bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identifying and targeting a subpopulation of dendritic cells with enhanced activation of adaptive responses - identifying first responders
Authors: Esser-Kahn Aaron P , Ung Trevor Wai-Ming 
Published: August 2023

Abstract
Dendritic cell (DC) activation via pathogen-associated molecular patterns (PAMPs) is critical for antigen presentation and development of adaptive immune responses, but the stochastic distribution of DC responses to PAMP signaling, especially during the initial stages of immune activation, is poorly understood. In this study, we isolate a unique DC subpopulation via preferential phagocytosis of microparticles (MPs) and characterize this subpopulation of “first responders” (FRs). We present results that show these cells (1) can be isolated and studied via both increased accumulation of the micron-sized particles and combinations of cell surface markers, (2) show increased responses to PAMPs, (3) facilitate adaptive immune responses by providing the initial paracrine signaling, and (4) can be selectively targeted by vaccines to modulate both antibody and T cell responses in vivo. This study presents insights into a temporally controlled, distinctive cell population that influences downstream immune responses. Furthermore, it demonstrates potential for improving vaccine designs via FR targeting.
7U01AI124286-03, 5 F32 AI147517
NF-κB activation and pro-inflammatory cytokine production is modulated by a single point-mutation in the RSV fusion protein
Authors: Santhin Austin Bruce , Waldstein Kody , Varga Steven M 
Published: August 2023

Abstract
Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in young children worldwide. Clinical studies have associated elevated levels of pro-inflammatory cytokines with severe RSV-induced disease. However, the viral mechanisms that control disease severity remain undefined. Infection with the RSV 2–20 strain resulted in increased IL-1β, IL-6, and TNF levels compared to infection with RSV A2. RSV 2–20 also induced significantly increased NF-κB activation 6hr and 12hr post-infection as compared to RSV A2. A recombinant A2 virus expressing the 2–20 fusion (F) protein induced pro-inflammatory cytokines and NF-κB activation to similar levels as wild-type 2–20. Specific amino acids in a region of the RSV F protein likely to interact with host cells contributed to these strain-dependent differences. A single point-mutation at amino acid position 63 of the RSV F protein significantly affected IL-1β, IL-6, and TNF cytokine levels as well as NF-κB activation. Our results demonstrate that the amino acid position 63 in the RSV F protein plays a critical role in the induction of pro-inflammatory cytokines and modulating disease severity in the animal model and may contribute to differential RSV pathogenesis.
Supported by grants from NIH NIAID (RO1) and the University of Iowa Immunology T32 training grant.
Defining parameters that influence susceptibility and protection to murine respiratory beta-coronavirus MHV-1 infection
Authors: Silva Elvia E , Moioffer Steven , Van De Wall Stephanie , Berton Roger , Meyerholz David , Harty John T , Badovinac Vladimir 
Published: August 2023

Abstract
Patients infected with SARS-CoV-2 can experience variable susceptibility and sepsis-like immune dysfunction. Also, patients with comorbidities such as previous septic events are more likely to be hospitalized and succumb to COVID19 complications. However, the extent to which respiratory beta-coronavirus pathology is dose dependent and produces sepsis-like dysregulation in an experimental murine model are not completely defined. We utilized an established SARS-like murine model by infecting Murine Hepatitis Virus 1 (MHV-1) susceptible C3H/HeJ mice intranasally and analyzed responses over time after primary and/or secondary challenges. Immunologically naïve C3H mice undergo pathological changes defined by dose-dependent changes in disease severity and lung infiltrate/edema. MHV-infected mice also experience sepsis-like lymphopenia and cytokine dysregulation in the blood. Importantly, a low/surviving dose (5×102 PFU) was identified that yielded no morbidity/mortality after infection of C3H hosts. However, this low dose provides antibody dependent but not CD4/CD8 circulatory T cell dependent protection against a lethal high dose MHV-1 re-challenge. In addition, while C3H hosts with history of prior infections were more resistant, C3H mice that survived surgical sepsis showed increased susceptibility to MHV-1 infection over their surgical sham controls. Together, these data define how infection dose, immunological status, and/or comorbidities influence outcome of primary and secondary beta-coronavirus infections in highly susceptible hosts.
Supported by grants from NIH (R35GM134880, T32AI007511)
STINGing CD4+ T cells to induce refractoriness to HIV infection
Authors: Tomalka Jeffrey Alan , Sadek Naseem , Welbourn Sarah , Gordon David , Sekaly Rafick-Pierre 
Published: August 2023

Abstract
HIV rapidly infects CD4+ T cells where it can establish latent infection. Identifying immune mechanisms which can render CD4+ T cells refractory to infection represents a critical step in limiting infection and viral spread. Using purified memory CD4+ T cells from healthy donors, we found that activation of the STING signaling pathway with 0.5 mM of the STING agonist diABZI was sufficient to induce a state of refractoriness to in vitro HIV infection in memory CD4+ T cells, a major source of the HIV reservoir. We observed that STING activation in CD4+ T cells induces Type I IFN production and activates p-IRF3. CRISPR KD of STING in memory CD4+ T cells led to a significant increase in HIV infection, demonstrating a cell intrinsic role for STING signaling in limiting HIV infection/replication. Using proteomics, we identified that diABZI significantly and potently induces restriction factors and proteins involved in antiviral immunity and Type 1 IFN signaling. Importantly, proteins that were significantly reduced mapped to pathways including RNA processing and protein translation which are aspects of the host machinery which HIV needs to co-opt to replicate and produce infectious virions. Our data provide mechanistic insight into the STING pathway as a means to render CD4+ T cells refractory to HIV infection and highlights that this pathway lands a “1–2” punch by increasing expression of antiviral proteins that directly target the virus while suppressing the cellular machinery needed for the viral life cycle. The potential to use a STING agonist as a post-exposure therapeutic which directly limits viral infection while promoting global antiviral immunity represents a novel strategy that may stop HIV infection in its tracks.
CD127 and Sca1 mark self-driven memory-phenotype CD4+ T cells that differ from foreign antigen-specific memory cells and possess inflammatogenic and anti-tumor activities
Authors: Kawabe Takeshi , Ciucci Thomas , Kim Kwang Soon , Yang Ziying , Kawajiri Akihisa , Tayama Shunichi , Ishii Naoto , Jankovic Dragana , Zhu Jinfang , Sprent Jonathan , Bosselut Remy , Sher Alan 
Published: August 2023

Abstract
Under steady-state conditions, conventional CD4+ T lymphocytes are divided into naïve (CD44lo CD62Lhi) and memory (CD44hi CD62Llo) cell compartments. While the latter population is presumed to comprise a mixture of explicit foreign antigen (Ag)-specific “authentic” memory and foreign Ag-independent memory-phenotype (MP) cells, phenotypic markers differentially expressed in these two cell types have yet to be identified. Moreover, it is unknown whether MP cells consist of distinct subsets defined by marker expression. In this study we demonstrate using combined single cell RNA sequencing and flow cytometric approaches that self-driven MP CD4+ T lymphocytes are divided into CD127hi Sca1lo, CD127hi Sca1hi, CD127lo Sca1hi, and CD127lo Sca1lo subpopulations that are Bcl2lo while foreign Ag-specific memory cells are CD127hi Sca1hi Bcl2hi. We further show that amongst the four MP subsets, CD127hi Sca1hi lymphocytes represent the most quiescent, cell division-experienced subpopulation derived from peripheral naïve precursors. Finally, we provide new evidence arguing that the CD127hi Sca1hi MP subpopulation tonically expresses T-bet and possesses the capacity to trigger systemic inflammation including colitis, interstitial pneumonia, and nephritis as well as to exert anti-tumor activity against malignant lymphoma. Together our findings define MP CD4+ T lymphocytes as a unique, self-driven population consisting of distinct subsets that differ from conventional foreign Ag-specific memory cells in marker expression and reveal the inflammatogenic nature of the mature CD127hi Sca1hi MP cells.
HnRNPL is essential for T cell function in the Periphery
Authors: White Tristan L , Jin Ye , Morel Penelope A 
Published: August 2023

Abstract
While RNA binding proteins (RBPs) have recently emerged as regulators of gene expression in immune cells, their effect on T cell fate needs further investigation. Heterogeneous Nuclear Ribonucleoprotein (hnRNPs) are RBPs that play a crucial role in many aspects of RNA biogenesis, alternative splicing, expression, and function. During T cell development hnRNPL is known to regulate the proliferation, and migration of thymic pre-T cells, as loss of hnRNPL in early T cell development results in a failure of T cells to reach the periphery. Little is known about how hnRNPL affects T cell activation, and function. Our lab has used CD4 Cre × hnRNPLFl/Fl (KO) mice to understand the role of hnRNPL in peripheral T cells. Our initial study of the steady state profile of the KO mice shows normal migration of T cells form the thymus, but there is a reduction in peripheral T cell numbers. We also show that hnRNPL plays an important role in T cell activation and survival, since T cells lacking hnRNPL do not survive long enough to differentiate into T helper cell subsets. In vivo, using immunization studies, we show that KO CD4 T cells fail to fully differentiate into Tfh and are unable to support the formation of germinal center B cells. To ensure the effect that hnRNPL has on T cells in the periphery is not caused by the loss of hnRNPL during thymic T cell development we are using the CD4-Cre/ERT2 × hnRNPL (I-KO) to investigate how the loss of hnRNPL in peripheral T cell affects the ability of T cells to differentiate and survive post activation. Further studies will also focus on the mechanisms hnRNPL use to regulate T cells activation and survival. These studies suggest that hnRNPL plays an important role in the activation and survival of peripheral T cells.
AAI Fellowship
Single-cell Spatial Phenotyping of Immune and Metabolic Landscapes in Systemic Lupus Erythematosus
Authors: Jhaveri Niyati , Klymyshyn Dmytro , Ben Cheikh Bassem , Pratapa Aditya , Braubach Oliver 
Published: August 2023

Abstract
Autoimmune diseases like systemic lupus erythematosus (SLE) affect the health of multiple organ systems including the central nervous system, skin, joints, and kidneys. The heterogeneity of clinical profiles observed with SLE reflects a complex dysregulation of cellular processes, including metabolism, apoptotic clearance, and inflammation. Diagnosis and treatment of SLE is thus challenging, and few new treatments have been approved over the past 60 years. In this study, we aimed to characterize the spatial immune and metabolic profiles of SLE at single cell resolution. To do so, we profiled a cohort of human FFPE SLE tissues with an ultrahigh-plex panel of &gt;50 oligo-conjugated antibodies representing immune, apoptotic, metabolic and stress markers. Whole-slide, spatial phenotyping was performed using the PhenoCycler®-Fusion system, followed by deep bioinformatic analyses to determine the cellular phenotypes, spatial neighborhoods, and metabolic determinants of SLE. By combining immune cell lineage information with expression of key proteins involved in glycolysis, amino acid metabolism, lipid metabolism, hypoxia, oxidative stress, and apoptosis, we elucidated the functional dysregulation in key immune subsystems that may contribute to development of autoimmunity and inflammation associated with SLE. Spatial phenotyping also revealed a high degree of inter- and intra-sample heterogeneity, confirming the complexity of the SLE clinical profile. Collectively, our data amount to new insights into metabolic reprogramming of immune cells in autoimmune diseases and may aid in the identification of novel therapeutic biomarkers within the tissue microenvironment of SLE patients.
The adaptation model of immunity: signal IV matters most in determining the functional outcomes of immune responses
Authors: Manjili Masoud H 
Published: August 2023

Abstract
Current research in immunology and immunotherapy is fully influenced by the self-nonself (SNS) model of immunity. This theoretical model suggests that alloreactivity results in graft rejection whereas tolerance towards self-antigens expressed by malignant cells facilitates cancer development. Similarly, breakage of immunological tolerance towards self-antigens results in autoimmune diseases. Accordingly, immune suppression is recommended for the management of autoimmune diseases, allergy, and organ transplantation while immune inducers are used for the treatment of cancers. Nevertheless, a cure for these human diseases remains elusive. This is in large part due to the application of the SNS model in the areas that are beyond its realm. The SNS model is designed to explain how an immune response is induced rather than to predict whether an immune response succeeds or fails against its target. Here, I propose the adaptation model of immunity to explain the decision-making process by activated T cells. According to this model, all somatic cells express adaptation receptors (AdRs) that relay survival signals upon engagement with their nominal adaptation ligands (AdLs) expressed on activated T cells. The AdR/AdL axis establishes signal IV to support immune-mediated tissue homeostasis. Any loss or alterations in the expression of tissue-specific AdRs results in immune intolerance or autoimmune diseases as well as graft rejection. Upregulation or downregulation of the AdRs by tumor cells could also dictate the outcomes of tumor-reactive immune responses. Therefore, novel therapeutics should focus on the discovery and targeting of the AdRs for the treatment of immune-related diseases and cancer.
This work was supported by the Office of the Assistant Secretary of Defense for Health Affairs through the Breast Cancer Research Program under Award No. W81XWH2210793. Opinions, interpretations, conclusions, and recommendations are those of the authors and are not necessarily endorsed by the U.S. Department of Defense.. This work was also supported by multi-investigator pilot funding from the VCU Massey Cancer Centre, supported in part with funding from NIH/NCI Cancer Centre support grants P30 CA016059.
Type I Interferon-Dependent and -Independent TRIF Signaling are Required for Autoantibody Generation in an Induced Model of Systemic Lupus Erythematosus
Authors: Pilon Celeste , Subang Rebecca , Lonina Elena , Lesage Sylvie , Qureshi Salman T , Charette Emilie , Fonseca Gregory , Levine Jerrold S , Rauch Joyce 
Published: August 2023

Abstract
Systemic lupus erythematosus (SLE) is an autoimmune condition characterized by the production of autoantibodies to cellular and nuclear self-antigens, with damage to multiple organs. Immunization with the SLE autoantigen β2-glycoprotein I (β2GPI) and TLR4 ligand lipopolysaccharide (LPS) induces a murine model of SLE characterized by the generation of autoantibodies to multiple SLE antigens. LPS induces both inflammatory cytokines and type I interferons (IFNs) by signaling through the adaptor proteins MyD88 and TRIF, respectively. We investigated the mechanisms of LPS-dependent signaling on the induction of murine SLE following β2GPI/LPS immunization. Immunization of mice deficient in MyD88 or TRIF with β2GPI/LPS revealed that LPS-dependent TRIF signaling preferentially promoted autoantibody production in this model, compared to MyD88 signaling. Furthermore, SLE-specific autoantibody production was induced by TLR3 or TLR4 agonists, in combination with β2GPI, but not by agonists of TRIF-independent TLRs. RNA-sequencing of dendritic cells and macrophages isolated from wildtype (WT) and TRIF-deficient mice immunized with β2GPI/LPS revealed differential expression of both type I IFN-dependent and -independent genes. Moreover, type I IFN receptor (IFNaR)-deficient mice immunized with β2GPI/LPS showed diminished autoantibody production compared to WT mice, but to a lesser extent than TRIF-deficient mice. We conclude that LPS-dependent TRIF signaling is required for the generation of autoantibody production in our induced SLE model, both through type I IFN-dependent and - independent effects.
Supported by grants from CIHR (????)
Th17 cells of type 2 diabetic patients present an aberrant fatty acid metabolic pathway
Authors: Ujagar Naveena , Sriram Trupti , Chan Dennis , Proctor Elizabeth , Nicholas Dequina 
Published: August 2023

Abstract
Approximately 90% of the 537 million diabetic adults worldwide are living with type 2 diabetes (T2D). T2D is a metabolic disorder characterized by elevated blood glucose, which develops when a person is resistant to or cannot make enough insulin. Chronic systemic inflammation is a key contributing factor in the onset of insulin resistance and T2D. This inflammation in T2D patients stems from T-helper 17 (Th17) cells, likely due to defects in fatty acid metabolic pathways driving Th17 inflammation in T2D. While the importance of lipid metabolism has been shown in in vitro differentiated Th17 cells, the metabolism of endogenous Th17 cells in health or T2D has not been characterized due to their low abundance in vivo. We overcame this obstacle and established the relationship between defects in fatty acid metabolism and endogenous Th17 effector function with a novel Th17 cell enrichment assay. We captured CD4+ T cells with a hydrogel particle and magnetically purified them based on secretion of IL-17A/17F/21, allowing for us to perform scRNAseq on endogenous, activated Th17 cells. We then utilized an algorithm named Compass-powered by scRNAseq data and flux balance analysis, to characterize the cellular metabolic state of our captured Th17 cells. By overlaying scRNAseq data from endogenous Th17 cells of diabetic and control patients with gene ontology resources and applying in-silico modeling of metabolic pathways, we identified key lipid pathways driving Th17 inflammation in T2D and conducted the first study ever to be done on endogenous Th17 cells of healthy and T2D patients. This novel approach, and the data that ensued from it, with functional validation will illuminate inflammatory markers to target for creation of an immunotherapy for T2D.
Supported by grants from NIH (1DP2AI171121-01)
Ackr1-deficient mice are protected from lethal SARS-CoV-2 challenge
Authors: Majumdar Shamik , Pontejo Sergio M , Weaver Joseph , Murphy Philip M 
Published: August 2023

Abstract
To date, there have been more than 613 million confirmed cases of COVID-19, with over 6 million deaths worldwide. In severe cases, the causative agent of the COVID-19, SARS-CoV-2, induces acute respiratory distress syndrome. To study the roles of chemokine pathways during COVID-19 pathogenesis, we performed an infection screen in mice deficient in chemokine ligands and receptors using the mouse-adapted strain of the virus. Weight loss and death were recorded for 2 weeks after infection of wild type mice, and mice genetically deficient for Ccr2, Ccr5, Ccr6, Cxcr3, Cxcr6, Cxcl10 or the atypical chemokine receptor Ackr1. Acute weight loss was observed in all infected mouse strains; however, Ackr1−/− mice uniquely displayed markedly increased survival compared to wild type mice. ACKR1 (also known as the Duffy antigen receptor for chemokines) is a non-signaling receptor expressed on endothelial cells, erythrocytes and a subset of neurons that binds to a wide range of chemokines thereby controlling their availability as a scavenger and shaping chemotactic gradients. Comprehensive expression analysis revealed Ackr1 as the most highly induced chemokine receptor in infected lung post-infection. Of note, COVID-19 mortality is disproportionately low in West Africa, overlapping with the geographic distribution of genetic deficiency of erythrocyte ACKR1 due to a single nucleotide polymorphism in the ACKR1 promoter that interrupts binding of GATA-1. Further studies are required to understand the modulation of SARS-CoV-2 pathogenesis by Ackr1 and its potential to explain the trajectory and limited mortality of Covid-19 in Africa and to serve as a potential therapeutic target.
Host Gut-Resistome and Gut-Immune Axes are the key to Non-cholera Vibrio infection severity in aging and heat stress
Authors: Roy Subhajit , Saha Punnag , Bose Dipro , Chatterjee Saurabh 
Published: August 2023

Abstract
Global incidences of periodic heat waves and exposures are on the rise and that also have impacted non-cholera Vibrio abundance in coastal waters. We hypothesized that aging and a parallel heat stress (HS) may potentiate the risk of non-cholera Vibrio infections in the host and exacerbate the pathology. To study the underlying pathological changes in possible co-exposure of HS and subsequent non-cholera Vibrio challenge, an aging mouse model was used. Mice were exposed to HS at 40°C for three hours/day for 15 days. This was followed by a Vibrio vulnificus challenge 24 hours post HS exposure. Results showed that HS exposure decreased the diversity of the host gut microbiome and altered the relative abundance of many important taxa as assessed by Whole Meta-Genome Sequencing (WMS). Gut leaching was evident via the alteration of tight junction proteins and concomitant endotoxemia was evident. Decrease in abundance of Akkermansia muciniphila, a species well known for protection of gut barrier integrity was observed. Serum CRP levels, a clinical indicator of septicemia was elevated in the HS mice following Vibrio vulnificus infection, over and above the Vibrio-only or HS-only group. Significant amplification of gut leaching, gastrointestinal and systemic inflammation (IL-1β, IL-6, TNF-α), T-cell senescence and altering IgA levels were also noted in the HS+ Vibrio group. WMS also showed an altered host resistome signature and abundance of genes harboring the antimicrobial resistance to tetracycline group of antibiotics, a common antibiotic used for treatment of non-cholera Vibrio infections. In summary, HS augmented susceptibility to non-cholera vibriosis via host variability in resistome patterns and altered gut-immune mediators.
This study was supported by NIH/NIEHS Grant 1P01ES028942-01#Project 4 Toxicology awarded to Dr. S. Chatterjee.