bluuebunny/crossref_metadata_2025_split huggingface dataset:
Affinity threshold conversion: the progressive differentiation checkpoint at which the TCRα/CD3δ signaling axis controls thymic positive selection
Authors: Canfield Jenna M , Ferrer Alejandro , Neier Steven C , Wilton Katelynn M , Stiles Robert J , Davis Tessa , Schrum Adam G , Pages Diana Gil 
Published: January 2023

Abstract
Upon positive selection of conventional αβ T cells, CD4+ CD8+ double-positive (DP) cells transition to single-positive (SP) and reduce their responsiveness to weak peptide/MHC ligands (affinity threshold conversion, ATC). We report that ATC actually begins prior to the completion of positive selection in the DP stage, and this checkpoint is where the TCRα/CD3δ signaling axis controls positive selection. We dissected ATC in the OT1 TCR transgenic system in conjunction with several different genes whose null mutations block thymic development at DP stage: β2m, CD3δ, and/or TCRα-Connecting Peptide Motif (αCPM). In the absence of MHC class I (β2m0), CD3δ or αCPM mutants were blocked at pre-selection DP stage and displayed immature, high-sensitivity to weak TCR ligands. In contrast, when MHC class I was present (β2m+), CD3δ or αCPM mutants were blocked at DP stage but underwent partial ATC; they began positive selection but did not complete it. Upon exogenous TCR engagement of partial-ATC thymocytes, the proximal signaling protein interaction network showed overall weakened activity, notably decreasing SOS1 participation linked to the downstream Ras/Raf/ERK selection pathway. Provision of high affinity peptide/MHC in FTOC rescued completion of positive selection for partial-ATC mutant thymocytes. Finally, comparing nontransgenic, polyclonal B6 vs. CD3δ0 DP thymocytes, although most cells showed equal maturation state, a subset of cells in B6 progressed in maturation relative to CD3δ0. We propose the existence of an intermediate checkpoint inside DP stage, in which ATC already begins to reduce responsiveness to selection ligands, yet further TCR signaling is required to complete positive selection.
Novel role(s) for Irf5 in controlling myelopoiesis and erythropoiesis
Authors: Barnes Betsy J , Vagrecha Anshul , LaPan Margaret , Kalfa Theodosia A. , Blanc Lionel 
Published: January 2023

Abstract
Causes of erythropoiesis dysregulation during anemia of inflammation remain largely unknown. Mammalian erythropoiesis can be divided into differentiation of early progenitors and maturation of precursors within anatomic niches called erythroblastic islands (EBI). EBIs consist of a central macrophage surrounded by differentiating erythroblasts and myeloid cells. While recent studies have focused on interactions of the macrophage and surrounding cells, much less is known about the transcription factors that regulate EBI formation and function. Data from scRNAseq revealed that interferon regulatory factor 5 (Irf5) is expressed by the central macrophage within EBIs. At steady state, Irf5−/− mice have decreased numbers of EBIs in the bone marrow (BM) with altered composition - increased CD71 (erythroid marker) and CD11b and Ly6G (myeloid markers). We also found increased numbers of reticulocytes in Irf5−/− BM. We hypothesize that Irf5 has a conserved function in mammalian blood formation by regulating the cellular output of erythroid and myeloid cells. To test this, we induced stress erythropoiesis in wild-type (wt) and Irf5−/− age- and littermate-matched mice by submandibular bleeding. Mice were bled twice (Day 0 and 2) and complete blood counts, erythropoiesis, and EBI formation monitored over recovery (12 days). Using CD44/Ter119 and Forward Scatter as markers of terminal erythropoiesis, we found that erythroid differentiation was significantly delayed in Irf5−/− mice resulting in increased mortality and corresponding to a significant decrease in EBI formation. These data identify Irf5 as a new regulator of the erythroid-myeloid balance within the EBI that results in altered function(s) during anemia of inflammation.
Cell-Intrinsic Regulation of Cytokine Responses by I-mfa Controls Eosinophil Development
Authors: Houser Jeremy S , Onopiuk Marta , Tsiokas Leonidas , Humphrey Mary Beth 
Published: January 2023

Abstract
The response of hematopoietic stem and progenitor cells to cytokines and other signals in the bone marrow (BM) niche is regulated by a complex network of cell-intrinsic factors that is still not well understood. We have identified a small cysteine-rich protein, the Inhibitor of MyoD Family A (I-mfa), as a novel regulator of hematopoiesis and lineage development. I-mfa is known to regulate β-catenin signaling, a pathway that is activated by the IL-3-family of cytokines (IL-3, IL-5, GM-CSF) which are important during myeloid lineage differentiation. We therefore hypothesized that I-mfa would influence the production of myeloid progenitors and mature cells by regulating the response to these cytokines. To test this, we compared the BM and spleens of wild-type (WT) and I-mfa-knockout (KO) mice by flow cytometry. I-mfa KO animals had expanded common myeloid progenitor and granulocyte/macrophage progenitor populations compared to WT, and showed eosinophilia in the spleen. The function of the BM was analyzed by myeloid colony forming unit (CFU-M) assays, showing significantly higher granulocyte colony output from I-mfa KO BM compared to WT. Mechanistically, myeloid progenitor cell lines over-expressing I-mfa were resistant to β-catenin activation in response to cytokine and Wnt ligand stimulation. These data taken together suggest that I-mfa is a novel regulator of eosinophil development through its regulation of β-catenin signaling downstream of cytokine receptors. These results present a new insight into disease states mediated by eosinophilia such as allergic asthma and may mechanistically underscore eosinophilia during the progression of myeloid leukemias.
The effects of macrophage-specific Vhl knockout on steady state and stress erythropoiesis in mice
Authors: Pan Szu-Yu , Tsai Pei-Zhen , Lin Shuei-Liong 
Published: January 2023

Abstract

Objective
Macrophages are known to assist erythropoiesis. However, the effect of macrophage specific Vhl knockout on erythropoiesis is unclear.

Methods
We generated Tg(Csf1r-Cre/Esr1);VhlF/F mice to achieve inducible macrophage-specific Vhl knockout. Tg(Csf1r-Cre/Esr1);ROSA26CAG-tdTomato/+ was also generated to examine the knockout efficiency.
Erythropoiesis was determined by analyses of complete blood count (CBC), spleen weight, and cell surface expression of TER-119 and CD71 in the bone marrow and spleen. Based on FSC-A and surface CD71 expression, we defined three different red blood cell (RBC) maturation stages as erythroblast, reticulocyte, and mature RBC. Stress erythropoiesis was induced by administration of recombinant human erythropoietin (rhEPO) 4U/gBW subcutaneously thrice per week for 6 doses.

Results
Tamoxifen administration in Tg(Csf1r-Cre/Esr1);ROSA26CAG-tdTomato/+ mice resulted in expression of tdTomato in CD11b(+)F4/80(+) cells in the spleen (79%) and peripheral blood mononuclear cell (PBMC) (48%).
In steady state erythropoiesis, tamoxifen administration in Tg(Csf1r-Cre/Esr1);VhlF/F mice did not result in changes of CBC, spleen weight, ratio of TER-119(+) cells in live cells, or RBC maturation stages in the spleen and bone marrow.
In stress erythropoiesis, administration of rhEPO resulted in polycythemia. However, no significant changes in Hct, ratio of TER-119(+) cells in live cells, or RBC maturation stages could be observed between Tg(Csf1r-Cre/Esr1);VhlF/F and littermate control mice after tamoxifen administration.

Conclusion
Macrophage specific knockout of Vhl in mice did not have significant effects on steady state erythropoiesis and rhEPO induced stress erythropoiesis.
B cells sialylate bone marrow progenitors to inhibit granulocyte production
Authors: Irons Eric Edward , Lee-Sundlov Melissa , Zhu Yuqi , Neelamegham Sriram , Hoffmeister Karin , Lau Joseph 
Published: January 2023

Abstract
Effective hematopoiesis is predicated on the utilization of limited resources and space in the bone marrow during homeostasis and stress. During acute inflammation, secreted factors induce the egress of mature B cells from the medullary compartment, reclaiming space for the emergency proliferation of myeloid precursors. However, it remains unclear whether reciprocal mechanisms between B cells and myeloid cells exist during homeostasis. Recent work by our group has demonstrated the ability of extracellular glycosyltransferases to remodel plasma membrane glycans, altering cell sensitivity to growth factors. Here, we report that B cells secrete active ST6GAL1 sialyltransferase, capable of glycosylating cells by a non-cell autonomous, extrinsic mechanism. B cells secreted ST6GAL1 to glycosylate hematopoietic progenitors in co-culture, suppressing G-CSF-driven neutrophil production. In vivo, B cell-derived ST6GAL1 restored circulating enzyme levels and altered the sialylation of diverse hematopoietic populations after transplantation into St6gal1-deficient mice. In the bone marrow, colonizing IgD+ mature B cells colocalized with regions rich in sialylation. Finally, in the bone marrow of multiple myeloma patients, expression of ST6GAL1 correlated negatively with neutrophil abundance. Our findings underscore a novel mechanism of cross-talk between mature lymphocytes and myeloid progenitors involving paracrine extracellular sialylation, with potential implications for human disease.
Altered Gut DNA virome diversity associated HMGB1 release regulates reactive Astrocytes-induced IL6 release preferably via TLR4-NFkB pathway in experimental Gulf War Illness
Authors: Seth Ratanesh K , Bose Dipro , Saha Punnag , Kimono Diana , Mondal Ayan , Lloyd Patricia Janulewicz , Klimas Nancy , Horner Ronnie D , Sullivan Kimberly , Lim Efrem S , Nagarkatti Mitzi , Nagarkatti Prakash S. , Chatterjee Saurabh 
Published: January 2023

Abstract
In a recent study, we showed that the gut DNA bacteriophage dysbiosis in Gulf War Illness (GWI) was strongly associated with compromised intestinal epithelial cell integrity, increased circulatory IL6 and neuroinflammation. The current study further investigates the mechanism of DNA bacteriophage-IL6 axis in neuroinflammation. Advancing the previous findings, we show that viral dysbiosis positively correlated with high mobility group box protein 1 (HMGB1; a damage-associated molecular pattern) expression and release in circulation following GWI induction in mice. The circulatory HMGB1 activated brain Astrocytes via altering brain endothelial tight junction proteins and crossing the blood-brain barrier. Interestingly, both in GWI mice and mouse primary Astrocytes cell culture showed an increased brain IL6 mRNA and subsequent protein expression. However, GWI mice treated with Ribavirin (used for partial gut viral sterility) showed decreased intestinal HMGB1 and brain IL6 expression. Mechanistically, HMGB1 activated innate immune response via IRAKs-IKKα-NFkB instead of either RAGE-MAPK or PI3K-mTOR pathway. Surprisingly, inhibition of RAGE or PI3K pathway in HMGB1 primed mouse Astrocyte cells showed a significant increase in IL6 expression and release suggesting NFkB activation as a preferential pathway in GWI-Astrocyte-induced IL6 release. In summary, GWI-associated gut viral dysbiosis associated intestinal HMGB1 release activates brain Astrocytes and IL6 release via toll-like receptor 4-NFkB dependent pathway, thus causing neuroinflammation in GWI. The above mechanism can form a basis for studying inflammation-associated neurocognitive abnormalities in GWI.
Brain transforms natural killer cells that exacerbate brain edema after intracerebral hemorrhage
Authors: Liu Qiang , Li Zhiguo , Li Minshu , Shi Samuel , Zhu Zilong , Zhang Xiaoan 
Published: January 2023

Abstract
Perihematomal edema (PHE) occurs within hours after intracerebral hemorrhage (ICH), leading to secondary injury manifested by impaired blood-brain-barrier (BBB) integrity and adjacent tissue destruction. To dissect mechanisms underlying PHE formation, we profiled human and mouse perihematomal tissues and identified natural killer (NK) cells as a predominant immune cell subset that outnumbers other infiltrating immune cell types during early stage of ICH. Unbiased clustering of single cell transcriptional profiles revealed two major NK cell subsets in the brain following ICH that possess either high cytotoxicity or robust chemokine production features, which distinguish them from NK cells in the periphery. NK cells exacerbate BBB disruption and brain edema after ICH via cytotoxicity toward cerebral endothelial cells and recruitment of neutrophils that augment focal inflammation. Thus, brain-bounding NK cells acquire specific features that contribute to PHE formation and neurological deterioration following ICH.
Clonally expanded CD8 T cells patrol Alzheimer’s cerebrospinal fluid
Authors: Gate David , Saligrama Naresha , Leventhal Olivia , Davis Mark M , Wyss-Coray Tony 
Published: January 2023

Abstract
Alzheimer’s disease (AD) is an incurable neurodegenerative disorder in which neuroinflammation plays a critical function. Yet, little is known about the contribution of the adaptive immune response in AD. Here we used integrated analyses of multiple cohorts to identify peripheral and central adaptive immune changes in AD. First, we performed mass cytometry of peripheral blood mononuclear cells and discovered an immune signature of AD consisting of increased numbers of CD8+ T effector memory CD45RA+ (TEMRA) cells. In a second cohort, we found that CD8+ TEMRA cells were negatively associated with cognition. Furthermore, single cell RNA sequencing revealed their enhanced T cell receptor (TCR) signaling. Notably, by utilizing multiple single cell TCR sequencing strategies on a third cohort, we discovered clonally expanded CD8+ TEMRA cells in patient cerebrospinal fluid (CSF). Finally, we used machine learning, cloning, and peptide screens to demonstrate specificity of clonally expanded AD CSF TCRs to two separate Epstein-Barr virus antigens. These results reveal a novel blood-CSF adaptive immune response in AD and provide evidence of clonal, antigen-experienced T cells patrolling the intrathecal space of brains affected by age-related neurodegeneration.
LRRK2-mediated microglial activation via NFATc2: a novel mechanism of neurotoxic inflammation in synucleinopathies
Authors: Kwon Somin , Beilina Alexandra , Smith Nathan , Li Yan , Kim Minhyung , Kumaran Ravindran , Kaganovich Alice , Mamais Adamantios , Adam Anthony , Iba Michiyo , Lee Won-Jae , Shin Soo-Jean , Rissman Robert , You Sungyong , Lee Seung-Jae , Singleton Andrew B , Cookson Mark R , Masliah Eliezer , Kim Changyoun 
Published: January 2023

Abstract
Neuroinflammation is a key pathological feature of a set of neurological disorders called synucleinopathies, which are characterized by abnormal a-synuclein (a-syn) dynamics and include Parkinson’s disease (PD), dementia with Lewy Bodies (DLB), and multiple system atrophy (MSA). Microglia, the resident macrophages of the central nervous system, are critical for orchestrating the inflammatory response in these diseases. In particular, microglia can directly bind neuron-released a-syn via receptors such as Toll-like receptor 2 (TLR2) to adopt a reactive phenotype. Here we explored the pathogenic role of Leucine-rich repeat kinase 2 (LRRK2), a PD-associated gene also known to be highly expressed in T cells, in microglial activation. We observed that neuron-released a-syn enhances LRRK2 kinase activity in microglia in a TLR2-dependent manner to induce the release of neurotoxic cytokines, TNFa and IL-6. We further determined that LRRK2 directly modulated nuclear translocation of activated T-cells cytoplasmic 2 (NFATc2) through multi-site phosphorylation. As such, modulating the LRRK2-NFATc2 cascade may be a promising therapeutic strategy for ameliorating neuroinflammation in synucleinopathies.
IL-9 promotes allergic lung inflammation by differentially affecting macrophage populations
Authors: Fu Yongyao , Kaplan Mark H 
Published: January 2023

Abstract
IL-9 promotes to the development of allergic lung disease through several responsive populations including mast cells, lymphocytes and eosinophils. However, it is not known if these represent the entire IL-9-responsive cell repertoire. In this study, we detected high IL-9R expression on macrophages and these cells occupied a large proportion of IL-9R+ cells in allergic lung. Allergic inflammation leads to a decrease in the number of alveolar macrophages (AM) in wild type mice. However, in Il9r−/− mice, the AM population is not diminished as greatly, suggesting that IL-9 represses AM self-renewal. The level of the IL-9R expression on blood monocyte is corelated with CCR2 expression, which is required for blood monocyte migration to the inflammatory site. In the chronic allergic airway disease model, the circulating monocyte population decreased coincident with an increase in the number of interstitial macrophages in the control mice compared to the Il9r−/− mice, suggesting IL-9 promotes monocyte migration and differentiation in the lung. Interestingly, IL-9 also induces a CD11c+ interstitial macrophage population in the allergic lung. Adoptive transfer of CD11c+ wild type macrophages to the Il9r−/− mice increased the inflammatory response. Thus, our study demonstrated that macrophages are important IL-9-responsive populations in allergic lung disease, and that IL-9 inhibits AM numbers as it promotes the development of pro-inflammatory CD11c+ and CD11c− interstitial macrophages. This balance is important in determining the level of allergic inflammation in the lung.
Cellular senescence and SASP in the pathobiology of IFN-γhigh severe asthma
Authors: Kale Sagar Laxman , Gorry Michael , Ray Prabir , Ray Anuradha 
Published: January 2023

Abstract

Background
5–10% of severe asthmatics are resistant to corticosteroids but account for 50% of health care costs spent on asthma care in the US and in Europe. 30–40% of corticosteroid-resistant severe asthmatic patients show elevated IFN-γ levels (Type1 immune response) in BAL cells that is closely associated with expression of CXCL10, a downstream IFN-γ target, and a marker of senescence associated secretory phenotype (SASP).

Objective
The goal of this study was to evaluate the role of SASP in severe asthma associated with an elevated level of corticosteroid-refractory IFN-γ in the airways.

Methods
Wild type BALB/c and IFN-γ−/− mice were sensitized with house dust mite (HDM) in combination with cdi-GMP and then subsequently repeatedly challenged with HDM. Lungs from these and control mice were subjected to either RNA-seq analysis or used for β-gal staining to demonstrate cellular senescence.

Results
Whole lungs from WT mice subjected to the severe asthma (SA) model demonstrated significantly higher expression of several SASP genes which included p16INK4a, CXCL10, MMP12 and IL-6 as compared to that detected in naïve WT mice. p16INK4a is a key regulator of premature cellular senescence that arrests cell cycle in G1 phase by inhibiting CDK4 and CDK6 and has been associated with corticosteroid resistance. Further, the SASP genes p16INK4a, CXCL10 and CCL8 were downregulated in the absence of IFN-γ suggesting a possible role of elevated IFN-γ in SASP induction. The lung sections from mice subjected to the SA model showed increased numbers of b-gal positive cells as compared to that found in control mice.

Conclusion
SASP may underlie persistent inflammation and corticosteroid resistance observed in a subset of severe asthma patients.
Mast cell hyperplasia underlies respiratory syncytial virus infection-induced predisposition for asthma
Authors: St. John Ashley L , Balla Jozef 
Published: January 2023

Abstract
Asthma is a chronic inflammatory airway disease, which affects approximately 300 million people worldwide. A growing number of epidemiological cohort studies supports an association between pediatric allergic asthma susceptibility and prior respiratory syncytial virus (RSV) infection. In this study, we aimed to experimentally test whether RSV infection promotes the subsequent development of allergic asthma. Either wild type mice or mast cell-deficient congenic KitW-sh mice were infected with RSV or sterile vehicle. After infection clearance, the mice were sensitized to Ragweed (A. artemisiifolia) pollen allergens and subsequently challenged intranasally with Ragweed to induce asthma. Disease severity was measured as airway hyperreactivity to inhaled β-methylcholine using a mechanical ventilator. RSV caused an acute and productive infection in mice, which was associated with a rapid cytokine response in the lungs. In our murine allergic asthma model, the wild type animals which had previously cleared the RSV infection developed more severe disease, when compared to mice that have not experienced RSV. We found that there was a sustained increase in the numbers of airway mast cells following the resolution of an acute RSV infection. The induction of allergic asthma disease in our animal model was dependent on mast cells, as it was strongly attenuated in mast cell-deficient KitW-sh mice. Furthermore, there was no potentiation of allergic asthma severity by a previous RSV infection in Sash mice, indicating this process is mast cell-dependent. Thus, RSV induces airway mast cell hyperplasia, which predisposes mice for more severe allergic responses.
TAK1 contributes to IgE-FcɛRI-mediated calcium mobilization and mast cell degranulation
Authors: Watson Colton J. F. , Rouillard Melissa M. , Crozier Robert W. E. , Fajardo Val A. , MacNeil Adam J. 
Published: January 2023

Abstract
Allergic inflammation is an inappropriate immune response, typically triggered by activated mast cells that have been IgE-sensitized to innocuous environmental agents. Allergic inflammatory events can be split into two phases, early and late, initiated by allergen-mediated mast cell activation. The early phase of the allergic response occurs within minutes of an allergen binding and crosslinking IgE-FcɛRI complexes on the surface of a sensitized mast cell. This recognition of a perceived ‘threat’ rapidly induces mast cell activation and subsequent release of pro-inflammatory mediators from preformed granules, a process known as degranulation. We have identified TAK1 as a novel contributor to induced mast cell signaling events and aim to characterize the mechanistic contribution of TAK1 in mast cell degranulation. To this end, we have employed a primary murine model of bone marrow-derived mast cells (BMMC) to examine contributions of TAK1 to IgE-mediated calcium mobilization and degranulation. β-hexosaminidase release assays and Indo-1-based spectrofluorometry demonstrated a significant inhibition (−67% ±1.44 p&lt;0.0001) in degranulation and a reduction in calcium transients (both peak amplitude p&lt;0.01 and area under curve p&lt;0.05) in allergically-activated BMMCs treated with the TAK1 inhibitor, 5Z-7-oxozeaneol (OZ). These results were supported by restoration of normal degranulation with the use of an inactive OZ analog (5Z), whereas an alternative TAK1 inhibitor (AZ) also resulted in degranulation inhibition (−32% ± 2.64 p&lt;0.0001). These results provide novel evidence to support the mechanistic control of mast cell degranulation by TAK1, highlighting its potential as a therapeutic target for allergic pathologies.