bluuebunny/crossref_metadata_2025_split huggingface dataset:
A mechanism for the elimination of IgE plasma cells
Authors: Wade-Vallance Adam Kevin , Yang Zhiyong , Libang Jeremy B , Robinson Marcus J , Tarlinton David M , Allen Christopher D C 
Published: August 2023

Abstract
The proper regulation of IgE production safeguards against allergic disease, highlighting the importance of mechanisms that restrict IgE plasma cell (PC) survival. IgE PCs have unusually high surface B cell receptor (BCR) expression, yet the functional consequences of ligating this receptor are unknown. Here, we found that BCR ligation induced BCR signaling in IgE PCs followed by their elimination. In cell culture, exposure of IgE PCs to cognate antigen or anti-BCR antibodies induced apoptosis. IgE PC depletion correlated with the affinity, avidity, amount, and duration of antigen exposure and required the BCR signalosome components Syk, BLNK, and PLCγ2. In mice with a PC-specific impairment of BCR signaling, the abundance of IgE PCs was selectively increased. Conversely, BCR ligation by injection of cognate antigen or anti-IgE depleted IgE PCs. These findings establish a mechanism for the elimination of IgE PCs through BCR ligation. This has important implications for allergen tolerance and immunotherapy as well as anti-IgE monoclonal antibody treatments.
This research was supported by the National Institute of Allergy and Infections Diseases of the National Institutes of Health under Award Number R01AI130470; the Program for Breakthrough Biomedical Research, which is partially funded by the Sandler Foundation; the Sandler Asthma Basic Research Center; and the Cardiovascular Research Institute at the University of California, San Francisco. C.D.C.A. was a Pew Scholar in the Biomedical Sciences, supported by The Pew Charitable Trusts. A.K.W-V was supported by a Doctoral Foreign Study Award from the Canadian Institute of Health Research, funding reference number DFD-170769. D.M.T. and M.J.R. were funded by National Health and Medical Research Council (NHMRC) Australia by an Investigator Award (APP1175411) and Ideas Grant (APP1185294), respectively. The content is solely the responsibility of the authors and does not necessarily represent the official views of the funding agencies.
Histamine 3 receptor antagonism mitigates neuroinflammation and depression-like behavior in a mouse model of food allergy
Authors: La Mae Germundson-Hermanson Danielle , Nagamoto-Combs Kumi 
Published: August 2023

Abstract
Histamine (HA) is a major allergic response mediator as well as a neuromodulatory neurotransmitter and a blood-brain barrier (BBB) regulator. Consequently, dysregulation of the central histaminergic system could offset brain homeostasis and function. Indeed, mood and behavioral disorders are often comorbid with conditions that elevate systemic HA, such as mastocytosis and allergy. We have previously shown elevated levels of brain HA and its receptor subtype H3 (H3R) in a mouse model of cow’s milk allergy (CMA). Additionally, neuroinflammation and cortical demyelination were observed in association with depression-like behavior in CMA mice. However, whether the elevated HA and H3R were responsible for the development of these cellular and behavioral pathologies is unknown. We hypothesized that the elevated brain HA leads to central histaminergic dysfunction through H3R, ultimately resulting in cortical demyelination and aberrant behaviors. To investigate the role of H3R, CMA mice were treated daily with thioperamide, a selective BBB-permeable H3R antagonist, to block the action of HA through this receptor. Despite the production of allergen-specific IgE, thioperamide prevented depression-like behavior. Thioperamide also ameliorated CMA-associated cortical demyelination and axonal loss compared to saline-treated mice. Our findings strongly suggested that H3R signaling contributed to cortical demyelination and the development of depression-like behaviors in our CMA mice. Targeting HA production or signaling may provide a therapeutic strategy to reduce the risk of neurodegeneration and associated brain dysfunction in susceptible individuals.
Supported by grants from NIH (1R01AI168563-01, P20GM113123-06, and P20GM103442).
Identification of BST2 as a biomarker for alopecia areata in both mice and humans
Authors: Velasquez Cristina , Coast Jake 
Published: August 2023

Abstract
Alopecia areata is an autoimmune disease characterized by aberrant non-scarring hair loss. 147 million people worldwide are currently diagnosed with alopecia areata with a lifetime incidence of 2.1%. The hair follicle is a site of immune privilege however in alopecia areata, CD4+ helper T cells and CD8+ cytotoxic T cells infiltrate and attack the hair follicle. To better understand the initiating mechanisms surrounding alopecia areata, we examined the function of epidermal γδ T cells and dermal macrophages in the initiation of or protection from the disease. We show that epidermal γδ T cells and keratinocytes are elevated in the skin of C3H/HeJ mice with alopecia areata. Analysis of publicly available single cell RNA sequencing data delineated the top differentially expressed genes of epidermal γδ T cells and dermal macrophages. Bone marrow stromal antigen 2 (BST2) is significantly upregulated among both cell types and is a novel gene associated with alopecia areata. Using immunofluorescence microscopy we determined that a small population of hair follicle-associated epidermal γδ T cells express BST2 in C3H/HeJ mice and C57Bl/6J mice without alopecia areata. We have also identified a significant increase in BST2 expression in skin sections from mice affected by alopecia areata. BST2+CD11b+ macrophages upregulate genes associated with antiviral activity indicating an association between the pathogenesis of alopecia areata and infectious viral particles. BST2+ epidermal γδ T cells upregulate genes associated with FAK signaling in alopecia areata, which indicates a role for FAK in the increased number of epidermal T cells. These studies identify a role for BST2 in alopecia areata that is mediated by epidermal γδ T cells and macrophages.
Anti-PD-1 antibodies recognizing the membrane-proximal region are agonists that can stimulate immunosuppressive activity of PD-1
Authors: Ohta Akio , Suzuki Kensuke , Tajima Masaki , Tokumaru Yosuke , Oshiro Yuya , Nagata Satoshi , Kamada Haruhiko , Kihara Miho , Nakano Kohei , Honjo Tasuku 
Published: August 2023

Abstract
The success of immunoenhancing anti-PD-1 blocking antibodies in cancer treatment indicates the biological significance of PD-1-dependent immunoregulation in the human immune system. Active stimulation of PD-1 is potentially an effective approach in treating various inflammatory disorders; however, agonistic anti-PD-1 antibodies stimulating the immunosuppressive activity are not clearly defined. Here, by assessing the biological activities of anti-human PD-1 mAbs, we have identified functional anti-PD-1 agonists in the antibody group recognizing the membrane-proximal extracellular region (MPER). MPER recognition was characteristic to anti-PD-1 agonist mAbs and distinct from blocking mAbs binding to the membrane-distal region of PD-1. The agonistic activity was mediated by Fc receptor-dependent co-ligation of PD-1 molecules. In vivo anti-inflammatory efficacy of the PD-1 agonist in murine disease models suggests its clinical potential to various inflammatory disorders including autoimmune diseases.
Meiji Seika Pharma, Co., Ltd. Foundation for Biomedical Research and Innovation at Kobe
Evidence for intrathymic and neuroimmune alterations in a mouse model of neglect-related early life stressors
Authors: Choe Jamie Y , Donkor Michael , Vann Philip , Sumien Nathalie , Thorpe Roland J , Jones Harlan P 
Published: August 2023

Abstract
Environmental exposures during the impressionable early life period can influence biological and behavioral development. These exposures accumulate from birth and comprise the exposome, which impacts health and disease. Neglect is a major source of early life stress (ELS) and accounts for 80% of reported child abuse in the United States. Forms of neglect vary (e.g., physical, medical, emotional, nutritional) and with increased concerns for abuse during the COVID-19 pandemic, we require a deeper understanding of how ELS affects immune system programming/development. T cells undergo a stringent selection process in the thymus to achieve self-nonself discrimination capacity and can be identified based on double-positive (DP) or single-positive (SP) CD4/CD8 expression status. We utilize a maternal separation with early weaning paradigm to study the effects of ELS on anxiety/depressive behavior and intrathymic T cell distribution. Conditions of neglect-related stress were simulated based on scheduled dam-pup separation (physical neglect) and early weaning to a high carbohydrate diet (malnutrition). Pups were subjected to one of two distinct ELS conditions: (1) daily separation with early weaning (MSEW) or (2) early weaning alone (EW) at postnatal day (PD) 14. Control pups experienced no separation and were maintained on the dam’s milk to the standard wean date (PD21). Body metrics and tissues were collected at PD21. Behavioral phenotypes were assessed at PD28–35. The results demonstrated significant stress effects and revealed an altered distribution of thymocytes within DP and SP compartments. This study provides preliminary causal evidence and provokes questions about ELS-mediated consequences on T cell immunity.
NIH/NIA T32 AG020494 NIH/NIMHD 5U54MD006882-10 UNTHSC MIG Dept. Intramural Grant
New generation of fluorescent probes for cell-based measurements of caspase Activation and mitochondrial superoxide
Authors: Mandavilli Bhaskar S , Beacham Daniel , Hu Yi-Zhen , Yang Jongtae , Chen Aimei 
Published: August 2023

Abstract
Cell health and stress readouts are critical indicators of altered or impaired function in normal and diseased states of cells, and work has been underway to develop improved small molecule sensor dyes compatible with traditional imaging and High Content Analysis (HCA) interrogation of apoptotic and mitochondrial stress pathways.
The CellEvent™ Caspase Green dye effectively reports caspase activation, but suffers complications in assay configuration when attempting to multiplex with the Green Fluorescent Protein (GFP), calcein, or other 488 laser line tools in fluorescence microscopy. Here, we describe the testing and functional characterization of a new candidate molecule for measuring apoptosis in living cells. Our sensor is comprised of a fluorogenic reporter dye that is liberated from a DEVD peptide substrate by caspase activation, with ex/em spectra of 590/610 nm, permitting easy multiplex with GFP or calcein stained neurons in both traditional and HCA microscopy configurations. MitoSOX™ Green that has specificity to superoxide like MitoSOX™ Red dye. In addition, it has better spectral properties and works with GFP filters in microscopy, and allows for measurement of mitochondrial superoxide in RFP-expressing cells. MitoSOX™ Green Mitochondrial Superoxide Indicator also localizes to mitochondria of live cells and selectively reports superoxide generation, while ignoring other ROS and RNS species in ex vivo testing. With an Excitation/Emission profile in the GFP/FITC microscopy channel, a series of comparative studies in immortalized and neural cells are shown, highlighting photostability, specificity and signal amplitude from the dye.
These reagents are research use only, not for diagnostic purposes
Re-evaluating the role of coreceptor: LCK association in T cell receptor signalling
Authors: Zhang Justin Boxuan , Jones Claerwen M , Nguyen Angela , Thiele Daniel , Zareie Pirooz , La Gruta Nicole L 
Published: August 2023

Abstract
The CD4 and CD8 coreceptors of T cells are essential for TCR signalling. The current knowledge describes that the coreceptors serve to deliver the tyrosine kinase LCK to the CD3 complex to phosphorylate immunoreceptor tyrosine activation motifs (ITAMs) to initiate TCR signalling. Recently, CD8 was shown to prevent signalling of reverse docking TCRs by sequestering LCK away from CD3, thus restricting TCR docking orientation to peptide MHC complexes and explaining the inability of these unconventional TCRs to signal during immune responses. However, how the association of LCK with the coreceptor shapes antigen-specific TCR repertoires and affects T cell activation in vivo has not been demonstrated. We utilise LCKfree mice (in which LCK cannot bind the CD4 or CD8 coreceptors) to study the role of coreceptor-associated LCK in TCR signalling. We found that the LCKfree mutation specifically reduced CD4 T cell development while not affecting CD8 T cell output. After influenza A infection, epitope specific CD8 T cell reponses in LCKfree mice are numerically and functionally intact, whereas CD4 T cell responses are substantially reduced. Single-cell RNA sequencing data showed minor gene expression differences between WT and LCKfree activated CD8 and CD4 T cells. Contrary to our hypothesis, epitope-specific TCR analysis revealed a decreased TCR diversity in CD8 TCR repertoires in LCKfree mice, biased towards the dominant clones. In contrast, CD4 repertoire show distinct TCR usage compared to WT. In summary, we found that coreceptor: LCK association is not necessary for the generation of functional MHC restricted TCR reperotires, but it is important for the development, functions, and TCR repertoire of CD4 T cells.
Supported by grants from ARC (M07001-3237405)
A multi-level study of the effects of glucocorticoids on human T cells
Authors: Bhatt Brinda , Dell’Orso Stefania , Jenkins Lisa , Maity Tapan K , Howe Katherine N , Gadkari Manasi , Franco Luis M 
Published: August 2023

Abstract
Glucocorticoids (GCs) have been the cornerstone of immunosuppressive therapies for the past 70 years, yet the mechanisms by which they regulate human immunity remain poorly understood. Specifically, there remains a need for direct insight into how GCs regulate the functions of human T cells. We have previously demonstrated that response to GCs in humans is highly cell type-dependent. In this project, we combine high-throughput techniques to study the effects of GCs on human CD4+ and CD8+ T cells, in vivo and in vitro. As part of a clinical study in 20 healthy volunteers, T cells were purified before and 2 and 4 hours after a dose of the GC methylprednisolone. RNA-seq was performed to identify GC-responsive genes. We identified a strong transcriptional response in T cells, where increased transcript abundance predominates. While there is a high degree of overlap of GC-responsive genes and in response directionality, CD4+ T cells show a stronger and more unique response than CD8+ T cells. To understand the functional genomic consequences of GC treatment in primary T cells, we developed a protocol to simultaneously assay gene expression (RNA-seq), chromatin accessibility (ATAC-seq), and glucocorticoid receptor binding (CUT&RUN) on cells treated in vitro. We are also performing experiments using tandem mass tagging (TMT) and mass spectrometry to identify which of the differentially expressed transcripts correspond to protein-level changes. Integrating data obtained at the transcript, chromatin, and protein levels will provide us with a means to identify biologically relevant effects of glucocorticoids and will guide the selection of assays to determine the functional consequences of those effects on human T cells.
SATB1 is a master gatekeeper that limits virus-specific CD8+ T cell differentiation
Authors: Turner Stephen John , Lee Jason , Russ Brendan 
Published: August 2023

Abstract
Special AT-rich sequence binding protein-1 (SATB1) is a chromatin binding protein that has key roles in ensuring appropriate chromatin structure and remodelling during T cell development. While a role for SATB1 in both CD4+ T regulatory and CD4+ TH2 lineage specific function has been described, little is known about its role during virus-specific CD8+ T cell differentiation. Here we demonstrate that SATB1 down regulation is associated with naïve CD8+ T cell activation and subsequent differentiation. Genome wide SATB1 binding indicates that SATB1 is critical for maintaining the naïve CD8+ T cell transcriptional programs prior to activation. Overexpression of SATB1 upon CD8+ T cell activation results in major restraint of virus-specific CD8+ cell differentiation resulting in lower expression of inflammatory chemokine receptors, checkpoint molecules such as PD-1 and limits effector CD8+ T cell infiltration into infected tissues. Moreover, SATB1 over expression maintains high levels of TCF-1 expression and maintenance of the naïve T cell program. Our data suggest that SATB1 expression within naïve CD8+ T cells acts as gatekeeper for maintaining the naïve T cell program, and that down regulation upon activation is required for optimal effector CD8+ T cell differentiation.
Supported by grants from the Australian Research Council (DP170102020).
CD25 recruits inhibitory phosphatases for feedback control of B-cell receptor signaling
Authors: Sun Ruifeng , Lee Jaewoong , Robinson Mark E , Kume Kohei , Cosgun Kadriye Nehir , Chan Lai N , Leveille Etienne , Geng Huimin , Vykunta Vivasvan , Shy Brian , Marson Alexander , Meffre Eric , Müschen Markus 
Published: August 2023

Abstract
Successful initiation of the B-cell receptor (BCR) signaling, and subsequent antigen-encounter in germinal centers are both marked by sharp increases of CD25 surface-expression. Likewise, oncogenic signaling in B-cell leukemia (B-ALL) and lymphoma induces CD25-surface expression. While CD25 is known as an IL2-receptor chain on T- and NK-cells, the significance of its expression on B-cells was unclear. We discovered that, rather than functioning as an IL2-receptor chain, CD25 expressed on B-cells feedback regulates BCR-signaling or its oncogenic mimics.
Recapitulating phenotypes of genetic ablation of PKCD, SHIP1 and SHP1, conditional CD25-deletion suppressed early B-cell development but induced hyperactivation of antigen-experienced B-cells and autoimmunity. Additionally, B-cell-specific CD25 deletion resulted in formation of spontaneous germinal centers and expansion of autoreactive B cells.
Biochemical and interactome studies revealed that BCR-signaling induced PKCd-dependent CD25-phosphorylation of the CD25 cytoplasmic tail (S268) to recruit inhibitory phosphatases to the BCR complex. Upon CD25-deletion, SHIP1 and SHP1 were no longer recruited and activated to limit duration and strength of BCR-signaling. Loss of phosphatase-function, autonomous BCR-signaling and Ca2+-oscillations induced anergy and negative selection during early B-cell development, as opposed to proliferation and autoantibody production in antigen-experienced B-cells. These findings highlight the previously unrecognized role of CD25 in assembling inhibitory phosphatases to prevent chronic BCR signaling and safeguard B cell tolerance.
Gata3
ZsG-fl: a novel murine Gata3 reporter allele revealed a unique expression profile of GATA3 controlled genes in ILC2 and Th2 under in vivo condition
Authors: Gurram Rama Krishna , Wei Danping , Yu Qiao , Xi Chen , Cui Kairong , Hu Gangqing , Zheng Mingzhu , Chung Hyunwoo , Butcher Matthew J , Zhao Keji , Liu Chengyu , Khillan Jaspal S , Zhu Jinfang (Jeff) 
Published: August 2023

Abstract
The transcription factor GATA3 expression is essential for T helper-2 (Th2) cells and type 2 innate lymphoid cells (ILC2s) mediated type 2 immune responses. However, most of the studies were done in in vitro system, and such functions cannot be easily verified in vivo because the expression of the markers for identifying Th2 and ILC2s depends on GATA3. We have generated a novel GATA3 reporter mice strain carrying Gata3ZsG-flallele. This mouse carries a ZsGreen-T2A cassette at the translation initiation site along with exon 4 flanked by two loxP sites. Later, an inducible Gata3 deletion system was created by crossing Gata3ZsG-flmice with a tamoxifen-inducible Cre (CreERT2) system. This reporter mice allowed us to visualize Gata3 deleted Th2 cells and ILC2s in vivo. Transcriptome comparison of Gata3 KO ILC2s and Th2 cells revealed common and distinct expression patterns of genes under the control of the GATA3 protein. Interestingly, this study also identified some GATA3-controlled genes specifically expressed under in vivo conditions but not in vitro. Therefore, transcriptome comparison of Gata3 KO ILC2s and Th2 cells in vivo provided valuable information to investigate the GATA3-controlled type 2 immune responses.
This research was supported by the Intramural Research Programs of NIAID, NIH.
Clonally-Expanded, Thyrotoxic Autoimmune Mediator CD8+ T cells Driven by IL21 Contribute to Checkpoint Inhibitor Thyroiditis
Authors: Lechner Melissa G , Zhou Zikang , Scott Lauren N , Ortega Jessica , Huang Nicole , Chen Ho-Chung , Hoang Aline , Tafti Rana Yakhshi , Kim Kristy , Hugo Willy , Famini Pouyan , Drakaki Alexandra , Ribas Antoni , Angell Trevor E , Su Maureen A 
Published: August 2023

Abstract
Autoimmune toxicity occurs in up to 60% of patients treated with immune checkpoint inhibitor (ICI) cancer therapy and is an increasing clinical challenge with the expanding use of these treatments. Previous human studies into the cause of immune related adverse events (IRAEs) have often evaluated only circulating immune cells rather than affected tissues. Here, we directly sampled thyroid specimens from subjects with ICI-thyroiditis, one of the most common IRAEs, to determine driving mechanisms. We compared immune infiltrates in ICI-thyroiditis to those in subjects with spontaneous autoimmune Hashimoto’s thyroiditis (HT) or no thyroid disease. Single cell RNA sequencing revealed a dominant, clonally expanded population of thyroid-infiltrating cytotoxic CXCR6+ CD8+ T cells (“CD8+ autoimmune mediators”) present in ICI-thyroiditis, but not HT or healthy subjects. Furthermore, we identified a crucial role for interleukin 21, a cytokine secreted by intrathyroidal T follicular (Tfh) and T peripheral helper (Tph) cells, as a driver of these thyrotoxic CD8+ autoimmune mediators. In the presence of IL21, human CD8+ T cells acquired the autoimmune mediator phenotype with upregulation of cytotoxic molecules (IFNg, granzyme); the chemokine receptor CXCR6; and thyrotoxic capacity. We validated these findings in vivo using a novel mouse model of IRAEs, and further demonstrated that genetic inhibition of IL21 signaling protected ICI-treated mice from thyroid autoimmunity. Taken together, our data reveal novel mechanisms by which IL21+Tfh/Tph cells drive thyrotoxic CD8+ autoimmune mediators for the development of IRAEs in humans. Furthermore, these studies highlight IL21 as a potential therapeutic target in patients to prevent IRAEs.
Supported by grants from the NIH NIDDK (K08 DK129829), the American Thyroid Association, and the Aramont Charitable Foundation.