bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deficiency of RIPK3 (receptor-interacting protein kinase 3) in antigen-presenting cells dampens the pro-inflammatory T cell response following antigen presentation.
Authors: Pilon Celeste , Lesage Sylvie , Chabot-Roy Geneviève , Levine Jerrold S , Rauch Joyce 
Published: February 2023

Abstract
STUDY OBJECTIVE: We have previously shown that RIPK3 (receptor-interacting protein kinase 3)-deficient mice are protected from the development of an induced murine model of systemic lupus erythematosus (SLE). The development of SLE autoantibodies in this model is associated with the generation of an antigen-specific T cell response. We hypothesize that RIPK3-deficient antigen-presenting cells (APCs) are impaired in generation of a robust T cell response, thereby impacting induction of SLE in our murine model.

METHODS:
We performed a complete cellular immunophenotyping on mice deficient in RIPK3, compared with wild type C57BL/6 mice. We also assessed the function of RIPK3-deficient APCs in an in vitro antigen presentation assay using ovalbumin (OVA) and OVA-specific OT-II T cells.

RESULTS:
No major differences in immune cell composition and phenotype were identified between naïve RIPK3-deficient and WT mice. However, RIPK3-deficient bone marrow-derived dendritic cells (BMDCs) were found to produce lower levels of pro-inflammatory cytokines (interleukin [IL]-6 and tumor necrosis factor [TNF]-α) following lipopolysaccharide (LPS) stimulation. Moreover, presentation of OVA by RIPK3-deficient BMDCs resulted in a lower proportion of interferon (IFN)-γ producing OT-II T cells, compared to antigen presentation by WT BMDCs. In contrast, T cell proliferation was similar whether antigen was presented by RIPK3-deficient or WT BMDCs.

CONCLUSION:
Our results suggest that RIPK3 deficiency in APCs impacts antigen presentation to T cells, identifying a possible mechanism by which RIPK3-deficient mice are protected from induction of SLE.
The Unfolded Protein Response reveals eIF2α phosphorylation as a critical factor for direct MHC class I antigen presentation.
Authors: Nagamine Brandy S , Dolan Brian P 
Published: February 2023

Abstract
Modifying direct Major Histocompatibility Class I (MHC I) antigen presentation is an attractive target for the treatment of various conditions including autoimmune diseases, chronic viral infections, and cancers. Disease perturbations alter the cellular environment, influencing the presentation of peptides to CD8+ T cells. The unfolded protein response (UPR) is a signaling pathway activated in response to unfolded proteins within the ER. Previous studies have established the relationship between the UPR and MHC I antigen presentation, but the exact mechanisms remained unknown. In this study, we utilized small inhibitory molecules to individual UPR pathway targets to investigate the effect on global MHC class I levels and specific peptide presentation. Preventing PERK pathway signaling and the resulting phosphorylation of eIF2α by GSK2656157 treatment did not change MHC I antigen presentation. However, treatment with salubrinal which has the opposite effect of GSK2656157, decreased both antigen presentation and overall cell-surface MHC I levels. Treatment with 4μ8C, an inhibitor of the IRE1α UPR activation pathway which prevents splicing of Xbp1 mRNA, also diminished MHC I antigen presentation. Unexpectedly, 4μ8C treatment led to an increase in eIF2α phosphorylation in addition to blocking IRE1α signaling. Given that salubrinal and 4μ8C increase phosphorylation levels of eIF2α while decreasing antigen presentation, we conclude that UPR signaling through PERK and the subsequent phosphorylation of eIF2α, results in a modest decrease in direct MHC I antigen presentation. These data suggest that the PERK pathway alters host antigen presentation centering on translational control by eIF2α.
Roles for STAT5 in homeostasis and function of CD103+cDC1s in non-lymphoid organs
Authors: Zhou Yifan , Babcock Rachel L. , Chrisikos Taylor T. , Patel Bhakti , Medik Yusra B. , Kahn Laura M. , Li Haiyan S. , Watowich Stephanie S. 
Published: February 2023

Abstract
Type 1 conventional dendritic cells (cDC1s) have critical roles in inducing adaptive immune responses and mediating immune tolerance. Signal Transducer and Activator of Transcription 5 (STAT5) was found to be crucial for monocyte-derived DC development; however, its role in non-lymphoid tissue CD103+cDC1s remained largely unknown. We evaluated the role of STAT5 by employing myeloid-specific Stat5-deficient mice,LysM-Cre +Stat5f/f and CD11c-Cre+Stat5f/f mice. Both strains show deficiencies in the numbers of CD103+cDC1s and alveolar macrophages (AMs) in lung, suggesting ineffective maintenance of lung homeostasis. Consistent with this concept, CD11c-Cre+Stat5f/f mice show granulocyte and monocyte accumulation in lung, accompanied by a reduction in the number of CD4+T, CD8+T, and B cells. Moreover, CD11c-Cre+Stat5-deficient mice have increased numbers of alveolar histiocytes, which are also enlarged, as well as accumulation of amorphous and eosinophilic material in alveolar spaces, alveolar histiocytosis, and proteinosis. In addition to the lung, liver CD103+cDC1s were also decreased by Stat5 depletion, however colon CD103+cDC1s were not affected. To examine cell-autonomous roles for STAT5, we generated Stat5-deficient CD103+cDC1s using our established bone marrow culture system, and tested in vitro-differentiated CD103+cDC1s for antigen presentation activity. These assays suggest Stat5 deficiency impaired CD103+cDC1s antigen cross-presentation ability. Taken together, our study showed that STAT5 is required for homeostasis and function of CD103+cDC1s in non-lymphoid organs.
MR1 expression and surface translocation in airway epithelial cells from COPD or smoker lungs is altered following exposure to IFNγ or MAIT cells.
Authors: Huber Megan E , Larson Emily , Lust Taylor N , Heisler Chelsea M , Harriff Melanie J 
Published: February 2023

Abstract
MAIT cells, a highly prevalent subset of T cells restricted by the MHC Class I-like molecule MR1, play a key role in early response to bacterial infection. Chronic obstructive pulmonary disease (COPD) pathogenesis is associated with airway inflammation, increased infiltration by CD8+ T lymphocytes, and infection-driven exacerbations. Cigarette smoke (CS), a leading cause of COPD, leads to impaired immune function of airway epithelial cells (AECs) and decreases surface expression of classical MHC Class I molecules. However, the impact of CS and COPD on MR1 expression and airway MAIT cell function is unknown. We have demonstrated that exposure to CS alters MAIT cell responses to primary AECs from healthy, COPD, or smoker lungs. Here, we examined whether CS impacts expression of MR1 mRNA or surface translocation of MR1 in these primary AEC populations as a possible mechanism for this dysregulation. Short-term treatment of AECs with CS or infection with S. pneumoniae (SP) did not alter MR1 expression in any of the donor AEC groups. However, incubating CS-treated or SP-infected AECs with MAIT cells increased MR1 expression. This upregulation may be mediated through IFNγ signaling pathways, as treatment with IFNγ alone resulted in MR1 upregulation. Our data further suggest MAIT cell- and IFNγ-mediated MR1 upregulation is altered in COPD cells. Additionally, we observed increased baseline surface expression of MR1 protein in smoker AECs and reduced surface translocation upon addition of exogenous ligand. COPD- and CS-mediated dysregulation of MR1 expression could impact MAIT cell function in airways, resulting in inflammation or reduced early response to bacteria, contributing to lower airway colonization and COPD exacerbations.
Thymic epithelial cells require the autophagy-related protein Vps34 for CD4+ T cell selection
Authors: Postoak Joshua , Yang Guan , Wu Lan , Song Wenqiang , Xiao Shiyun , Manley Nancy , Van Kaer Luc 
Published: February 2023

Abstract
The generation of a functional, self-tolerant T cell repertoire depends on interactions between developing thymocytes and antigen-presenting thymic epithelial cells (TECs). The presentation of self-antigens to developing thymocytes involves a variety of cellular processes, including proteolysis, endocytosis, vesicle trafficking, and autophagy. In our current study, we focus on the class III PI3K, Vps34, which has been implicated in autophagy and vesicle trafficking. To address the contribution of Vps34 to TEC function, we have generated mice with a TEC-specific Vps34 deficiency. Conditional mutants display progressively hypoplastic thymi with reduced TEC cellularity and altered TEC subset ratio. Additionally, when TCR transgenic lines were bred to these animals we found profound defects in the positive selection of the CD4 T lymphocyte lineage but not the CD8 T lymphocyte lineage. Interestingly, cortical TECs from mutant mice display an increased abundance of unprocessed antigen bound to surface MHCII molecules indicating altered antigen processing. Collectively, these studies identify a role for the PI3K Vps34 in maintaining TEC homeostasis and contributing to the repertoire of selecting ligands processed and presented by TECs.
Allergic and anaphylactic responses to alcohol-soluble wheat gluten in female versus male Balb/cJ mice in an adjuvant-free model
Authors: Jorgensen Rick Dean , Gao Haoran , Raghunath Rajsri , Chandra Shivam , Nagisetty Siddharth , Ng Perry KW , Gangur Venugopal 
Published: February 2023

Abstract
Wheat is a major allergenic food capable of eliciting life-threatening anaphylaxis. Food allergies including wheat allergy are growing globally, and therefore warrant further investigation. While animal studies are being conducted to advance our understanding of wheat allergy, it is unknown whether female versus male mice differ in their allergic responses to wheat gluten. Here we tested the hypothesis that alcohol-soluble wheat gluten (ASWG) when applied over the skin will sensitize both female and male mice for oral hypothermia shock response in an adjuvant-free mouse model. Balb/cJ mice were produced and kept on a plant protein-free diet during this study. Groups of adult mice (n = 8–10) were exposed to durum wheat ASWG via the skin (once a week for nine weeks), without an adjuvant using our previously reported transdermal exposure (TDE) method. In females, TDE with the ASWG elicited a significant ASWG-specific IgE antibody response. However, in males, TDE with the ASWG did not elicit a significant ASWG-specific IgE antibody response. Oral challenge of ASWG, but not vehicle, elicited significant hypothermia shock response in ASWG skin-sensitized female mice. In contrast, no significant hypothermia shock response was observed in males upon oral challenge with ASWG or vehicle. These data demonstrate that female mice are more susceptible than males to develop an allergic response and oral anaphylaxis to ASWG in this model.
Blimp-1 expressing lung ILC2s are a distinct cell population in allergic asthma
Authors: Zhang Jinyi , He Kun , Ford B. Rhodes , Hettinga Angela , Poholek Amanda C. 
Published: February 2023

Abstract
Blimp-1 is a transcription factor known to have critical roles in multiple cell types including B, T and NK cells. However, its expression and function in non-NK innate lymphoid cell populations have not been well studied. To examine the expression and function of Blimp-1 in group 2 innate lymphoid cells, we analyzed several models of type 2 immunity. We found that Blimp-1 is not highly expressed in ILC2s at steady-state, however it is induced under specific stimulation conditions. Especially, Blimp-1 expression is substantially increased in house dust mite (HDM) activated mouse lung over time. In vivo and in vitro ILC2 stimulation with cytokines show that both IL-33 and IL-10 can induce Blimp-1 expression, indicating Blimp-1 is driven by multiple signals. Interestingly, HDM driven Blimp-1 expressing ILC2 have a distinct transcriptional program compared to classically-activated ILC2s treated with IL-25 and IL-33. ILC2 that express Blimp-1 predominantly lack type 2 cytokine expression, suggesting Blimp-1 plays a role independent of cytokine production and may represent a unique functional state of ILC2 cells in settings of chronic antigen including allergic disease. Our findings therefore demonstrate a previously unappreciated Blimp-1 expressing ILC2 population with distinct features that may be important for type 2 mediated disease.
Ruxolitinib ameliorates airway hyper responsiveness and lung inflammation in a corticosteroid-resistant murine model of severe asthma
Authors: Das Rupali , Bahal Devika , Hashem Tanwir , Kammala Ananth Kumar , Subramanian Hariharan 
Published: February 2023

Abstract
Asthma prevalence has increased considerably over the decades and it is now considered as one of the most common chronic disorders in the world. While the current anti-asthmatic therapies are effective for most asthma patients, there are 10–30% subjects whose disease is not controlled by such agents and they account for about 50% of the healthcare costs of asthma. Such asthmatics develop severe asthma (SA), a condition characterized by a dominant Th1/Th17 cytokine response that is accompanied by type 2-low endotype. As JAK (Janus Kinase) signaling is very important for the activation of several cytokine pathways, we examined whether inhibition of JAKs might lessen the clinical and laboratory manifestations of SA. To that end, we employed a murine model that recapitulates the complex immune response identified in the airways of human SA patients. To induce SA, mice were sensitized with house dust mite extract (HDME) and c-di-GMP (mucosal adjuvant) and then subsequently challenged with HDME and a lower dose of c-di-GMP. In this model, treatment with the JAK inhibitor, ruxolitinib, significantly ameliorated all the features of SA, including airway hyper responsiveness and lung inflammation; cellular influx and cytokine production as well as total IgE antibody titers. Thus, these studies highlight the JAKs as critical targets for mitigating the hyper-inflammation that occurs in SA and provide the framework for their incorporation into future clinical trials for patients that have severe or difficult-to manage asthma.
Post-Thrombotic loss of the epigenetic enzyme MLL1/KMT2a in macrophages suppresses urokinase expression and may contribute to an antifibrinolytic phenotype
Authors: Sharma Sriganesh B. , Beardslee Renee A. , Luke Catherine , Dowling Abigail R. , Henke Peter K. , Moore Bethany B. , Gallagher Katherine A. , Obi Andrea T. 
Published: February 2023

Abstract

Objectives:
Macrophages (Mϕs) are critical in the process of subacute and chronic venous thrombus (VT) resolution. Epigenetic alterations can reprogram Mϕ function in chronic inflammatory states. We hypothesized that the chromatin modifying enzyme MLL1/KMT2a, which increases H3K4 trimethylation at NF-kβ targeted promoters during inflammatory processes, influences Mϕ-mediated post-thrombotic fibrinolysis.

Methods:
Bone marrow derived Mϕs (BMDMs) from C57bl6 mice and immortalized Mϕs (RAW264.7) were used for in vitro experiments. Small interfering RNAs (siRNAs) were transfected to achieve MLL1 silencing, and qPCR, immunoblotting, and chromatin immunoprecipitation (ChIP) assays were performed. In vivo, VT formation was induced by IVC ligation, after which BMDMs were harvested.

Results:
Analysis of procoagulant and antifibrinolytic transcripts in MLL1 silenced BMDMs and RAW264.7 cells revealed suppression of urokinase (Plau) mRNA and protein levels by &gt;80% and &gt;50% respectively (p&lt;0.05) relative to controls. ChIP analysis of the Plau promoter in MLL1 knockdown cells showed decreased enrichment (~4.6 fold, p=0.0216) of H3K4me3 and suggested a functional role for MLL1 to promote Plau expression. BMDMs harvested from mice 7 days post-thrombosis showed suppressed mRNA and protein levels of MLL1 (by &gt;65% and &gt;55% respectively, p&lt;0.05), PLAU (by &gt;85% and &gt;55% respectively, p&lt;0.05) levels and decreased H3K4me3 enrichment on the Plau promoter (~7.2 fold, p=0.0031) relative to controls.

Conclusions:
The post-thrombotic inflammatory state induces MLL1-mediated epigenetic modifications in the bone marrow, resulting in suppression of Mϕ urokinase expression. These changes may contribute to an antibrinolytic Mϕ phenotype.
Langerhans cells rely on good neighbors to overcome gene deficiencies.
Authors: Herbst Christopher H , Bouteau Aurélie , Igyártó Botond Z 
Published: February 2023

Abstract
We recently identified that epidermal resident Langerhans Cells (LCs) acquire gene expression fingerprints from surrounding Keratinocytes (KCs) in the form of mRNA and protein. In the present study, we aimed to determine whether this transfer can also overcome gene deficiencies. For this purpose, using the Cre/Lox system, we specifically deleted genes for Connexin 43 (Cx43), MyD88, and MHC-II in LCs. While all three genes underwent recombination, reduced protein levels were only observed for MHC-II, whereas Cx43 and MyD88 protein levels remained unaltered. Considering that KCs lack MHC-II, but express Cx43 and MyD88 at high levels, we posit that LCs can acquire gene products from surrounding KCs to overcome their own deficiencies if those products are available.
In summary, we present evidence that cells can compensate for gene deficiencies if the surrounding cells can provide. These findings highlight the limitations of cell-specific gene deletion, and could provide an explanation as to why certain gene deletions do not lead to measurable deficiencies.
Cutaneous T cells promote distinct cellular outcomes in human keratinocytes and fibroblasts
Authors: Morawski Peter A , DeBerg Hannah , Fahning Mitchell L. , Gratz Iris , Campbell Daniel J. 
Published: February 2023

Abstract
Human skin is a barrier tissue home to a highly specialized immune environment in which leukocytes coordinate with local epithelial and stromal tissue in response to physical, chemical, and biological stresses. T cells are abundant in the skin and are required for both host defense to pathogens and the subsequent repair of damaged tissue. Cutaneous lymphocytes include both resident and migratory fractions, which can be identified and isolated using expression of the cutaneous lymphocyte antigen (CLA). There are multiple subsets of CLA+ T cells, each having a distinct phenotype and functional capacity, however their precise roles in contributing to host-protective and tissue-repair responses remains incompletely understood. We assessed the function of eight different CD4+CLA+ cutaneous T cell subsets from the skin and blood, including traditional T helper lineages and a novel subset of CD4+CLA+CD103+ T cells with a tissue repair phenotype, by bulk RNAseq analysis of keratinocytes and fibroblasts following administration of activated T cell supernatants. Differential gene expression and pathway analysis reveal distinct cellular outcomes in keratinocytes and fibroblasts that depend strongly on T cell source and the activity of specific cytokines. Our findings define a diverse array of immune-induced states in the skin that are dependent on the unique functional capacity of various T cell subsets, thereby constructing a comprehensive tool to map how cutaneous T cells contribute to pathological disruption, tissue repair and return to homeostasis within human skin.
The Role of Interactions of Adaptor Protein PSTPIP2 in the Development of Autoinflammatory Disease
Authors: Pavliuchenko Nataliia , Kralova Jarmila , Fabisik Matej , Brdicka Tomas 
Published: February 2023

Abstract
PSTPIP2 is an adaptor protein, which binds multiple regulators of neutrophil signaling to suppress inflammation. The compete loss of PSTPIP2 protein in the mouse strain Pstpip2cmo results in the development of autoinflammatory disease chronic multifocal osteomyelitis (CMO), a condition resembling human CRMO. The disease is driven by an overproduction of IL-1β and deregulated activity of NADPH oxidase. The main goal of this study is to analyze the effects of PSTPIP2 interactions on leukocyte signaling pathways, IL-1β processing, ROS production by NADPH oxidase, and auto inflammation in vivo.
To achieve this, we have generated mice with mutations in major interaction sites in PSTPIP2 including W232 responsible for binding to PEST family phosphatases (PEST-PTP), and the C-terminal sequence containing major tyrosine phosphorylation sites known to bind inositide phosphatase SHIP1 (Pstpip2ΔC-t). W232A mutation resulted in enhanced ROS production by neutrophils and increased IL-1β cleavage. Moreover, some W232A mutants developed CMO symptoms. However, the kinetics was delayed and severity was milder, when compared to Pstpip2cmo strain. In contrast, Pstpip2ΔC-t mutants did not show any CMO symptoms or increased IL-1β cleavage. Interestingly, partially deregulated ROS production could still be measured in Pstpip2ΔC-t neutrophils. Collectively, our data demonstrate an important function of PEST-PTP binding to PSTPIP2 in the suppression of auto inflammation, while SHIP1 binding contributes to the regulation of neutrophil oxidative burst. The obtained data give us a novel perspective on PSTPIP2 interactome and extend our knowledge of the molecular interactions regulating physiological and pathological inflammation.
Mitochondrial respiration contributes to the interferon gamma response in antigen presenting cells
Authors: Olive Andrew J , Kiritsy Michael , Sassetti Christopher 
Published: February 2023

Abstract
To effectively control infections, antigen presenting cells act as an integration point where signaling and metabolic pathways collaboratively determine cellular activation state and shape T cell responses. The cytokine Interferon γ (IFNγ) is key to modulating multiple macrophage functions that allow the host to respond effectively to infection. How a single cytokine like IFNγ regulates parallel immune mechanisms remains unclear, limiting our ability to target IFNγ-dependent mechanisms therapeutically. We conducted a series of forward genetic screens dissecting the networks that control IFNγ-mediated expression of the key immune molecules MHCII, CD40 and PD-L1. Our multi-screen approach enabled the identification of novel pathways that control these functionally distinct markers and uncovered a new pathway of immunometabolism that requires the electron transport chain Complex I to activate IFNγ responses. Mechanistic studies demonstrate that in both mouse and human cells the loss of Complex I results in blunted IFNγ-responses that were characterized by the reduced activation of the IFNγ receptor complex and Stat1. We developed a new model of mitochondrial dysfunction using long-term treatment with Linezolid, an antibiotic used to treat TB that blocks the mitochondrial ribosome, which recapitulated defects in the IFNγ response. Furthermore, perturbation of Complex I inhibits the capacity of both macrophages and dendritic cells to stimulate T cells. Thus these studies identified a new role for mitochondrial activity as a central point where local signals are integrated to determine antigen presentation cell function.