Biology subjects

Hunt, P. W.

Publications and source records attributed to Hunt, P. W..

9 recordsLinked to original sources

bioRxiv2026

Plasma Proteomic Profiling Identifies a Subset of HIV Elite Controllers with Inflammatory Profiles Resembling People Without HIV

Background: Elite controllers (ECs) are people with HIV (PWH) who suppress viral replication without antiretroviral therapy (ART). A subset, often termed exceptional elite controllers (EECs), harbor very small viral reservoirs, with few intact proviruses integrated into inactive chromosomal regions. Defining inflammatory signatures in ECs may clarify whether some approach a functionally cured state. Methods: We measured 384 plasma proteins in ART-naive ECs (n=62), ART-suppressed non-controllers (n=37), and people without HIV (PwoH) (n=50) using Olink proteomics, and compared proteomic profiles, clinical parameters, and intact reservoir data using FLIP-Seq. Hierarchical clustering identified ECs whose proteomic profiles most closely resembled PWoH; this subset was further analyzed using machine-learning approaches. Results: ART-suppressed non-controllers had higher inflammatory protein levels than ART-naive ECs, yet ECs still showed elevated inflammation and lower CD4:CD8 ratios compared with PWoH. Clustering analysis revealed a distinct subset of ECs (n=9) whose profiles closely matched those without HIV (ECs with PWoH-like proteomic profiles), a pattern not observed in ART-suppressed non-controllers. Compared to typical ECs, ECs with PWoH-like proteomic profiles had consistently lower IL-1{beta}, SCRN1, and BID, numerically lower intact proviral frequencies, and a high frequency of protective HLA alleles. Machine-learning analyses highlighted features that most strongly differentiated ECs with PWoH-like proteomic profiles from typical ECs, including reduced gut mucosal/intestinal epithelial-associated proteins, higher absolute CD4 counts, and lower levels of pro-inflammatory cytokines and cellular immune activation. Conclusions: These findings identify a subset of ECs with a PWoH-like inflammatory proteomic profile, accompanied by numerically lower intact HIV reservoirs and a high frequency of protective HLA alleles. Defining the mechanisms associated with this low-inflammatory state may provide insights into exceptional HIV control and inform strategies for durable HIV remission.

immunology↗

bioRxiv2026

Immune activation during broadly neutralizing antibody-mediated HIV suppression prior to post-intervention control

Broadly neutralizing antibodies (bNAbs) have been associated with enhancement of HIV-specific T or B cell responses and sustained partial control of HIV replication in some people with HIV (PWH). The mechanisms through which bNAbs may potentiate host immunity in this context are not known. We previously reported the outcomes of a clinical trial in which ten PWH on antiretroviral therapy (ART) received a combination of immunotherapies including two bNAbs administered immediately preceding an analytic treatment interruption (ATI). After bNAb levels waned, seven participants exhibited varying degrees of post-intervention control of HIV linked to a robust expansion of activated CD8+ T cells in response to rebounding virus. To investigate the role of the bNAbs in enhancing endogenous immune responses, we looked for evidence of HIV-specific or broader immune activation during the period after ART was paused and prior to rebound when bNAbs were controlling HIV replication. At a timepoint early post-ART interruption and at least one month before virus emerged in plasma, we detected an increase in levels of plasma inflammatory proteins as well as phenotypic and transcriptional activation of innate and adaptive immune cells. Compared to non-controllers, post-intervention controllers demonstrated unique transcriptional activation patterns as well as differential longitudinal plasma inflammatory protein trends. No enhancement of HIV-specific T cell or antibody responses was observed in this window. This study identifies activated cell types and inflammatory pathways that are recruited early during bNAb-mediated HIV suppression and that may play a role in potentiating long-lasting HIV immune control after bNAb therapy. One Sentence SummaryIn a combination immunotherapy trial with high rates of post-intervention control, bNAb-mediated HIV suppression was associated with increased immune activation compared to HIV suppression by ART.

immunology↗

bioRxiv2023

M. tuberculosis antigen-responsive IL17+ CD4 T cells are disproportionately spared in ART-suppressed HIV

BackgroundInterleukin 17 producing CD4 T cells contribute to the control of Mycobacterium tuberculosis (Mtb) infection in humans; whether infection with Human Immunodeficiency Virus (HIV) disproportionately affects distinct Th17 cell subsets that respond to Mtb is incompletely defined. MethodsWe performed high-definition characterization of circulating Mtb-specific Th17 cells by spectral flow cytometry in people with latent TB and treated HIV (HIV-ART). We also measured kynurenine pathway activity by LC/MS on plasma and tested the hypothesis that tryptophan catabolism influences Th17 cell frequencies in this context. ResultsWe identified two subsets of Th17 cells: subset 1 defined as CD4+V7.2-CD161+CD26+ and subset 2 defined as CD4+V7.2-CCR6+CXCR3- cells of which subset 1 was significantly reduced in LTBI with HIV-ART, yet Mtb-responsive IL17-producing CD4 T cells were preserved; we found that IL17-producing CD4 T cells dominate the response to Mtb antigen but not CMV antigen or staphylococcal enterotoxin B (SEB); and tryptophan catabolism negatively correlates with both subset 1 and subset 2 Th17 cell frequencies. ConclusionsWe found differential effects of ART-suppressed HIV on distinct subsets of Th17 cells, that IL17-producing CD4 T cells dominate responses to Mtb but not CMV antigen or SEB, and that kynurenine pathway activity is associated with decreases of circulating Th17 cells that may contribute to tuberculosis immunity.

immunology↗

bioRxiv2021

Host Variation in Interferon, MHC Class I, Glycosylation, and Viral Transcription Genes Predict HIV Persistence

ObjectivePrior genomewide association studies have identified variation in MHC Class I alleles and CCR5{Delta}32 as genetic predictors of viral control, especially in "elite" controllers, individuals who remain virally suppressed in the absence of therapy. DesignCross-sectional genomewide association study. MethodsWe analyzed custom whole exome sequencing and direct HLA typing from 202 ART-suppressed HIV+ non-controllers in relation to four measures of the peripheral CD4+ T cell reservoir: HIV intact DNA, total (t)DNA, unspliced (us)RNA, and RNA/DNA. Linear mixed models were adjusted for potential covariates including age, sex, nadir CD4+ T cell count, pre-ART HIV RNA, timing of ART initiation, and duration of ART suppression. ResultsPreviously reported "protective" host genetic mutations related to viral setpoint (e.g., among elite controllers) were found to predict smaller HIV reservoir size. The HLA "protective" B*57:01 was associated with significantly lower HIV usRNA (q=3.3x10-3), and among the largest subgroup, European ancestry individuals, the CCR5{Delta}32 deletion was associated with smaller HIV tDNA (p=4.3x10-3) and usRNA (p=8.7x10-3). In addition, genomewide analysis identified several SNPs in MX1 (an interferon stimulated gene) that were significantly associated with HIV tDNA (q=0.02), and the direction of these associations paralleled MX1 gene eQTL expression. ConclusionsWe observed a significant association between previously reported "protective" MHC class I alleles and CCR5{Delta}32 with the HIV reservoir size in non-controllers. We also found a novel association between MX1 and HIV total DNA (in addition to other interferon signaling relevant genes, PPP1CB, DDX3X). These findings warrant further investigation in future validation studies.

genomics↗

bioRxiv2021

Distinct cellular immune signatures in acute Zika virus infection are associated withhigh or low persisting neutralizing antibody titers

Although the formation of a durable neutralizing antibody response after an acute viral infection is a key component of protective immunity, little is known about why some individuals generate high versus low neutralizing antibody titers to infection or vaccination. Infection with Zika virus (ZIKV) during pregnancy can cause devastating fetal outcomes, and efforts to understand natural immunity to this infection are essential for optimizing vaccine design. In this study, we leveraged the high-dimensional single-cell profiling capacity of mass cytometry (CyTOF) to deeply characterize the cellular immune response to acute and convalescent ZIKV infection in a cohort of blood donors in Puerto Rico incidentally found to be viremic during the 2015-2016 epidemic in the Americas. During acute ZIKV infection, we identified widely coordinated responses across innate and adaptive immune cell lineages. High frequencies of multiple activated innate immune subsets, as well as activated follicular helper CD4+ T cells and proliferating CD27-IgD-B cells, during acute infection were associated with high titers of ZIKV neutralizing antibodies at 6 months post-infection. On the other hand, low titers of ZIKV neutralizing antibodies were associated with immune features that suggested a cytotoxic-skewed immune "set-point." Our study offers insight into the cellular coordination of immune responses and identifies candidate cellular biomarkers that may offer predictive value in vaccine efficacy trials for ZIKV and other acute viral infections aimed at inducing high titers of neutralizing antibodies. One Sentence SummaryMass cytometry reveals acute ZIKV infection cellular immune signatures that predict high or low neutralizing antibody titers 6 months post-infection.

immunology↗

bioRxiv2020

The Atlas of the In Vivo HIV CD4 T Cell Reservoir

ABSTRACTThe latent reservoir is a main barrier for curing HIV. But because latently-infected cells cannot be phenotyped directly, the features of the in vivo reservoir have remained elusive. Here, we describe a method that leverages high-dimensional phenotyping using CyTOF to trace latently-infected cells reactivated ex vivo to their original pre-activation states. Our results suggest that contrary to common assumptions, the reservoir is not randomly distributed among cell subsets, and is remarkably conserved between individuals. However, reservoir composition differs between tissues and blood, as do cells successfully reactivated by different latency reversing agents. Most importantly, by selecting 8-10 of our 39 original CyTOF markers, we were able to isolate highly purified populations of unstimulated in vivo latent cells, thereby validating the PP-SLIDE approach for reservoir characterization. These purified populations were highly enriched for replication-competent and intact provirus, transcribed HIV, and displayed clonal expansion. The ability to isolate unstimulated latent cells from infected individuals enables previously impossible studies of HIV persistence.Competing Interest StatementThe authors have declared no competing interest.View Full Text

immunology↗

bioRxiv2020

TCF-1 regulates the stem-like memory potential of HIV-specific CD8+ T cells in elite controllers

Although many HIV cure strategies seek to expand HIV-specific CD8+ T cells to control the virus, all are likely to fail if cellular exhaustion is not prevented. A loss in stem-like memory properties (i.e., the ability to proliferate and generate secondary effector cells) is a key feature of exhaustion; little is known, however, about how these properties are regulated in human virus-specific CD8+ T cells. We found that virus-specific CD8+ T cells from humans and non-human primates naturally controlling HIV/SIV infection express more of the transcription factor, TCF-1, than non-controllers. HIV-specific CD8+ T cell TCF-1 expression correlated with memory marker expression and proliferative capacity and declined with antigenic stimulation. CRISPR-Cas9 editing of TCF-1 in human primary T cells demonstrated a direct role in regulating expansion capacity. Collectively, these data suggest that TCF-1 controls the stem-like memory properties of HIV-specific CD8+ T cells and provides a rationale for enhancing this pathway in T cell-based therapeutic strategies for HIV. One Sentence SummaryTCF-1 is highly expressed in HIV-specific CD8+ T cells from elite controllers and directly regulates human CD8+ T cell expansion capacity in response to T cell receptor stimulation.

immunology↗

bioRxiv2019

Class of antiretroviral drugs and anemia risk in the current treatment era

OBJECTIVESAnemia is common among people living with HIV (PLWH) and has been associated with certain, often older, antiretroviral medications. Information on current antiretroviral therapy (ART) and anemia is limited. The objectives were to compare associations between anemia incidence or hemoglobin change with core ART classes in the current ART era.\n\nDESIGNRetrospective cohort study.\n\nSETTINGU.S.-based prospective clinical cohort of PLWH aged 18 and above receiving care at 8 sites between 1/2010-3/2018.\n\nPARTICIPANTS16,505 PLWH were included in this study.\n\nMAIN OUTCOME MEASURESAnemia risk and hemoglobin change were measured for person-time on a protease inhibitor (PI) or an integrase strand transfer inhibitor (INSTI), relative to a non-nucleoside reverse transcriptase inhibitor (NNRTI) reference. We also examined PLWH on multiple core classes. Cox proportional hazards regression analyses were conducted to measure associations between time-updated ART classes and incident anemia or severe anemia. Linear mixed effects models were used to examine relationships between ART classes and hemoglobin change.\n\nRESULTSDuring a median of 4.9 years of follow-up, 1,040 developed anemia and 488 developed severe anemia during. Compared to NNRTI use, INSTI-based regimens were associated with an increased risk of anemia (adjusted hazard ratio [aHR] 1.17, 95% confidence interval [CI] 0.94-1.47) and severe anemia (aHR1.55 95%CI 1.11-2.17), and a decrease in hemoglobin level. Time on multiple core classes was also associated with increased anemia risk (aHR 1.30, 95%CI 1.06-1.60) and severe anemia risk (aHR 1.35, 95%CI 0.99-1.85), while no associations were found for PI use.\n\nCONCLUSIONThese findings suggest INSTI use may increase the risk of anemia. If confirmed, screening for anemia development in users of INSTIs may be beneficial. Further research into underlying mechanisms is warranted.\n\nStrengths and limitations of this studyO_LIThis study utilized a large and geographically diverse population of PLWH in care across the U.S.\nC_LIO_LIThis study leveraged comprehensive clinical data, including information on diagnoses, medication use, laboratory test results, demographic information, and medical history.\nC_LIO_LIThis study investigated associations between specific types of ART core regimens and anemia risk.\nC_LIO_LIThis observational study is subject to residual confounding.\nC_LIO_LIThis study focused on anemia assessed from hemoglobin lab values taken at regular medical care visits without excluding participants with conditions strongly associated with hemoglobin level through non-traditional HIV mechanisms.\nC_LI

epidemiology↗

bioRxiv2018

Association between chronic hepatitis C virus infection and myocardial infarction in people living with HIV in the United States

Hepatitis C virus (HCV) is common among people living with HIV (PLWH). The potential for extrahepatic manifestations of HCV, including myocardial infarction (MI), is a topic of active research. MI is classified into types, predominantly atheroembolic Type 1 MI (T1MI) and supply-demand mismatch Type 2 MI (T2MI). We examined the association between HCV and MI in the CFAR Network of Integrated Clinical Systems (CNICS), a multi-center clinical cohort of PLWH. MIs were centrally adjudicated and categorized by type using the Universal MI definition. We estimated the association between chronic HCV (RNA+) and time to MI adjusting for demographic characteristics, cardiovascular risk factors, clinical characteristics and substance use. Among 24,755 PLWH aged [≥]18, there were 336 T1MI and 330 T2MI during a median of 4.2 years of follow-up. HCV was associated with a 68% greater risk of T2MI (adjusted hazard ratio (aHR) 1.68, 95% CI: 1.22, 2.30) but not T1MI (aHR 0.96, 95% CI: 0.63, 1.45). In a cause-specific analysis of T2MI, HCV was associated with a 2-fold greater risk of T2MI attributed to sepsis (aHR 2.26, 95% CI: 1.34, 3.81). Extrahepatic manifestations of HCV in this high-risk population are an important area for continued research.

epidemiology↗