Research
Abstract
The stimulator of interferon genes (STING) protein senses cyclic di-nucleotides released in response to double stranded DNA, and functions as an adaptor molecule for type I interferon (IFN-I) signaling by activating IFN-I stimulated genes (ISG). We found impaired T cell infiltration into the peritoneum in response to TNF-α in global and EC-specific STING-/- mice and discovered that T cell transendothelial migration (TEM) across mouse and human endothelial cells (EC) deficient in STING was strikingly reduced compared to control EC, whereas T cells adhesion was not impaired. STING-/- T cells showed no defect in TEM or adhesion to EC, or immobilized endothelial cell expressed molecules ICAM-1 and VCAM-1 compared to WT T cells. Mechanistically, CXCL10, an ISG and a chemoattractant for T cells, was dramatically reduced in TNF-α-stimulated STING-/- EC and genetic loss or pharmacologic antagonism of IFN-type I interferon receptor (IFNAR) pathway reduced T cell TEM. Our data demonstrate a central role for EC STING during T cell TEM that is dependent on the ISG CXCL10 and on IFN-I-IFNAR signaling.
Authors
Marina Anastasiou, Gail A. Newton, Kuljeet Kaur, Francisco J. Carrillo-Salinas, Sasha A. Smolgovsky, Abraham L. Bayer, Vladimir Ilyukha, Shruti Sharma, Alexander Poltorak, Francis W. Luscinskas, Pilar Alcaide
Taspase1 orchestrates fetal liver hematopoietic stem cell and vertebrae fates through cleaving TFIIA
Abstract
Taspase1, a highly conserved threonine protease encoded by TASP1, cleaves nuclear histone modifying factors and basal transcription regulators to orchestrate diverse transcription programs. Hereditary loss-of-function mutation of TASP1 has recently been reported in human resulting in a novel anomaly complex syndrome manifested with hematological, facial, and skeletal abnormalities. Here, we demonstrate that Taspase1-mediated cleavage of TFIIAα-β, rather than of MLL1 or MLL2, in mouse embryos is required for proper fetal liver hematopoiesis and correct segmental identities of the axial skeleton. Homozygous genetic deletion of Taspase1 (Tasp1-/-) disrupted embryonic hematopoietic stem cell self-renewal and quiescence states, and axial skeleton fates. Strikingly, mice carrying knockin non-cleavable mutations of TFIIAα-β (Gtf2a1nc/nc), a well-characterized basal transcription factor, displayed more pronounced fetal liver and axial skeleton defects than those with non-cleavable MLL1 and MLL2 (Mll1nc/nc;2nc/nc), two trithorax group (Trx-G) histone H3 trimethyl transferases. Our study offers molecular insights concerning TASP1-loss human syndrome and discovers unexpected role of TFIIAα-β cleavage in embryonic cell fate decisions.
Authors
Hidetaka Niizuma, Adam C. Searleman, Shugaku Takeda, Scott A. Armstrong, Christopher Y. Park, Emily H. Cheng, James J. Hsieh
Abstract
The ectocervix is part of the lower female reproductive tract (FRT), which is susceptible to sexually transmitted infections (STI). Comprehensive knowledge of the phenotypes and T cell receptor (TCR) repertoire of tissue resident memory T cells (TRM) in human FRT is lacking. We have taken single-cell RNA sequencing approaches to simultaneously define gene expression and TCR clonotypes of the human ectocervix. There are significantly more CD8 than CD4 T cells. Unsupervised clustering and trajectory analysis identify distinct populations of CD8 T cells with IFNGhiGZMBlowCD69hiCD103low or IFNGlowGZMBhiCD69medCD103hi phenotypes. Little overlap was seen between their TCR repertoires. Immunofluorescent staining shows that CD103+ CD8 TRM cells preferentially localize in epithelium while CD69+ CD8 TRM distribute evenly in epithelium and stroma. Ex vivo assays indicate up to 14% of cervical CD8 TRM clonotypes are HSV-2 reactive in HSV-2-seropositive persons, reflecting physiologically relevant localization. Our studies identify subgroups of CD8 TRM in the human ectocervix that exhibit distinct expression of antiviral defense and tissue residency markers, anatomic locations, and TCR repertoires that target anatomically relevant viral antigens. Optimization of the location, number, and function of FRT TRM is an important approach for improving host defenses to STI.
Authors
Tao Peng, Khamsone Phasouk, Emily Bossard, Alexis Klock, Lei Jin, Kerry J. Laing, Christine Johnston, Noel A. Williams, Julie L. Czartoski, Dana Varon, Annalyssa N. Long, Jason H. Bielas, Thomas M. Snyder, Harlan Robins, David M. Koelle, M Juliana McElrath, Anna Wald, Lawrence Corey, Jia Zhu
Abstract
Obesity is a risk factor for gallbladder cancer (GBC) development and correlates with shorter overall survival. Leptin, derived from adipocytes, has been suggested to contribute to the growth of cancer cells. However, the detailed mechanism of leptin in GBC drug resistance remains uninvestigated. In this study, it is clinically relevant that GBC patients with a higher BMI (BMI ≥ 24 kg/m2) (n=30) were associated with increased GBC risks, including survival. Moreover, obese NOD/SCID mice exhibited a higher circulating concentration of leptin, which is associated with GBC growth and attenuated gemcitabine efficacy. We further revealed that leptin can inhibit gemcitabine-induced GBC cell death through myeloid cell leukemia 1 (MCL1) activation. The transcription factor CCAAT/enhancer-binding protein delta (CEBPD) is responsive to activated signal transducers and activators of transcription 3 (pSTAT3) and contributes to MCL1 transcriptional activation upon leptin treatment. In addition, MCL1 mediates leptin-induced mitochondrial fusion and is associated with GBC cell survival. This study suggests the involvement of the pSTAT3/CEBPD/MCL1 axis in leptin-induced mitochondrial fusion and survival. It provides a new therapeutic target to improve the efficacy of gemcitabine in GBC patients.
Authors
Wei-Jan Wang, Hong-Yue Lai, Fei Zhang, Wan-Jou Shen, Pei-Yu Chu, Hsin-Yin Liang, Ying-Bin Liu, Ju-Ming Wang
Abstract
Estrogen-related receptor gamma (Esrrg) is a murine lupus susceptibility gene associated with T cell activation. Here, we report that Esrrg controls regulatory T cells (Treg) through mitochondria homeostasis. Esrrg deficiency impaired the maintenance and function of Treg cells, leading to global T cell activation and autoimmunity in aged mice. Further, Esrrg-deficient Treg cells presented an impaired differentiation into follicular Treg (Tfr) cells that enhanced follicular helper T cells (Tfh) responses. Mechanistically, Esrrg-deficient Treg cells presented with dysregulated mitochondria with decreased oxygen consumption as well as ATP and NAD+ production. In addition, Esrrg-deficient Treg cells exhibited decreased phosphatidylinositol and TGF-β signaling pathways and increased mTORC1 activation. We found that the expression of human ESRRG, which is high in Treg cells, was lower in CD4+ T cells from lupus patients than in healthy controls. Finally, knocking down ESRRG in Jurkat T cells decreased their metabolism. Together, our results reveal a critical role of Esrrg in the maintenance and metabolism of Treg cells, which may provide a genetic link between lupus pathogenesis and mitochondrial dysfunction in T cells.
Authors
Wei Li, Minghao Gong, Yuk-Pheel Park, Ahmed S. Elshikha, Seung-Chul Choi, Josephine Brown, Nathalie Kanda, Wen-I Yeh, Leeana Peters, Anton A. Titov, Xiangyu Teng, Todd M. Brusko, Laurence Morel
Abstract
A subset of COVID-19 patients exhibit Post-Acute Sequalae of COVID-19 (PASC), but little is known about the immune signatures associated with these syndromes. We investigated longitudinal peripheral blood samples in 50 individuals with previously confirmed SARS-CoV-2 infection, including 20 who experienced prolonged duration of COVID-19 symptoms (lasting more than 30 days; median=74 days) compared to 30 who had symptom resolution in 20 days or less. Individuals with prolonged symptom duration maintained antigen-specific T-cell response magnitudes to SARS-CoV-2 spike protein in CD4+ and cTfh populations during late convalescence while those without persistent symptoms demonstrated an expected decline. The prolonged group also displayed increased IgG avidity to SARS-CoV-2 S-protein. Significant correlations between symptom duration and both SARS-CoV-2-specific T cells and antibodies were observed. Activation and exhaustion markers were evaluated in multiple immune cell types, revealing few phenotypic differences between prolonged and recovered groups suggesting that prolonged symptom duration is not due to persistent systemic inflammation. These findings demonstrate that SARS-CoV-2-specific immune responses are maintained in patients suffering from prolonged post-COVID-19 symptom duration in contrast to those with resolved symptoms and may suggest the persistence of viral antigens as an underlying etiology.
Authors
Jacob K. Files, Sanghita Sarkar, Timothy R Fram., Sushma Boppana, Sarah Sterrett, Kai Qin, Anju Bansal, Dustin M. Long, Steffanie Sabbaj, James J. Kobie, Paul A. Goepfert, Nathan Erdmann
Abstract
We explored the potential link between chronic inflammatory arthritis and COVID-19 pathogenic and resolving macrophage pathways and their role in COVID-19 pathogenesis. We found that BALF macrophage clusters FCN1pos and FCN1posSPP1pos predominant in severe COVID-19 were transcriptionally related to synovial tissue macrophage (STM) clusters CD48highS100A12pos and CD48posSPP1pos that drive Rheumatoid Arthritis (RA) synovitis. BALF macrophage cluster FABP4pos predominant in healthy lung was transcriptionally related to STM cluster TREM2pos that governs resolution of synovitis in RA remission. Plasma concentrations of SPP1 and S100A12 (key products of macrophage clusters shared with active RA) were high in severe COVID-19 and predicted the need for Intensive Care Unit transfer, and remained high in post-COVID-19 stage. High plasma levels of SPP1 were unique to severe COVID-19 when compared to other causes of severe pneumonia, and immunohistochemistry localized SPP1pos macrophages in the alveoli of COVID-19 lung. Investigation into SPP1 mechanisms of action revealed that it drives pro-inflammatory activation of CD14pos monocytes and development of PD-L1pos neutrophils, both hallmarks of severe COVID-19. In summary, COVID-19 pneumonitis appears driven by similar pathogenic myeloid cell pathways as those in RA, and their mediators such as SPP1 might be an upstream activator of the aberrant innate response in severe COVID-19 and predictive of disease trajectory including post-COVID-19 monitoring.
Authors
Lucy MacDonald, Stefano Alivernini, Barbara Tolusso, Aziza Elmesmari, Domenico Somma, Simone Perniola, Annamaria Paglionico, Luca Petricca, Silvia L. Bosello, Angelo Carfì, Michela Sali, Egidio Stigliano, Antonella Cingolani, Rita Murri, Vincenzo Arena, Massimo Fantoni, Massimo Antonelli, Francesco Landi, Francesco Franceschi, Maurizio Sanguinetti, Iain B. McInnes, Charles McSharry, Antonio Gasbarrini, Thomas D. Otto, Mariola Kurowska-Stolarska, Elisa Gremese
Abstract
SOCS3 is the main inhibitor of the JAK/STAT3 pathway. This pathway is activated by interleukin 6 (IL-6), a major mediator of the cytokine storm during shock. To determine its role in the vascular response to shock, we challenged mice lacking SOCS3 in the adult endothelium (SOCS3iEKO) with a non-lethal dose of lipopolysaccharide (LPS). SOCS3iEKO mice died 16-24 hours post-injection after severe kidney failure. Loss of SOCS3 led to an LPS-induced type I interferon-like program, and high expression of pro-thrombotic and pro-adhesive genes. Consistently, we observed intraluminal leukocyte adhesion and NETosis, as well as retinal venular leukoembolization. Notably, heterozygous mice displayed an intermediate phenotype, suggesting a gene dose effect. In vitro studies were performed to study the role of SOCS3 protein levels in the regulation of the inflammatory response. In HUVEC, pulse-chase experiments showed that SOCS3 protein has a half-life below 20 minutes. Inhibition of SOCS3 ubiquitination and proteasomal degradation leads to protein accumulation and a stronger inhibition of IL-6 signaling and barrier function loss. Together, our data demonstrates that the regulation of SOCS3 protein levels is critical to inhibit IL-6-mediated endotheliopathy during shock and provides a promising new therapeutic avenue to prevent MODS though stabilization of endothelial SOCS3.
Authors
Nina Martino, Ramon Bossardi Ramos, Shuhan Lu, Kara Leyden, Lindsay Tomaszek, Sudeshna Sadhu, Gabrielle Fredman, Ariel Jaitovich, Peter A. Vincent, Alejandro P. Adam
Abstract
Mutations in the gene (SFTPC) encoding surfactant protein C (SP-C) are associated with interstitial lung disease in children and adults. To assess the natural history of disease, we knocked-in a familial, disease-associated SFTPC mutation, L188Q [L184Q (LQ) in mice], into the mouse Sftpc locus. Translation of the mutant proprotein, proSP-CLQ, exceeded that of proSP-CWT in neonatal alveolar type 2 epithelial (AT2) cells and was associated with transient activation of oxidative stress and apoptosis leading to impaired expansion of AT2 cells during postnatal alveolarization. Differentiation of AT2 to AT1 cells was also inhibited in ex vivo organoid culture of AT2 cells isolated from LQ mice; importantly, treatment with antioxidant promoted alveolar differentiation. Upon completion of alveolarization, SftpcLQ expression was downregulated leading to resolution of chronic stress responses; however, the failure to restore AT2 cell numbers resulted in a permanent loss of AT2 cells that was linked to decreased regenerative capacity in the adult lung. Collectively, these data support the hypothesis that susceptibility to disease in adult LQ mice is established during postnatal lung development and provide a potential explanation for the delayed onset of disease in patients with familial pulmonary fibrosis.
Authors
Sneha Sitaraman, Emily P. Martin, Cheng-Lun Na, Shuyang Zhao, Jenna Green, Hitesh Deshmukh, Anne-Karina T. Perl, James P. Bridges, Yan Xu, Timothy E. Weaver
Hematologic and systemic metabolic alterations due to Mediterranean class II G6PD deficiency in mice
Abstract
Deficiency of Glucose 6 phosphate dehydrogenase (G6PD) is the single most common enzymopathy, present in approximately 400 million humans (e.g., 5% of humans). Its prevalence is hypothesized to be due to conferring resistance to malaria. However, G6PD deficiency also results in hemolytic sequelae from oxidant stress. Moreover, G6PD deficiency is associated with kidney disease, diabetes, pulmonary hypertension, immunological defects, and neurodegenerative diseases. To date, the only available mouse models have decreased levels of G6PD due to promoter mutations, but with stable G6PD. However, human G6PD mutations are missense mutations that result in decreased enzymatic stability. As such, this results in very low activity in red blood cells (RB that cannot synthesize new protein. To generate a more accurate model, the human sequence for a severe form of G6PD deficiency (Med -) was knocked into the murine G6PD locus. As predicted, G6PD levels were extremely low in RBCs and deficient mice have increased hemolytic sequalae to oxidant stress. Non-erythroid organs had metabolic changes consistent with mild G6PD deficiency, consistent with what has been observed in humans. Juxtaposition of G6PD deficient and wild-type mice revealed altered lipid metabolism in multiple organ systems. Together, these findings both establish a new mouse model of G6PD deficiency that more accurately reflects human G6PD deficiency and also advance our basic understanding of altered metabolism in this setting.
Authors
Angelo D’Alessandro, Heather L. Howie, Ariel M. Hay, Karolina H. Dziewulska, Benjamin C. Brown, Matthew J. Wither, Matthew Karafin, Elizabeth F. Stone, Steven L. Spitalnik, Eldad A. Hod, Richard O. Francis, Xiaoyun Fu, Tiffany Thomas, James C. Zimring
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