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Biology subjects

Reyes-Teran, G.

Publications and source records attributed to Reyes-Teran, G..

7 recordsLinked to original sources

Selective infection and loss of PRDM1+ LN Tfh cells in uncontrolled HIV infection precludes formation of Tfh reservoirs under ART

The multifaceted and long-lived nature of HIV-1 reservoirs has proven to be a formidable obstacle in the development of a therapeutic cure of HIV-1. One of the major dimensions of the HIV-1 reservoir is its prevalence and persistence in tissue environments, including in lymph nodes (LN). Within LN, T follicular helper (Tfh) cells are widely considered as the dominant sub-reservoir in viremic people with HIV (PWH). However, whether Tfh cells survive to establish a reservoir in PWH undergoing suppressive antiretroviral therapy (ART) has remained controversial. To address these issues, we deeply phenotyped over 500,000 cells and identified over 2,000 HIV-1 infected cells by employing single-cell multiomics on LN from PWH during viremia and suppressed on ART. While we detected HIV-1 infected Tfh cells, the majority of infected cells during viremia and ART had non-follicular phenotypes and were instead heterogeneously distributed between various CD4+ T-cell subsets. Within-subset comparisons of HIV+ and HIV- cells revealed heightened activation signatures and altered cell cycle states during viremia, but largely similar features during ART. Furthermore, the comparison between viremia and ART in PWH highlighted a noncanonical Tfh subset - defined by high locus accessibility and transcription of PRDM1 - that is selectively depleted during viremia, recovers after ART, and is highly susceptible to infection in vitro. Our work suggests a revised direction for the HIV-1 cure field where a mandate of any comprehensive strategy will be to address the high proportional burden of non-follicular cells within the HIV reservoir.

immunology↗

Neutralization activity in chronic HIV infection is characterized by a distinct programming of follicular helper CD4 T cells

A subset of people living with HIV (PLWH) can produce broadly neutralizing antibodies (bNAbs) against HIV, but the lymph node (LN) dynamics that promote the generation of these antibodies are poorly understood. Here, we explored LN-associated histological, immunological, and virological mechanisms of bNAb generation in a cohort of anti-retroviral therapy (ART)-naive PLWH. We found that participants who produce bNAbs, termed neutralizers, have a superior LN-associated B cell follicle architecture compared with PLWH who do not. The latter was associated with a significantly higher in situ prevalence of Bcl-6hi follicular helper CD4 T cells (TFH), expressing a molecular program that favors their differentiation and stemness, and significantly reduced IL-10 follicular suppressor CD4 T cells. Furthermore, our data reveal possible molecular targets mediating TFH-B cell interactions in neutralizers. Together, we identify cellular and molecular mechanisms that contribute to the development of bNAbs in PLWH.

immunology↗

Extensive heterogeneity of the HIV-1 infected CD4+ T-cell reservoir revealed by single-cell viral ASAPseq

Understanding the complexity of the long-lived HIV reservoir during antiretroviral therapy (ART) remains a major impediment for HIV cure research. To address this, we developed single-cell viral ASAPseq to precisely define the unperturbed peripheral blood HIV-infected memory CD4+ T cell reservoir from antiretroviral treated people living with HIV (ART-PLWH) via the presence of integrated accessible proviral DNA in concert with epigenetic and cell surface protein profiling. We identified profound reservoir heterogeneity within and between ART-PLWH, characterized by novel and known surface markers within total and individual memory CD4+ T cell subsets. We further uncovered novel epigenetic profiles and transcription factor motifs enriched in HIV-infected cells that suggest infected cells with accessible provirus, irrespective of reservoir distribution, are poised for reactivation during ART treatment. Together, our findings reveal the extensive inter- and intrapersonal cellular heterogeneity of the HIV reservoir, and establish an initial multiomic atlas to develop targeted reservoir elimination strategies.

microbiology↗

Schizophrenia risk from locus-specific human endogenous retroviruses

Schizophrenia genome-wide association studies highlight the substantial contribution of risk attributed to the non-coding genome where human endogenous retroviruses (HERVs) are encoded. These ancient viral elements have previously been overlooked in genetic and transcriptomic studies due to their poor annotation and repetitive nature. Using a new, comprehensive HERV annotation, we found that the fraction of the genome where HERVs are located (the retrogenome) is enriched for schizophrenia risk variants, and that there are 148 disparate HERVs involved in susceptibility. Analysis of RNA-sequencing data from the dorsolateral prefrontal cortex of 259 schizophrenia cases and 279 controls from the CommonMind Consortium showed that HERVs are actively expressed in the brain (n = 3,979), regulated in cis by common genetic variants (n = 1,759), and differentially expressed in patients (n = 81). Convergent analyses implicate LTR25_6q21 and ERVLE_8q24.3h as HERVs of etiological relevance to schizophrenia, which are co-regulated with genes involved in neuronal and mitochondrial function, respectively. Our findings provide a strong rationale for exploring the retrogenome and the expression of these locus-specific HERVs as novel risk factors for schizophrenia and potential diagnostic biomarkers and treatment targets.

neuroscience↗

Mapping the lineage relationship between CXCR5+ and CXCR5- CD4+ T cells in HIV infected human lymph nodes

CXCR5 is a key surface marker expressed on follicular helper T (TFH) cells. We report here B cell help functionality in a population of CD4+ T cells isolated from primary human lymph nodes (LN) that lacked CXCR5 expression. This CXCR5- subset is distinguished from other CXCR5- CD4+ T cells by high PD-1 expression. Accumulation of CXCR5-PD-1+ T cells correlated with peripheral CD4+ T cell depletion and an increase in T-bet+ B cells in the LN, highlighting these atypical CD4+ T cells as a key component of lymphoid dysregulation during chronic HIV infection. By interrogating the phenotypic heterogeneity, functional capacity, TCR repertoire, transcriptional profile, and epigenetic state of CXCR5-PD-1+ T cells, we showed that CXCR5-PD-1+ T cells are related to CXCR5+PD-1+ T cells and provided evidence for the down regulation of CXCR5 following cell division as one mechanism for the absence of CXCR5 expression. Notably, CXCR5-PD-1+ T cells exhibited a migratory transcriptional program and contributed to circulating CXCR5-PD-1+ T cells with B cell help functionality in the peripheral blood. Thus, these data link LN pathology to circulating T cells and expand the current understanding on T cell diversity in the regulation of B cell responses during chronic inflammation. O_LIHigh dimensional profiling of activated CD4+ T cells in HIV infected lymph nodes revealed an accumulation of a CXCR5 negative subset. C_LIO_LICXCR5-PD-1+CD4+ T cells exhibited TFH-like protein expression and function. C_LIO_LICXCR5-PD-1+CD4+ T cells are related to TFH cells by clonal lineage and epigenetic similarity. C_LIO_LICXCR5-PD-1+CD4+ T cells upregulate a migratory gene program and contribute to circulating T cells with B cell help functionality C_LI

immunology↗

Characterization of intact proviruses in blood and lymph node from HIV-infected individuals undergoing analytical treatment interruption

The role of lymphoid tissue as a potential source of HIV-1 rebound following interruption of antiretroviral therapy is uncertain. To address this issue, we compared the latent viruses obtained from CD4+ T cells in peripheral blood and lymph nodes to viruses emerging during treatment interruption. Latent viruses were characterized by sequencing near full-length (NFL) proviral DNA, and env from viral outgrowth cultures (VOAs). 5 HIV-1 infected individuals on antiretroviral therapy (ART) were studied, 4 of whom participated in a clinical trial that included an analytical treatment interruption. Intact or replication competent clonal sequences from blood and lymph node overlapped. In contrast, there was no overlap between 205 latent reservoir and 125 rebound sequences in the 4 individuals who underwent treatment interruption. However, rebound viruses could be accounted for by recombination. The data suggests that CD4+ T cells carrying latent viruses circulate between blood and lymphoid tissues in individuals on ART and support the idea that recombination may play a role in the emergence of rebound viremia.

clinical trials↗

Telescope: Characterization of the retrotranscriptome by accurate estimation of transposable element expression

Characterization of Human Endogenous Retrovirus (HERV) expression within the transcriptomic landscape using RNA-seq is complicated by uncertainty in fragment assignment because of sequence similarity. We present Telescope, a computational software tool that provides accurate estimation of transposable element expression (retrotranscriptome) resolved to specific genomic locations. Telescope directly addresses uncertainty in fragment assignment by reassigning ambiguously mapped fragments to the most probable source transcript as determined within a Bayesian statistical model. We demonstrate the utility of our approach through single locus analysis of HERV expression in 13 ENCODE cell types. When examined at this resolution, we find that the magnitude and breadth of the retrotranscriptome can be vastly different among cell types. Furthermore, our approach is robust to differences in sequencing technology, and demonstrates that the retrotranscriptome has potential to be used for cell type identification. Telescope performs highly accurate quantification of the retrotranscriptomic landscape in RNA-seq experiments, revealing a differential complexity in the transposable element biology of complex systems not previously observed. Telescope is available at github.com/mlbendall/telescope.\n\nAuthor SummaryAlmost half of the human genome is composed of Transposable elements (TEs), but their contribution to the transcriptome, their cell-type specific expression patterns, and their role in disease remains poorly understood. Recent studies have found many elements to be actively expressed and involved in key cellular processes. For example, human endogenous retroviruses (HERVs) are reported to be involved in human embryonic stem cell differentiation. Discovering which exact HERVs are differentially expressed in RNA-seq data would be a major advance in understanding such processes. However, because HERVs have a high level of sequence similarity it is hard to identify which exact HERV is differentially expressed. To solve this problem, we developed a computer program which addressed uncertainty in fragment assignment by reassigning ambiguously mapped fragments to the most probable source transcript as determined within a Bayesian statistical model. We call this program, \"Telescope\". We then used Telescope to identify HERV expression in 13 well-studied cell types from the ENCODE consortium and found that different cell types could be characterized by enrichment for different HERV families, and for locus specific expression. We also showed that Telescope performed better than other methods currently used to determine TE expression. The use of this computational tool to examine new and existing RNA-seq data sets may lead to new understanding of the roles of TEs in health and disease.

genomics↗