). Even exogenous administration of IFNα only marginally reduces HIV-1 abundance, raising the hypothesis that ...people living with HIV-1 (PLWH) are refractory to type 1 IFN. We demonstrated type 1 IFN refractoriness in CD4+ and CD8+ T cells isolated from HIV-1 infected persons by detecting diminished STAT1 phosphorylation (pSTAT1) and interferon-stimulated gene (ISG) induction upon type 1 IFN stimulation compared to healthy controls. Importantly, HIV-1 infected people who were virologically suppressed with antiretrovirals also showed type 1 IFN refractoriness. We found that USP18 levels were elevated in people with refractory pSTAT1 and ISG induction and confirmed this finding
in CD4+ T cells from another cohort of HIV-HCV coinfected persons who received exogenous pegylated interferon-α2b in a clinical trial. We used a cell culture model to recapitulate type 1 IFN refractoriness in uninfected CD4+ T cells that were conditioned with media from HIV-1 inoculated PBMCs, inhibiting
infection with antiretroviral agents. In this model, RNA interference against USP18 partly restored type 1 IFN responses in CD4+ T cells. We found evidence of type 1 IFN refractoriness in PLWH irrespective of virologic suppression that was associated with upregulated USP18, a process that might be therapeutically targeted to improve endogenous control of infection.
People living with HIV-1 (PLWH) have elevated constitutive expression of type 1 interferons (IFN). However, it is unclear whether this impacts downstream innate immune responses. We identified refractory responses to type 1 IFN stimulation in T cells from PLWH, independent of antiretroviral treatment. Type 1 IFN refractoriness was linked to elevated USP18 levels in the same cells. Moreover, we found that USP18 levels predicted the anti-HIV-1 effect of type 1 IFN-based therapy on PLWH.
, we demonstrated that refractory type 1 IFN responses were transferrable to HIV-1 uninfected target CD4+ T cells, and this phenomenon was mediated by type 1 IFN from HIV-1 infected cells. Type 1 IFN responses were partially restored by USP18 knockdown. Our findings illuminate a new mechanism by which HIV-1 contributes to innate immune dysfunction in PLWH, through the continuous production of type 1 IFN that induces a refractory state of responsiveness.
BACKGROUNDIdentifying a quantitative biomarker of neuropsychiatric dysfunction in people with HIV (PWH) remains a significant challenge in the neuroHIV field. The strongest evidence to date ...implicates the role of monocytes in central nervous system (CNS) dysfunction in HIV, yet no study has examined monocyte subsets in blood as a correlate and/or predictor of neuropsychiatric function in virally suppressed PWH.METHODSIn 2 independent cohorts of virologically suppressed women with HIV (vsWWH; n = 25 and n = 18), whole blood samples were obtained either in conjunction with neuropsychiatric assessments (neuropsychological NP test battery, self-report depression and stress-related symptom questionnaires) or 1 year prior to assessments. Immune cell subsets were assessed by flow cytometry.RESULTSA higher proportion of intermediate monocytes (CD14+CD16+) was associated with lower global NP function when assessing monocytes concurrently and approximately 1 year before (predictive) NP testing. The same pattern was seen for executive function (mental flexibility) and processing speed. Conversely, there were no associations with monocyte subsets and depression or stress-related symptoms. Additionally, we found that a higher proportion of classical monocytes was associated with better cognition.CONCLUSIONAlthough it is widely accepted that lentiviral infection of the CNS targets cells of monocyte-macrophage-microglial lineage and is associated with an increase in intermediate monocytes in the blood and monocyte migration into the brain, the percentage of intermediate monocytes in blood of vsWWH has not been associated with neuropsychiatric outcomes. Our findings provide evidence for a new, easily measured, blood-based cognitive biomarker in vsWWH.FUNDINGR01-MH113512, R01-MH113512-S, P30-AI094189, R01-MH112391, R01-AI127142, R00-DA044838, U01-AI35004, and P30-MH075673.
Type I IFN production is essential for innate control of acute viral infection; however, prolonged high-level IFN production is associated with chronic immune activation in HIV-infected individuals. ...Although plasmacytoid DCs (pDCs) are a primary source of IFN, the mechanisms that regulate IFN levels following the acute phase are unknown. We hypothesized that HIV-specific Ab responses regulate late IFN production. We evaluated the mechanism through which HIV-activated pDCs produce IFN as well as how both monoclonal HIV-specific Abs and Abs produced in natural HIV infection modulated normal pDC sensing of HIV. We found that HIV-induced IFN production required TLR7 signaling, receptor-mediated entry, fusion, and viral uncoating, but not endocytosis or HIV life cycle stages after uncoating. Abs directed against the HIV envelope that do not interfere with CD4 binding markedly enhanced the IFN response, irrespective of their ability to neutralize CD4+ T cell infection. Ab-mediated enhancement of IFN production required Fc γ receptor engagement, bypassed fusion, and initiated signaling through both TLR7 and TLR9, which was not utilized in the absence of Ab. Polyclonal Abs isolated from HIV-infected subjects also enhanced pDC production of IFN in response to HIV. Our data provide an explanation for high levels of IFN production and immune activation in chronic HIV infection.
HIV/HCV coinfection and elevated interleukin (IL)-18 levels are both associated with enhanced progression of hepatic inflammation and increased risk of diabetes, kidney disease, and cardiovascular ...disease. IL-18 is a proinflammatory cytokine made upon activation of the inflammasome, an innate sensing system. We assessed whether increased IL-18 could explain the increased incidence and progression of inflammatory conditions seen with HIV/HCV coinfection.
Serum from 559 subjects with HIV monoinfection, HCV monoinfection, HIV/HCV coinfection, or people who inject drugs with neither infection was tested for IL-18 by ELISA and for 16 other analytes by electrochemiluminescence immunoassay. IL-18 levels were measured in 14 additional chronically HCV infected subjects who developed incident HIV infection to determine if IL-18 increases with coinfection.
IL-18 was significantly elevated in coinfected individuals versus both monoinfections (p<0.0001) independent of age, sex, and race. IL-18 levels were significantly higher in HIV monoinfection than in HCV monoinfection. High IL-18 levels were correlated with detectable HIV viremia and inversely with CD4 count (p<0.0001), consistent with HIV activation of the inflammasome resulting in CD4 T cell depletion. Incident HIV infection of chronically HCV infected subjects resulted in increased IL-18 (p<0.001), while HIV suppression was associated with normal IL-18 levels. Four additional analytes (IP-10, IL-12/23p40, IFNy, IL-15) were found to be elevated in HIV/HCV coinfection when compared to both monoinfections.
HIV/HCV coinfection results in significantly elevated serum IL-18. The elevated levels of this proinflammatory cytokine may explain the increased incidence and progression of inflammatory illnesses seen in coinfected individuals.
Clonal expansion of T cells harboring replication-competent virus has recently been demonstrated in patients on suppressive antiretroviral therapy (ART) regimens. However, there has not been direct ...evidence of this phenomenon in settings of natural control, including in posttreatment controllers who maintain control of viral replication after treatment when ART is discontinued. We present a case of an individual who has had undetectable viral loads for more than 15 years following the cessation of ART. Using near-full-genome sequence analysis, we demonstrate that 9 of 12 replication-competent isolates cultured from this subject were identical and that this identity was maintained 6 months later. A similar pattern of replication-competent virus clonality was seen in a treatment-naive HLA-B*57 elite controller. In both cases, we show that CD8+ T cells are capable of suppressing the replication of the clonally expanded viruses in vitro. Our data suggest that, while clonal expansion of replication-competent virus can present a barrier to viral eradication, these viral isolates remain susceptible to HIV-specific immune responses and can be controlled in patients with long-term suppression of viral replication.
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