bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hypoxia-Inducible Factors (HIF) in CD4+ T cells promote metabolism, switch cytokine secretion, and T cell help in humoral immunity
Authors: Cho Sung Hoon , Raybuck Ariel , Kemboi Edna , Haase Volker , Boothby Mark Robin 
Published: January 2023

Abstract
T cell help in humoral immunity includes interactions of B cells with activated extrafollicular CD4+ and follicular T helper (Tfh) cells. Each can promote antibody responses but Tfh cells play critical roles during germinal center (GC) reactions. After re-stimulation of their antigen receptor (TCR) by B cells, helper T cells act on B cells via CD40 ligand and secreted cytokines that guide immunoglobulin class switching. Recent work showed that hypoxia is a normal feature of most GC, raising questions about molecular mechanisms governing the relationship between hypoxia and T cell help to antibody response. Hypoxia-inducible factors (HIF) are prominent among mechanisms that mediate cellular responses to limited oxygen but also are induced by lymphocyte activation. We now show that loss of HIF-1a and HIF-2a in CD4+ T cells compromised essential functions in help during antibody responses. HIF-1a depletion from CD4 T cells reduced frequencies of antigen-specific GC B cells, Tfh cells, and overall antigen-specific Ab. Compound deficiency of HIF-1a and HIF-2a intensified humoral defects after hapten-carrier immunization. Further, HIF promoted CD40L expression while restraining the FoxP3-positive CD4+ cells in the CCR5+ follicular regulatory (Tfr) population. Glycolysis increases T helper cytokine expression, and HIF was essential for stimulation of glycolysis in T helper cells via TCR or cytokine stimulation, as well as their production of cytokines that direct antibody class switching. Indeed, interferon-g elaboration by HIF-deficient in vivo-generated Tfh cells was impaired. Collectively, the results indicate that HIF transcription factors are vital components of the mechanisms of follicular help during humoral responses.
Transcription coactivator OCA-B mediates interactions between target loci in T cells and is sufficient to promote CD4 memory in vivo
Authors: Tantin Dean R , Zhao Keiji , Williams Matthew A , Hale J Scott , Lai Binbin , Ren Gang , Kim Heejoo 
Published: January 2023

Abstract
Stable epigenetic changes occurring during T cell activation are crucial for the generation of immunological memory. In CD4 T cells, OCA-B (Pou2af1/OBF-1/Bob.1) promotes poised gene expression states in an array of direct immunomodulatory target genes (e.g. Il2, Il21 and Ifng) via the recruitment of the histone lysine demethylase Jmjd1a/Kdm3a. Our prior work indicates that OCA-B is not expressed in naïve CD4 T cells, but becomes stably expressed upon persistent antigen exposure. OCA-B is also critical for the generation of functional CD4 memory T cells in response to pathogen infection. By ectopically expressing OCA-B in SMARTA TCR transgenic T cells and co-transferring transduced T cells together with empty vector controls, we show that OCA-B does not affect primary effector responses, but is sufficient to promote formation of long-lived memory T cells. Although there are no differences in T cell numbers or function, the promotion of memory is preceded in the effector phase by changes in the expression of surface markers such as CD62L, ICOS and PD-1. We identify a mode of transcription regulation by OCA-B in T cells in which OCA-B facilitates communication between target loci such as Il2 and Il21. These results indicate that expressing OCA-B may be useful as a method of enhancing CD4 memory.
The Role of the Innate Immune System in Doxorubicin-Induced Cardiotoxicity
Authors: Bhagat Anchit , Kleinerman Eugenie S 
Published: January 2023

Abstract
Doxorubicin (Dox) is one of the most effective agents for the treatment of pediatric cancers. However, survivors treated with Dox are at high risk for developing cardiovascular disease and succumbing to a cardiac event. Indeed, cardiac failure is the most common cause of non-cancer related deaths. Understanding the mechanisms involved in Dox-induced cardiac failure are necessary to reduce this late effect. Because of the link between inflammation, innate immune cells and other types of cardiomyopathies, we hypothesized that migration & activation of innate immune cells mediated by damaged cardiac fibroblasts may contribute to Dox-induced heart damage, cardiac fibrosis and failure. Mice treated with Dox for 2 weeks showed decreased ejection fraction, increased circulating levels of ROS, and increased infiltration of neutrophils in the heart tissue. Incubation of cardiac fibroblasts with Dox in vitro resulted in the upregulation of inflammatory cytokines (IL-1b, TNFa) and chemokines (MCP-1, CXCL1). Taken together, these data support a role for neutrophils and an innate immune response in Dox-induced cardiotoxicity. Identifying agents that can inhibit or decrease this have the potential to improve cardiac health, QOL and decrease cardiac-related deaths in childhood cancer survivors.
IL-1R signaling enhances neutrophil extracellular traps (NETs) formation and leads to increase lung permeability and hypoxemia in LPS/mechanical ventilation-induced acute lung injury mouse model
Authors: Nosaka Nobuyuki , Martinon Daisy , Crother Timothy R. , Arditi Moshe , Shimada Kenichi 
Published: January 2023

Abstract
Although neutrophils extracellular traps (NETs) play a role in host defense against invading microorganisms, NETs alone play a role in pathogenesis of human acute respiratory distress syndrome (ARDS) either with or without infection. However, the mechanism of NET formation and its functional implications in alveolar space during acute lung injury are not less understood. We created a two-hit lung injury mouse model using intratracheal LPS (0.2 mg/kg), followed by 2.5 hours high-volume mechanical ventilation (30 ml/kg). We observed significant hypoxemia along with increased alveolar leakage, neutrophil infiltration, and NET formation using this model. Neutrophil depletion using (Ly6G[1A8]) monoclonal antibody inhibited these effects. Intriguingly, Il1r1−/− mice were significantly protected from hypoxemia and alveolar leakage despite similar alveolar neutrophil infiltration. We also found that Il1r1−/− mice had reduced levels of cell-free DNA and MPO-DNA complexes in bronchoalveolar lavage fluid (BALF), suggesting that NETs were involved in inducing lung vascular permeability and that IL-1R signaling was involved in inducing NET formation in alveolar space. Inhibition of NET formation via Cl-amidine or removal of NET DNA via DNase I led to reduced hypoxemia and alveolar leakage despite unaltered neutrophil infiltration. Additionally we found that recombinant IL-1β treatment of mouse neutrophils induces NETs, and this was inhibited by IL-1R antagonist (Anakinra). Taken together, we have found that IL-1R signaling-induced NETs play a critical role in development of lung injury, and may offer a new target for therapeutics.
Neuropilin-2 Isoforms Regulate Distinct Functions of Tumor-associated Macrophages in Breast Cancer
Authors: Soloff Adam C , Stanton Rebecca A. , Radio Nicholas M. , Freilino-Glunt Maria , Nasarre Cecile , Dimou Anastasios , Nasarre Patrick , Denlinger Chadrick E. , Oesterreich Steffi , Lee Adrian V. , Lotze Michael T. , Dhupar Rajeev , Gemmill Robert 
Published: January 2023

Abstract

Introduction
Neuropilins are neural guidance molecules which contribute to tissue development. We have shown that the two isoforms of neuropilin-2 endow opposing functionality to tumor cells due to distinct signaling pathways, with Nrp2b promoting metastatic behavior. Due to the role of macrophages (Mθ) in organogenesis and metastasis, we examine the role of Nrp2 isoforms in these cells.

Methods
Stable shRNA knockdown of Nrp2a or Nrp2b in Raw264.7 Mθ were generated. Phagocytosis, cytokine production, and migration were assessed in knockdowns in response to stimuli (TGFβ, HGF, VEGF, IL-10, IFNγ, LPS, β-glucan). Nrp2 isoforms in Mθ from mouse mammary tissue or EO771-induced mammary tumors were measured by FACS and RT-PCR. Mθ were phenotyped via FACS for wound-healing or inflammatory markers. Single-cell (sc)qPCR for a 96 gene panel examining components of signaling pathways, autophagy, metabolism, and pro/anti-tumor responses was performed on 576 CD11b+F4/80+ TAMs FACS-sorted from EO771 tumors.

Results
Nrp2b expression was significantly upregulated in TAMs compared to Mθ of the blood, spleen, or mammary tissues. 56% of the scqPCR transcripts analyzed were significantly altered in Nrp2bHigh vs. Nrp2bLow TAMs, and computation analysis (PCA/tSNE) revealed two distinct TAM subsets enriched for Nrp2b. Nrp2b+ Raw264.7 cells showed decreased ability to phagocytose tumor cells, but increased rates of division and migration in response to growth factors compared to Nrp2a+ counterparts.

Conclusions
We demonstrate, for the first time, that the principle neuropilin-2 isoforms are present in Mθ, regulate unique functionality, and that Nrp2b+ TAMs are both upregulated in mammary tumors and represent a phenotypically unique subtype.
miR-222 stimulates M2b macrophage polarization in severely burned mice through the degradation of long noncoding RNA GAS5
Authors: Ito Ichiaki , Finnerty Celeste C , Herndon David N , Kobayashi Makiko , Suzuki Fujio 
Published: January 2023

Abstract
M2bMφ have been characterized as cells responsible for the increased susceptibility of severely burned mice to various opportunistic infections. We have previously demonstrated that a long noncoding RNA GAS5 is not expressed by M2bMφ, significantly. This RNA is involved in CCL1 gene silencing, and CCL1 is essential for the prolongation of M2bMφ. In this study, the mechanism involved in the reduction of a GAS5 level in M2bMφ was investigated. Mφ were isolated from the mesenteric lymph nodes of mice 1–15 days after severe burn injury (3rd degree, 25% TBSA burn). The level of phosphorylated UPF1 (pUPF1), a marker of the nonsense-mediated RNA decay (NMD) pathway, was determined in various Mφ preparations by Western blotting. In some experiments, these Mφ were transfected with miR-222 mimic, and tested for the GAS5 RNA and CCL1 mRNA levels. miR-222 has been shown to directly binds to GAS5. In the results, the levels of pUPF1 and miR-222 were increased in Mφ from mice 10–15 days after burn injury. These Mφ did not express GAS5 RNA and expressed CCL1 mRNA. The GAS5 reduction was also demonstrated in normal mouse Mφ transfected with miR-222, but not in the same Mφ treated with an inhibitor of the NMD pathway. M2bMφ were not demonstrated in severely burned mice injected with an miR-222 inhibitor. These results suggest that, through the reduction of long noncoding RNA GAS5, miR-222 appeared in Mφ of severely burned mice stimulates the M2bMφ polarization.
Functional characterization of a novel myeloid cell-specific lncRNA U90926
Authors: Sabikunnahar Sabikunnahar , Varnum Stella , Bivona J.J. , Cooper Rachel , Krementsov Dimitry 
Published: January 2023

Abstract
Long non-coding RNAs (lncRNAs) are emerging as novel positive and/or negative regulators of different innate immune cell functions. We previously identified a novel mouse lncRNA of unknown function called U90926, whose expression in activated macrophages was highly dependent on p38 MAP kinase (MAPK). Here, we functionally characterized this gene in myeloid cells. Analysis of U90926 expression revealed no expression across multiple tissues, including unstimulated macrophages. However, toll-like receptor (TLR) stimulation of macrophages rapidly and transiently induced high levels of U90926 expression, which were dependent on p38 MAPK. To study the function of U90926, we generated knockout mice using CRISPR-Cas9, as well as developed RAW 264.7 macrophages knockdown and overexpression using lentivirus-based vectors. We investigated the functional role of U90926 lncRNA using ex vivo activated bone marrow-derived macrophages (BMDMs) and bone marrow-derived dendritic cells (BMDCs). Deletion of U90926 downregulated production of the anti-inflammatory cytokine IL-10 by BMDCs, a cytokine that we and others have shown to be highly dependent on p38 MAPK. In contrast, U90926-deficient BMDC displayed reduced activation-induced expression of MHC class II and CD40, while U90926-deficient BMDM exhibited reduced expression of CD80 and CD86. Taken together, these results identify the lncRNA U90926 as a novel regulator of myeloid cell function and suggest that U90926 may be a positive regulator of IL-10 induction by p38 MAPK, and a negative regulator of the antigen-presentation pathway. Ongoing studies are aimed at identifying the underlying molecular mechanisms and in vivo functions of this gene.
Protective effect of a brown algae, Sargassum horneri on particulate matter-induced oxidative stress and inflammation in MLE-12 cells
Authors: Kim H.J. , Herath K.H.I.N.M. , Kim A. , Mihindukulasooriya S.P. , Ko M. , Jeon Y. , Jee Y. , Kim H.J. 
Published: January 2023

Abstract
The constant exposure to fine particulate matter (PM) induces oxidative stress and proinflammatory cytokine production. The ROS formed by oxidative stress is related to activate NF-κB signal pathway for inflammation. Sargassum horneri, a brown algae found in East Asia, is known to be an excellent source for bioactive components. In this study, the antioxidant and anti-inflammation effects of Sargassum horneri ethanol extract (SHE) on the PM-induced oxidative stress in MLE-12, a type II alveolar epithelial cell line were investigated. As the exposure concentration of PM increased to 1,000 μg/mL, the cell viability was reduced; however, it was increased when treated with SHE. The ROS generation and lipid peroxidation of MLE-12 cells were increased from the PM concentration of 125 μg/mL and they were reduced after treatment of SHE at 62.5 and 125 μg/mL. The expressions of antioxidant enzymes, catalase (CAT) and superoxide dismutase (SOD2), in MLE-12 cells exposed to PM were lower than those exposed to PM with SHE. The PM was proved to increase the expression of 8-OHdG, one of DNA oxidative damage markers, and OGG1, the repair enzyme of 8-OHdG, while SHE protected the DNA damage of cell. The expression of NF-κB signaling was reduced by SHE. These results suggest that SHE can adjust the expression of antioxidant enzymes, help to suppress the oxidative stress induced by PM, and attenuate its oxidative damage and NF-κB pathway to lung epithelial cells by eliminating over-produced ROS.
This research is part of a project titled ‘Development of functional food products with natural materials derived from marine resources’ funded by the Ministry of Oceans and Fisheries, Republic of Korea in 2017 (Project NO. 20172085).
MALAT1 is essential for A-NHEJ pathway choice during B cell immunoglobulin class switch recombination
Authors: Zhao Jianjun , Hu Yi , Lin Jianhong 
Published: January 2023

Abstract
Metastasis-associated lung adenocarcinoma transcript 1(MALAT1) has been found high expressed in multiple cancer type including B cell lymphoma and multiple myeloma. In human cancer murine models, deficiency of MALAT1 reduce the tumor burden and malignancy phynotype. We have identified MALAT1 in alternative-non-homozygous end joining(A-NHEJ) pathway by binding to PARP1 and LIG3 in multiple myeloma cells, two key components of the A-NHEJ protein complex. To investigate requirments for MALAT1 in A-NHEJ pathway, by using MALAT1 deficient mice, we found that the contribution of MALAT1 in the context of AID induced DNA breaks in CSR of B cells in mice. MALAT1 is required for A-NHEJ DNA repair pathway, but not the NHEJ pathway, which is the major DNA repair pathway for CSR. To further prove the hypothesis that MALAT1 promote A-NHEJ pathway in B cells, we have engineered mice that conditionally overexpress MALAT1 in B lymphocytes confers a strong A-NHEJ activity in CSR. More importantly, we also found IgH/c-myc translocations are promoted in MALAT1 B cell specific transgenic mice. Thus, we identified MALAT1 as a critical noncoding RNA in regulating A-NHEJ pathway during CSR.
IL-21-dependent Tbet+ B cells require Bcl6 and receive delayed help from non-Tfh T cells
Authors: Levack Russell C , Popescu Maria , Winslow Gary 
Published: January 2023

Abstract
Tbet+ B cells are a novel lymphocyte population that have been implicated in a multitude of diseases and infections, including hepatitis, AIDs, malaria, SLE, and age-related autoimmunity. Our laboratory has characterized a population of Tbet+ CD11c+ memory B cells that arise during Ehrlichia muris infection in mice, and we have used this infection model to study the ontogeny of these cells. We have previously demonstrated that the generation of Tbet+ memory B cells requires CD4 T cells and IL-21 signaling, implicating a role for Tfh cells in Tbet+ B cell development. However, Tfh cells were not required for the generation of Tbet+ memory B cells. Rather, these data suggest that Tbet+ B cells received help from a population of non-Tfh CD4 T cells capable of secreting IL-21, likely Th1 cells. As expected, the helper CD4 T cells provided CD40:CD40L signals to the Tbet+ B cells; however, these interactions occurred 16 days or later post-infection. While the helper CD4 T cells did not require Bcl6, the same was not true for the Tbet+ B cells, as Tbet+ memory B cells were not generated in the absence of B cell-intrinsic Bcl6. These data suggest that T-bet B cells require a novel transcriptional program whereby Tbet and Bcl6 function cooperatively, perhaps transiently. Collectively, these data support a model whereby a subset of non-Tfh T cells (likely Th1 cells) provide CD40 and IL-21 signals that drive the formation of Bcl6-dependent Tbet+ B cells.
Long-lived effector CD8+ T cells are transcriptionally and functionally distinct from effector memory cells
Authors: Nguyen Hong , Toma Clara , Omilusik Kyla , Goldrath Ananda W. , Milner J. Justin 
Published: January 2023

Abstract
In response to an infection or vaccination, antigen-specific CD8+ T cells have the capacity to differentiate into long-lived memory T cells that ultimately confer critical protection against re-infection. The memory CD8+ T cell population is heterogeneous and comprised of circulating effector memory (Tem) and central memory (Tcm) cells as well as non-circulating memory cells or tissue-resident memory cells (Trm). Each memory T cell subset is characterized by distinct phenotypic and functional attributes as well as localization patterns. It has previously been demonstrated that circulating memory subsets can be further subdivided based on effector function or migration patterns. Here, we contribute to the clarification of this heterogeneity by characterizing the gene expression, functional activity and differentiation requirements of long-lived CD127loCD62Llo effector cells (LLE) that can persist at least one year after infection in mice. LLE were found to be phenotypically and functionally distinct from CD127hiCD62Llo Tem and CD127hiCD62LhiTcm subsets. LLE exhibited a unique transcriptional profile, with genes expressed in common with both CD127loKLRG1hi short-lived effector cells and Tem. Further, we refine roles for key fate-specifying transcription factors in controlling the differentiation of LLE versus Tem subsets. These studies further highlight the extent of memory T cell heterogeneity and may inform novel vaccination strategies.
Distinct lymph node entry efficiencies for CD8+ and CD4+ T cells are eliminated during malnourishment
Authors: Gubbels Bupp Melanie R , Goulmamine Syreen , Gibson David , Little Amie , Murphy Sarah , Patrick Kristin , Thoner Tim 
Published: January 2023

Abstract
Previous work has suggested that glucocorticoids upregulate expression of the IL-7 receptor component, CD127 on peripheral T cells, even though the total number of peripheral T cells declines dramatically during malnourishment. We have proposed that CD127 up-regulation contributes to peripheral T cell diminishment by increasing the scavenge rate of IL-7 and thereby providing a mechanism to rapidly adjust the total number of T cells during malnutrition. As such, each malnourished T cell would receive a higher dose of IL-7 than control T cells. We next wondered if increased exposure to IL-7 during malnourishment might confer additional energy-saving behaviors. Thus, we compared lymph node entry rates of adoptively-transferred malnourished and control T cells in malnourished and control recipients. As expected, control CD4+ T cells were more efficient than control CD8+ T cells at entering the lymph nodes. Interestingly, regardless of recipient diet, malnourished CD4+ and CD8+T cells entered the lymph nodes at equivalent rates. The molecular events that enable faster CD4+ T cell entry into lymph nodes in control mice is currently unknown. An improved understanding of T cell-intrinsic changes that occur during malnourishment should enhance our knowledge of CD4+ and CD8+ T cell migration, as well as uncover strategies to improve vaccination responses in malnourished children.
PRMT5-mediated arginine methylation controls the strength of signaling via γc-family cytokines required for T cell maintenance
Authors: Inoue Maia , Okamoto Kazuo , Takayanagi Hiroshi 
Published: January 2023

Abstract
Protein arginine methylation is a post-translational modification which is involved in a wide range of biological processes such as transcriptional control and pre-mRNA splicing. Various cytokines, including IL-2 and IL-7, play crucial roles in T cell development and activation. These cytokines utilize the common cytokine receptor γ-chain (γc, encoded by Il2rg) and its associated kinase JAK3 for signal transduction, but the regulatory mechanism underlying γc and JAK3 expression remains to be elucidated. Here we show that protein arginine methyltransferase 5 (PRMT5) has a pivotal role in the maintenance of invariant NKT (iNKT), CD4+T and CD8+T cells. T-cell specific deletion of the Prmt5 gene resulted in a severe loss of iNKT cells as well as a decreased number of CD4+T and CD8+T cells. PRMT5-mediated arginine methylation is essential for the expression of γc and JAK3 required for iNKT cell development and the proliferation and survival of peripheral T cells. PRMT5 stimulates the symmetric dimethylation of the Sm proteins that facilitates the splicing of the Il2rg and Jak3 premRNA in T cells. Taken together, our findings show that PRMT5-mediated arginine methylation is a crucial determinant of the strength of signaling via γc-family cytokines and T cell maintenance.
NFAT1 and NFAT2 differentially regulate CTL differentiation upon acute viral infection
Authors: Xu Tianhao , Keller Ashleigh , Martinez Gustavo J 
Published: January 2023

Abstract
CD8+ T cell differentiation orchestrated by transcription regulators is critical for balancing pathogen eradication and long-term immunity by effector and memory CTLs respectively. The transcription factor Nuclear Factor of Activated T cells (NFAT) family members are known for their roles in T cell development and activation but still largely undetermined in CD8+ T cell differentiation in vivo. Here, we interrogated the role of two NFAT family members, NFAT1 and NFAT2, in the effector and memory phase of CD8+ T cell differentiation using LCMVArm acute infection model. We found that NFAT1 is critical for effector population generation whereas NFAT2 is required for promoting memory CTLs in a cell-intrinsic manner. Moreover, we found that mice lacking both NFAT1 and NFAT2 in T cells display a significant increase in KLRG1hi and CD127hi population and are unable to clear an acute viral infection. NFAT-deficient CTLs showed different degrees of impaired IFN-g and TNF-a expression with NFAT1 being mainly responsible for IFN-g production as well as for antigen-specific cytotoxicity. To further comprehend the molecular mechanisms behind this differential CTL commitment upon deficiency of NFAT members, we performed RNA-seq analysis. Our results have identified genes uniquely regulated by NFAT1 or NFAT2, and we are in the process of further understanding how this differential transcriptome translates into the observed distinct CTL differentiation. Overall, our results suggest that NFAT1 and NFAT2 have distinct roles in mediating CD8+ T cell differentiation and function.