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Background The risk of severe COVID-19 varies significantly among persons of similar age and is higher in males. Age-independent, sex-biased differences in susceptibility to severe COVID-19 may be ascribable to deficits in a sexually dimorphic protective attribute that we termed immunologic resilience (IR). Objective To examine whether deficits in IR that antedate or are induced by SARS-CoV-2 infection independently predict COVID-19 mortality. Methods IR levels were quantified with two novel metrics: immune health grades (IHG-I [best] to IHG-IV) to gauge CD8+ and CD4+ T-cell count equilibrium, and blood gene expression signatures. IR metrics were examined in a prospective COVID-19 cohort (n=522); primary outcome was 30-day mortality. Associations of IR metrics with outcomes in non-COVID-19 cohorts (n=13,461) provided the framework for linking pre-COVID-19 IR status to IR during COVID-19, as well as to clinical outcomes. Results IHG-I, tracking high-grade equilibrium between CD8+ and CD4+ T-cell counts, was the most common grade (73%) among healthy adults, particularly in females. SARS-CoV-2 infection associated with underrepresentation of IHG-I (21%) vs. overrepresentation (77%) of IHG-II or IHG-IV, especially in males vs. females (P Conclusion Preservation of immunocompetence with controlled inflammation during antigenic challenges is a hallmark of IR and associates with longevity and AIDS resistance. Independent of age, a male-biased proclivity to degrade IR before and/or during SARS-CoV-2 infection predisposes to severe COVID-19. Clinical implications Biomarkers tracking immunologic resilience may have broad prognostic utility, as they associated with longevity, as well as resistance to a progressive disease course during SARS-CoV-2, influenza, or HIV infection.

Summary Background Few large projects have evaluated the factors that influence the HIV RNA concentrations (viral load) in cerebrospinal fluid (CSF) during antiretroviral therapy (ART) over time. We aimed to determine the correlates of HIV RNA in CSF in a large cohort. Methods We analysed longitudinal data from adults living with HIV in the US CHARTER cohort. Participants in the CHARTER study were recruited from six US academic medical centres—in Baltimore (MD), Galveston (TX), New York (NY), St Louis (MO), San Diego (C92A), and Seattle (WA). Participants in this study had been assessed at least three times between Sept 4, 2003, and Sept 14, 2010, and were taking ART and underwent venous and lumbar puncture with measurement of HIV RNA concentration at all assessments. The lower limit of quantification of the HIV RNA assays was 50 copies per mL. Data were analysed with longitudinal mixed effects logistic regression to identify correlates of HIV RNA concentration (as a binary [detectable or not] and as a continuous variable) in CSF over time. We tested demographic characteristics, plasma HIV RNA, nadir and current CD4 cell count in blood, current CD8 cell count in blood, estimated duration of HIV infection, AIDS diagnosis, duration of ART, adherence to ART, ART characteristics, and CSF characteristics as potential correlates. Findings At the time of analysis, 2207 assessments from 401 participants met the criteria for inclusion in this study. Mean duration of observation was 33·7 months (range 12–84). HIV RNA concentrations in 710 (32·2%) plasma specimens and in 255 (11·6%) CSF specimens were greater than the lower limit of quantification. The best multivariate model of HIV RNA concentration in CSF greater than the lower limit of quantification over time included increased plasma HIV RNA concentration (odds ratio 18·0 per 1 log10 copy per mL, 95% CI 11·3 to 28·8; p Interpretation The identified correlates of HIV RNA concentration in CSF during ART could strengthen clinical prediction of risk for failure to achieve or maintain HIV RNA suppression in CSF. Because most participants in this analysis were ART-experienced and were taking a three-drug regimen that did not include an integrase inhibitor, future research should focus on participants who are taking their first ART regimens or regimens that include integrase inhibitors or two drugs. Funding The work was supported by the National Institute of Mental Health and the National Institute of Neurological Disorders and Stroke.

While human immunodeficiency virus (HIV) infection has become a treatable disease with the development of combination antiretroviral therapy (cART), chronic inflammation that affects the central nervous system and other organs is still common. Reliable methods are needed to study HIV-associated inflammatory biomarkers. In this study involving both plasma and cerebrospinal fluid (CSF), we compared multiplex bead array (MBA) to a relatively new technology based on microfluidics and glass nanoreactor (GNR) technology for the measurement of three commonly studied markers from HIV-infected individuals. We found that results correlated between the two platforms for MCP-1 in both fluids as well as for plasma TNFα (all p

There is mounting evidence that prospective memory (PM) is impaired during HIV infection despite treatment. In this prospective study, 66 adults (43 HIV+ and 23 HIV negative) underwent PM assessment and cerebrospinal fluid (CSF) examination. HIV+ participants had significantly lower PM but significantly higher CSF concentrations of CXCL10 and quinolinic acid (QUIN). Higher CSF phosphorylated Tau (pTau) was associated with worse PM. In a secondary analysis excluding outliers, higher QUIN correlated with higher pTau. CSF QUIN is thus elevated during HIV infection despite antiretroviral therapy and could indirectly contribute to impaired PM by influencing the formation of pTau.

The soluble membrane attack complex (sMAC) represents the terminal product of the complement cascade. We enrolled 47 HIV + adults (12 of whom underwent a second visit at least 24 weeks after starting therapy) as well as 11 HIV negative controls. At baseline, cerebrospinal fluid (CSF) sMAC was detectable in 27.7% of HIV + individuals. CSF sMAC correlated with CSF HIV RNA levels and was more likely to be detectable in HIV + individuals on cART compared to HIV negative controls. In HIV + participants, there were negative association trends between sMAC and neurocognitive performance but these did not reach statistical significance.

We hypothesized that humoral immunity stimulation in the CNS in HIV-1C patients would be lower than that in HIV-1B due to a defective Tat chemokine dimotif (C30C31) that might influence cellular trafficking and CNS inflammation. Sixty-eight paired CSF and blood samples from people with HIV (PWH), free of CNS opportunistic infections, were included, HIV-1B (n = 27), HIV-1C (n = 26), and HIV negative (n = 25). IgG intrathecal synthesis was assayed using quantitative and qualitative methods. IgG oligoclonal bands (OCB) in CSF were observed in 51% of PWH, comparable between HIV-1B and HIV-1C, as well as the medians of IgG intrathecal synthesis formulas. The group with HIV infection aviremic in CSF and blood showed 75% of OCB. There was a poor positive correlation between the IgG quotient and GDS. The impact of HIV-1 on IgG intrathecal production was not subtype dependent. Low-grade CNS intrathecal IgG production persists in HIV CNS infection even in PWH with CSF and blood HIV RNA controlled.

HIV infection and methamphetamine (METH) use are highly comorbid and represent a significant public health problem. Both conditions are known to negatively impact a variety of brain functions. One brain function that may be affected by HIV and METH use is sensorimotor gating, an automatic, pre-conscious filtering of sensory information that is thought to contribute to higher order cognitive processes. Sensorimotor gating is often measured using prepulse inhibition (PPI), a paradigm that can be conducted in both humans and animals, thereby enabling cross-species translational studies. While previous studies suggest HIV and METH may individually impair PPI, little research has been conducted on the effects of combined HIV and METH on PPI. The goal of this cross-species study was to determine the effects of METH on PPI in the inducible Tat (iTat) mouse model of HIV and in people with HIV. PPI was measured in the iTat mouse model before, during, and after chronic METH treatment and after Tat induction. Chronic METH treatment decreased PPI in male but not female mice. PPI normalized with cessation of METH. Inducing Tat expression decreased PPI in male but not in female mice. No interactions between chronic METH treatment and Tat expression were observed in mice. In humans, HIV was associated with decreased PPI in both men and women. Furthermore, PPI was lowest in people with HIV who also had a history of METH dependence. Overall, these results suggest HIV and METH may additively impair early information processing in humans, potentially affecting downstream cognitive function.HIGHLIGHTSHIV decreased PPI in men and womenPPI was most decreased in people with HIV and a history of METH dependenceChronic METH treatment decreased PPI in male but not female miceTat expression decreased PPI in male but not female miceChronic METH treatment and Tat expression did not interact to affect PPI in mice

Prior research has demonstrated neuropsychological (NP) impairment in persons with histories of injection drug use (IDU), hepatitis C virus (HCV) infection, and methadone maintenance treatment (MMT), individually, but little is known about the NP effects of these three risk factors in combination. This issue is particularly important in China, which is addressing its highly HCV-comorbid IDU epidemic with widespread government sponsored MMT, especially in light of recent evidence suggesting that methadone may be neuroprotective in some circumstances.We administered a comprehensive NP test battery to 195 Chinese heroin IDU individuals taking MMT (IDU+ group), the majority of whom were also HCV+ (87%; n=169), and compared their NP performance to that of 198 demographically comparable, non-IDU Chinese controls (IDU- group). All participants in both groups tested negative for HIV infection, which is also a common comorbidity in the Chinese IDU population.The IDU+ group did not have an increased rate of global NP impairment, or perform significantly worse on any individual NP test measure. Within the IDU+ group, liver disease characteristics and reported details of heroin use were not significantly associated with NP performance.Failure to detect NP impairment in IDU+ subjects with or without HCV infection was surprising, particularly considering the previously demonstrated sensitivity of our NP battery to neurocognitive disorders associated with HIV infection in China. One possible explanation, which should be explored in future research, is the potential neuroprotective effect of methadone in the context of HCV infection and/or heroin withdrawal.

The neuropathogenesis of HIV associated neurocognitive disorders (HAND) involves disruption of mitochondrial homeostasis and increased neuroinflammation. However, it is unknown if alterations in mitochondrial biogenesis in the brain underlie the neuropathogenesis of HAND. In this study, neuropathological and molecular analyses of mitochondrial biogenesis and inflammatory pathways were performed in brain specimens from a well-characterized cohort of HIV+ cases that were on antiretroviral regimens. In vitro investigations using primary human astroglia and neurons were used to probe the underlying mechanisms of mitochondrial alterations. In frontal cortices from HAND brains compared to cognitive normal brains, total levels of transcription factors that regulate mitochondrial biogenesis, peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) and transcription factor A, mitochondrial (TFAM) were decreased. Immunohistochemical analyses revealed that TFAM was decreased in neurons and increased in astroglia. These changes were accompanied by decreased total mitochondrial DNA per cell and increased levels of messenger RNA for the proinflammatory cytokine interleukin (IL)-1β. To determine how IL-1β affects astroglial bioenergetic processes and mitochondrial activity, human astroglial cultures were exposed to recombinant IL-1β. IL-1β induced mitochondrial activity within 30 min of treatment, altered mitochondrial related gene expression, altered mitochondrial morphology, enhanced adenoside triphosphate (ATP) utilization and increased the expression of inflammatory cytokines. WIN55,212-2 (WIN), an aminoalkylindole derivative and cannabinoid receptor agonist, blocked IL-1β-induced bioenergetic fluctuations and inflammatory gene expression in astroglia independent of cannabinoid receptor (CB)1 and peroxisome proliferator-activated receptor (PPAR) γ. A PPARα antagonist reversed the anti-inflammatory effects of WIN in human astroglia. These results show that mitochondrial biogenesis is differentially regulated in neurons and astroglia in HAND brains and that targeting astroglial bioenergetic processes may be a strategy to modulate neuroinflammation.

Standard methods used to estimate HIV-1 population diversity are often resource intensive (e.g., single genome amplification, clonal amplification and pyrosequencing) and not well suited for large study cohorts. Additional approaches are needed to address the relationships between intraindividual HIV-1 genetic diversity and 2 disease. With a small cohort of individuals, we validated three methods for measuring diversity: Shannon entropy and average pairwise distance (APD) using single genome sequences, and counts of mixed bases (i.e. ambiguous nucleotides) from population based sequences. In a large cohort, we then used the mixed base approach to determine associations between measure HIV-1 diversity and HIV associated disease. Normalized counts of mixed bases correlated with Shannon Entropy at both the nucleotide (rho=0.72, p=0.002) and amino acid level (rho=0.59, p=0.015), and APD (rho=0.75, p=0.001). Among participants who underwent neuropsychological and clinical assessments (n=187), increased HIV-1 population diversity was associated with both a diagnosis of AIDS and neuropsychological impairment.

Methamphetamine (meth) abuse is increasingly of public health concern and has been associated with neurocognitive dysfunction. Some previous studies have been hampered by background differences between meth users and comparison subjects, as well as unknown HIV and hepatitis C (HCV) status, which can also affect brain functioning. We compared the neurocognitive functioning of 54 meth dependent (METH+) study participants who had been abstinent for an average of 129 days, to that of 46 demographically comparable control subjects (METH-) with similar level of education and reading ability. All participants were free of HIV and HCV infection. The METH+ group exhibited higher rates of neuropsychological impairment in most areas tested. Among meth users, neuropsychologically normal (n=32) and impaired (n=22) subjects did not differ with respect to self-reported age at first use, total years of use, route of consumption, or length of abstinence. Those with motor impairment had significantly greater meth use in the past year, but impairment in cognitive domains was unrelated to meth exposure. The apparent lack of correspondence between substance use parameters and cognitive impairment suggests the need for further study of individual differences in vulnerability to the neurotoxic effects of methamphetamine.

BackgroundWhen antiretroviral therapy does not fully suppress HIV replication, suboptimal levels of antiretrovirals can select for antiretroviral resistant variants of HIV. These variants may exhibit reduced replication capacity and result in lower viral loads in blood. Our study evaluated whether antiretroviral resistance was associated with viral loads in the cerebrospinal fluid (CSF) and better neuropsychological (NP) performance.MethodsWe enrolled 94 participants and each participant underwent a comprehensive neuromedical evaluation that used structured clinical assessments of medical history, ART and other medication use, comprehensive NP testing, and neurological and general physical signs of disease. Blood was collected by venipuncture, and all participants were offered lumbar puncture. Univariate and multivariate statistical methods were used to analyze the relationship between antiretroviral resistance, blood and CSF HIV RNA levels, substance use, and NP performance.ResultsAntiretroviral resistance, detected in blood, was associated with lower CSF viral loads (p

Introduction: We hypothesized that pleocytosis, which is a marker of central nervous system (CNS) inflammation, would result in viral genetic equilibration or de-compartmentalization between HIV populations in the blood and cerebrospinal fluid (CSF), suggesting viral trafficking. Methods : Study subjects, who started or interrupted their antiretroviral treatment, had viral loads measured and clonal viral env sequences generated from HIV RNA extracted from paired blood and CSF samples. White blood counts in CSF were also measured at each timepoint. Degree of inter-compartment segregation was calculated by posterior probability using linear discriminant analysis and multidimensional scaling. Co-receptor usage was determined using a trained support vector machine. Results : Pleocytosis was strongly associated with disruption of viral compartmentalization. Conclusions : Inflammation in the CNS, marked by pleocytosis, allows HIV populations to mix between blood and CSF, which may increase the overall viral genetic diversity within the CSF.

Although monocyte chemoattractant protein (MCP-1)/CCL2 is believed to mediate trafficking of HIV-activated leukocytes into the CNS, its role has not been studied directly in humans. To evaluate MCP-1's effects on CNS leukocyte infiltration, we measured CSF leukocytes and MCP-1 levels in serial plasma and cerebrospinal fluid (CSF) samples from subjects who experienced large increases in viral load after interrupting antiretrovirals. Following large increases in CSF MCP-1, CSF leukocytosis (15–166 cells/μL) developed in 4 of 6 subjects. Both initial MCP-1 levels and subsequent changes were 3-fold larger in CSF than plasma. The magnitude and timing of changes suggested that MCP-1 triggers the development of CSF pleocytosis.

Because monocyte chemotactic protein (MCP)-1 is an important cofactor in HIV neuropathogenesis, we investigated the relationship between MCP-1 genotype and expression in cerebrospinal fluid (CSF). We evaluated a genetic polymorphism in the MCP-1 promoter at position -2578 (alternatively designated -2518) in 98 HIV-infected subjects who had contemporaneously collected plasma and CSF. CSF MCP-1 levels were highest in the G/G genotype group, intermediate in the G/A group, and lowest in the A/A group. MCP-1 levels in plasma only differed by genotype after adjusting for HIV-related factors. Our findings suggest that this MCP-1 promoter polymorphism influences HIV neuropathogenesis by regulating MCP-1 protein expression in the central nervous system (CNS).

Previous studies of HIV-associated neurocognitive disease (HAND) have focused on the role of monocytes/macrophages. Having observed that high CD8 levels are a risk factor for HAND and hypothesizing that cerebrospinal fluid (CSF) could be a portal of entry for activated CD8 T-cells, we investigated cytokine responses by CSF T-cells. HIV+ participants with and without HAND were treated with CNS-penetrating anti-retroviral agents. CSF cells and PBMCs were harvested before treatment and at 6 and 16 weeks post-treatment and assessed for intracellular expression of IL-2, IFNg and TNFa, in response to HIV antigens. Data were examined both longitudinally (16 subjects with 3 visits) and cross-sectionally (30 subjects, total 59 visits). Overall, CD4 and CD8 T-cells in the CSF were more likely to make all three cytokines than CD4 and CD8 T-cells in blood. Impairment was associated with higher levels of constitutive and HIV-induced IFNg (p = .04) and TNFa (p = .05) expression by CD8 T-cells in the CSF. While higher levels of HIV RNA in CSF suppressed CD8 cytokine expression in unimpaired subjects, impaired subjects persisted with high cytokine expression regardless of RNA levels (p = .04). In addition to identifying a novel mechanism of HIV pathogenesis, these findings validate viral suppression in both CSF and the periphery as an important treatment goal for HAND, but also suggest that modulation of the CD8 T-cell response may be required.