Biology subjects

Dutra, J.

Publications and source records attributed to Dutra, J..

5 recordsLinked to original sources

bioRxiv2026

Neutralizing vaccination against viral interleukin-6 from a primate rhadinovirus

Herpesviruses are ancient viruses that devote a significant fraction of their protein-coding potential to interference with host immunity. Diverse herpesviruses encode proteins with similarity to host MHC molecules, interferon regulatory factors, complement regulators, G-protein coupled receptors, chemokines, and cytokines. Certain gammaherpesviruses, including Kaposi sarcoma-associated herpesvirus (KSHV) and rhesus rhadinovirus (RRV), encode viral cytokines similar to host IL-6, called viral IL-6 (vIL-6). The potential of vIL-6 to act as a protective vaccine antigen against these rhadinoviruses remains under-explored. We isolated a new RRV strain, which encodes virion surface proteins similar to those of previous isolates and a vIL-6 that is nearly identical. We found that, although unmodified vIL-6 is a poor immunogen eliciting low neutralizing titers, vIL-6-Fc fusion protein elicits high-titer responses after either one or two doses. We detected no adverse effects related to cytokine activity, nor interference with concomitantly administered vaccine against the RRV glycoprotein B. Our results demonstrate an approach for eliciting neutralizing antibodies against a highly conserved viral protein that contributes to rhadinovirus persistence and oncogenesis.

immunology↗

bioRxiv2023

SIV clearance from neonatal macaques following transient CCR5 depletion

SUMMARY PARAGRAPHTreatment of people with HIV (PWH) with antiretroviral therapy (ART) results in sustained suppression of viremia, but HIV persists indefinitely as integrated provirus in CD4-expressing cells. Intact persistent provirus, the "rebound competent viral reservoir" (RCVR), is the primary obstacle to achieving a cure. Most variants of HIV enter CD4+ T cells by binding to the chemokine receptor, CCR5. The RCVR has been successfully depleted only in a handful of PWH following cytotoxic chemotherapy and bone marrow transplantation from donors with a mutation in CCR5. Here we show that long-term SIV remission and apparent cure can be achieved for infant macaques via targeted depletion of potential reservoir cells that express CCR5. Neonatal rhesus macaques were infected with virulent SIVmac251, then treated with ART beginning one week after infection, followed by treatment with either a CCR5/CD3-bispecific or a CD4-specific antibody, both of which depleted target cells and increased the rate of plasma viremia decrease. Upon subsequent cessation of ART, three of seven animals treated with CCR5/CD3-bispecific antibody rebounded quickly and two rebounded 3 or 6 months later. Remarkably, the other two animals remained aviremic and efforts to detect replication-competent virus were unsuccessful. Our results show that bispecific antibody treatment can achieve meaningful SIV reservoir depletion and suggest that functional HIV cure might be achievable for recently infected individuals having a restricted reservoir.

immunology↗

bioRxiv2023

Inducing an oxidized redox-balance improves anti-tumor CD8+ T cell function

Cancer immunotherapy using antigen-specific CD8+ T cells depends on long-lasting anti-tumor function of the in vitro expanded T cells. T cell function is intricately linked to the activity of many metabolic pathways directly impacting the ability of CD8+ T cells to kill tumor cells. Metabolic conditioning in vitro better prepares CD8+ T cells for in vivo survival, tumor infiltration and tumor clearance. The mechanism underlying in vitro metabolic conditioning-induced augmented in vivo T cell function remains poorly understood. Here we show that metabolic conditioning of CD8+ effector T cells induces an oxidized cellular redox balance at least in part mediated by increased mitochondrial reactive oxygen species (ROS). This redox shift contributes to enhanced in vivo persistence and tumor clearance. In human tumour-infiltrating T cells, altering the redox balance ex-vivo reinvigorated pro-inflammatory cytokine production. Therefore, we believe that redox alterations present a targetable pathway to increase T cell-based anti-tumor immunotherapy efficacy.

immunology↗

bioRxiv2021

Early post-infection treatment of SARS-CoV-2 infected macaques with human convalescent plasma with high neutralizing activity reduces lung inflammation

Early in the SARS-CoV-2 pandemic, there was a high level of optimism based on observational studies and small controlled trials that treating hospitalized patients with convalescent plasma from COVID-19 survivors (CCP) would be an important immunotherapy. However, as more data from controlled trials became available, the results became disappointing, with at best moderate evidence of efficacy when CCP with high titers of neutralizing antibodies was used early in infection. To better understand the potential therapeutic efficacy of CCP, and to further validate SARS-CoV-2 infection of macaques as a reliable animal model for testing such strategies, we inoculated 12 adult rhesus macaques with SARS-CoV-2 by intratracheal and intranasal routes. One day later, 8 animals were infused with pooled human CCP with a high titer of neutralizing antibodies (RVPN NT50 value of 3,003), while 4 control animals received normal human plasma. Animals were monitored for 7 days. Animals treated with CCP had detectable levels of antiviral antibodies after infusion. In comparison to the control animals, they had similar levels of virus replication in the upper and lower respiratory tract, but had significantly reduced interstitial pneumonia, as measured by comprehensive lung histology. By highlighting strengths and weaknesses, data of this study can help to further optimize nonhuman primate models to provide proof-of-concept of intervention strategies, and guide the future use of convalescent plasma against SARS-CoV-2 and potentially other newly emerging respiratory viruses. Author summaryThe results of treating SARS-CoV-2 infected hospitalized patients with COVID-19 convalescent plasma (CCP), collected from survivors of natural infection, have been disappointing. The available data from various studies indicate at best moderate clinical benefits only when CCP with high titer of neutralizing antibodies was infused early in infection. The macaque model of SARS-CoV-2 infection can be useful to gain further insights in the value of CCP therapy. In this study, animals were infected with SARS-CoV-2 and the next day, were infused with pooled human convalescent plasma, selected to have a very high titer of neutralizing antibodies. While administration of CCP did not result in a detectable reduction in virus replication in the respiratory tract, it significantly reduced lung inflammation. These data, combined with the results of monoclonal antibody studies, emphasize the need to use products with high titers of neutralizing antibodies, and guide the future development of CCP-based therapies.

immunology↗

bioRxiv2020

Single cell transcriptomic profiling identifies molecular phenotypes of newborn human lung cells

RationaleWhile animal model studies have extensively defined mechanisms controlling cell diversity in the developing mammalian lung, the limited data available from late stage human lung development represents a significant knowledge gap. The NHLBI Molecular Atlas of Lung Development Program (LungMAP) seeks to fill this gap by creating a structural, cellular and molecular atlas of the human and mouse lung. MethodsSingle cell RNA sequencing generated transcriptional profiles of 5500 cells obtained from two one-day old human lungs (born at gestational ages of 39 and 31 weeks) from the LungMAP Human Tissue Core Biorepository at the University of Rochester. Frozen single cell isolates were captured, and library preparation was completed on the Chromium 10X system. Data was analyzed in Seurat, and cellular annotation was performed using the ToppGene functional analysis tool. Single cell sequence data from 32000 postnatal day 1, 3, 7 and 10 mouse lung (n = 2 at each time point) cells generated by the LungMAP Research Center at Cincinnati Childrens Hospital and Medical Center, using Dropseq platform, was integrated with the human data. In situ hybridization was used to confirm the spatial location of cellular phenotypes. ResultsTranscriptional interrogation of donor newborn human lung cells identified distinct clusters representing multiple populations of epithelial, endothelial, fibroblasts, pericytes, smooth muscle, and immune cells and signature genes for each of these populations were identified. Computational integration of newborn human and postnatal mouse lung development cellular transcriptomes facilitated the identification of distinct cellular lineages among all the major cell types. Integration of the human and mouse cellular transcriptomes also demonstrated cell type-specific differences in developmental states of the newborn human lung cells. In particular, matrix fibroblasts could be separated into those representative of younger cells (n=393), or older cells (n=158). This is the first comprehensive molecular map of the cellular landscape of neonatal human lung, including biomarkers for cells at distinct states of development. Our results indicate that integrated single cell RNA profiling of human and mouse lung will help identify common and species-specific mechanisms of lung development and respiratory disease.

genomics↗