Top read articles in the last 30 days
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Abstract
Newly emerging viruses, such as severe acute respiratory syndrome coronavirus (SARS-CoV), Middle Eastern respiratory syndrome CoVs (MERS-CoV), and H7N9, cause fatal acute lung injury (ALI) by driving hypercytokinemia and aggressive inflammation through mechanisms that remain elusive. In SARS-CoV/macaque models, we determined that anti–spike IgG (S-IgG), in productively infected lungs, causes severe ALI by skewing inflammation-resolving response. Alveolar macrophages underwent functional polarization in acutely infected macaques, demonstrating simultaneously both proinflammatory and wound-healing characteristics. The presence of S-IgG prior to viral clearance, however, abrogated wound-healing responses and promoted MCP1 and IL-8 production and proinflammatory monocyte/macrophage recruitment and accumulation. Critically, patients who eventually died of SARS (hereafter referred to as deceased patients) displayed similarly accumulated pulmonary proinflammatory, absence of wound-healing macrophages, and faster neutralizing antibody responses. Their sera enhanced SARS-CoV–induced MCP1 and IL-8 production by human monocyte–derived wound-healing macrophages, whereas blockade of FcγR reduced such effects. Our findings reveal a mechanism responsible for virus-mediated ALI, define a pathological consequence of viral specific antibody response, and provide a potential target for treatment of SARS-CoV or other virus-mediated lung injury.
Authors
Li Liu, Qiang Wei, Qingqing Lin, Jun Fang, Haibo Wang, Hauyee Kwok, Hangying Tang, Kenji Nishiura, Jie Peng, Zhiwu Tan, Tongjin Wu, Ka-Wai Cheung, Kwok-Hung Chan, Xavier Alvarez, Chuan Qin, Andrew Lackner, Stanley Perlman, Kwok-Yung Yuen, Zhiwei Chen
Total views: 2290
Abstract
Subjects with obesity frequently have elevated serum vasopressin levels, noted by measuring the stable analog, copeptin. Vasopressin acts primarily to reabsorb water via urinary concentration. However, fat is also a source of metabolic water, raising the possibility that vasopressin might have a role in fat accumulation. Fructose has also been reported to stimulate vasopressin. Here, we tested the hypothesis that fructose-induced metabolic syndrome is mediated by vasopressin. Orally administered fructose, glucose, or high-fructose corn syrup increased vasopressin (copeptin) concentrations and was mediated by fructokinase, an enzyme specific for fructose metabolism. Suppressing vasopressin with hydration both prevented and ameliorated fructose-induced metabolic syndrome. The vasopressin effects were mediated by the vasopressin 1b receptor (V1bR), as V1bR-KO mice were completely protected, whereas V1a-KO mice paradoxically showed worse metabolic syndrome. The mechanism is likely mediated in part by de novo expression of V1bR in the liver that amplifies fructokinase expression in response to fructose. Thus, our studies document a role for vasopressin in water conservation via the accumulation of fat as a source of metabolic water. Clinically, they also suggest that increased water intake may be a beneficial way to both prevent or treat metabolic syndrome.
Authors
Ana Andres-Hernando, Thomas J. Jensen, Masanari Kuwabara, David J. Orlicky, Christina Cicerchi, Nanxing Li, Carlos A. Roncal-Jimenez, Gabriela E. Garcia, Takuji Ishimoto, Paul S. Maclean, Petter Bjornstad, Laura Gabriela Sanchez-Lozada, Mehmet Kanbay, Takahiko Nakagawa, Richard J. Johnson, Miguel A. Lanaspa
Total views: 2064
Abstract
In severe cases of coronavirus disease 2019 (COVID-19), viral pneumonia progresses to respiratory failure. Neutrophil extracellular traps (NETs) are extracellular webs of chromatin, microbicidal proteins, and oxidant enzymes that are released by neutrophils to contain infections. However, when not properly regulated, NETs have the potential to propagate inflammation and microvascular thrombosis — including in the lungs of patients with acute respiratory distress syndrome. We now report that sera from patients with COVID-19 have elevated levels of cell-free DNA, myeloperoxidase-DNA (MPO-DNA), and citrullinated histone H3 (Cit-H3); the latter 2 are specific markers of NETs. Highlighting the potential clinical relevance of these findings, cell-free DNA strongly correlated with acute-phase reactants, including C-reactive protein, D-dimer, and lactate dehydrogenase, as well as absolute neutrophil count. MPO-DNA associated with both cell-free DNA and absolute neutrophil count, while Cit-H3 correlated with platelet levels. Importantly, both cell-free DNA and MPO-DNA were higher in hospitalized patients receiving mechanical ventilation as compared with hospitalized patients breathing room air. Finally, sera from individuals with COVID-19 triggered NET release from control neutrophils in vitro. Future studies should investigate the predictive power of circulating NETs in longitudinal cohorts and determine the extent to which NETs may be novel therapeutic targets in severe COVID-19.
Authors
Yu Zuo, Srilakshmi Yalavarthi, Hui Shi, Kelsey Gockman, Melanie Zuo, Jacqueline A. Madison, Christopher Blair, Andrew Weber, Betsy J. Barnes, Mikala Egeblad, Robert J. Woods, Yogendra Kanthi, Jason S. Knight
Total views: 1888
Abstract
Extra-pulmonary manifestations of COVID-19 are associated with a much higher mortality rate. Yet, little is known about the pathogenesis of systemic complications of COVID-19. Here, we create a murine model of SARS-CoV-2 induced severe systemic toxicity and multi-organ involvement by expressing the human ACE2 transgene in multiple tissues via viral delivery followed by systemic administration of SARS-CoV-2. The animals develop a profound phenotype within 7 days with severe weight loss, morbidity and failure to thrive. We demonstrate there is metabolic suppression of oxidative phosphorylation and the tri-carboxylic acid (TCA) cycle in multiple organs with neutrophilia, lymphopenia and splenic atrophy mirroring human COVID-19 phenotypes. Animals had a significantly lower heart rate and electron microscopy demonstrated myofibrillar disarray and myocardial edema, a common pathogenic cardiac phenotype in human COVID-19. We perform metabolomic profiling of peripheral blood and identify a panel of TCA cycle metabolites that serve as biomarkers of depressed oxidative phosphorylation. Finally, we observed that SARS-CoV-2 induces epigenetic changes of DNA methylation, that affects expression of immune response genes and could in part contribute to COVID-19 pathogenesis. Our model suggests that SARS-CoV-2 induced metabolic reprogramming and epigenetic changes in internal organs could contribute to systemic toxicity and lethality in COVID-19.
Authors
Shen Li, Feiyang Ma, Tomohiro Yokota, Gustavo Garcia Jr., Amelia Palermo, Yijie Wang, Colin Farrell, Yu-Chen Wang, Rimao Wu, Zhiqiang Zhou, Calvin Pan, Marco Morselli, Michael A. Teitell, Sergey Ryazantsev, Gregory A. Fishbein, Johanna ten Hoeve, Valerie A. Arboleda, Joshua Bloom, Barbara J. Dillon, Matteo Pellegrini, Aldons J. Lusis, Thomas G. Graeber, Vaithilingaraja Arumugaswami, Arjun Deb
Total views: 1315
Abstract
BACKGROUND Reprogramming of host metabolism supports viral pathogenesis by fueling viral proliferation, by providing, for example, free amino acids and fatty acids as building blocks.METHODS To investigate metabolic effects of SARS-CoV-2 infection, we evaluated serum metabolites of patients with COVID-19 (n = 33; diagnosed by nucleic acid testing), as compared with COVID-19–negative controls (n = 16).RESULTS Targeted and untargeted metabolomics analyses identified altered tryptophan metabolism into the kynurenine pathway, which regulates inflammation and immunity. Indeed, these changes in tryptophan metabolism correlated with interleukin-6 (IL-6) levels. Widespread dysregulation of nitrogen metabolism was also seen in infected patients, with altered levels of most amino acids, along with increased markers of oxidant stress (e.g., methionine sulfoxide, cystine), proteolysis, and renal dysfunction (e.g., creatine, creatinine, polyamines). Increased circulating levels of glucose and free fatty acids were also observed, consistent with altered carbon homeostasis. Interestingly, metabolite levels in these pathways correlated with clinical laboratory markers of inflammation (i.e., IL-6 and C-reactive protein) and renal function (i.e., blood urea nitrogen).CONCLUSION In conclusion, this initial observational study identified amino acid and fatty acid metabolism as correlates of COVID-19, providing mechanistic insights, potential markers of clinical severity, and potential therapeutic targets.FUNDING Boettcher Foundation Webb-Waring Biomedical Research Award; National Institute of General and Medical Sciences, NIH; and National Heart, Lung, and Blood Institute, NIH.
Authors
Tiffany Thomas, Davide Stefanoni, Julie A. Reisz, Travis Nemkov, Lorenzo Bertolone, Richard O. Francis, Krystalyn E. Hudson, James C. Zimring, Kirk C. Hansen, Eldad A. Hod, Steven L. Spitalnik, Angelo D’Alessandro
Total views: 946
Abstract
Small noncoding RNAs, miRNAs (miRNAs), are emerging as important modulators in the pathogenesis of kidney disease, with potential as biomarkers of kidney disease onset, progression, or therapeutic efficacy. Bulk tissue small RNA-sequencing (sRNA-Seq) and microarrays are widely used to identify dysregulated miRNA expression but are limited by the lack of precision regarding the cellular origin of the miRNA. In this study, we performed cell-specific sRNA-Seq on tubular cells, endothelial cells, PDGFR-β+ cells, and macrophages isolated from injured and repairing kidneys in the murine reversible unilateral ureteric obstruction model. We devised an unbiased bioinformatics pipeline to define the miRNA enrichment within these cell populations, constructing a miRNA catalog of injury and repair. Our analysis revealed that a significant proportion of cell-specific miRNAs in healthy animals were no longer specific following injury. We then applied this knowledge of the relative cell specificity of miRNAs to deconvolute bulk miRNA expression profiles in the renal cortex in murine models and human kidney disease. Finally, we used our data-driven approach to rationally select macrophage-enriched miR-16-5p and miR-18a-5p and demonstrate that they are promising urinary biomarkers of acute kidney injury in renal transplant recipients.
Authors
Katie L. Connor, Oliver Teenan, Carolynn Cairns, Victoria Banwell, Rachel A.B. Thomas, Julie Rodor, Sarah Finnie, Riinu Pius, Gillian M. Tannahill, Vishal Sahni, Caroline O.S. Savage, Jeremy Hughes, Ewen M. Harrison, Robert B. Henderson, Lorna P. Marson, Bryan R. Conway, Stephen J. Wigmore, Laura Denby
Total views: 891
Abstract
Evaluation of potential immunity against the novel severe acute respiratory syndrome (SARS) coronavirus that emerged in 2019 (SARS-CoV-2) is essential for health, as well as social and economic recovery. Generation of antibody response to SARS-CoV-2 (seroconversion) may inform on acquired immunity from prior exposure, and antibodies against the SARS-CoV-2 spike protein receptor binding domain (S-RBD) are speculated to neutralize virus infection. Some serology assays rely solely on SARS-CoV-2 nucleocapsid protein (N-protein) as the antibody detection antigen; however, whether such immune responses correlate with S-RBD response and COVID-19 immunity remains unknown. Here, we generated a quantitative serological ELISA using recombinant S-RBD and N-protein for the detection of circulating antibodies in 138 serial serum samples from 30 reverse transcription PCR–confirmed, SARS-CoV-2–hospitalized patients, as well as 464 healthy and non–COVID-19 serum samples that were collected between June 2017 and June 2020. Quantitative detection of IgG antibodies against the 2 different viral proteins showed a moderate correlation. Antibodies against N-protein were detected at a rate of 3.6% in healthy and non–COVID-19 sera collected during the pandemic in 2020, whereas 1.9% of these sera were positive for S-RBD. Approximately 86% of individuals positive for S-RBD–binding antibodies exhibited neutralizing capacity, but only 74% of N-protein–positive individuals exhibited neutralizing capacity. Collectively, our studies show that detection of N-protein–binding antibodies does not always correlate with presence of S-RBD–neutralizing antibodies and caution against the extensive use of N-protein–based serology testing for determination of potential COVID-19 immunity.
Authors
Kathleen M. McAndrews, Dara P. Dowlatshahi, Jianli Dai, Lisa M. Becker, Janine Hensel, Laura M. Snowden, Jennifer M. Leveille, Michael R. Brunner, Kylie W. Holden, Nikolas S. Hopkins, Alexandria M. Harris, Jerusha Kumpati, Michael A. Whitt, J. Jack Lee, Luis L. Ostrosky-Zeichner, Ramesha Papanna, Valerie S. LeBleu, James P. Allison, Raghu Kalluri
Total views: 875
Abstract
Congenital Zika syndrome (CZS) is associated with microcephaly and various neurological, musculoskeletal, and ocular abnormalities, but the long-term pathogenesis and postnatal progression of ocular defects in infants are not well characterized. Rhesus macaques are superior to rodents as models of CZS because they are natural hosts of the virus and share similar immune and ocular characteristics, including blood–retinal barrier characteristics and the unique presence of a macula. Using a previously described model of CZS, we infected pregnant rhesus macaques with Zika virus (ZIKV) during the late first trimester and characterized postnatal ocular development and evolution of ocular defects in 2 infant macaques over 2 years. We found that one of them exhibited colobomatous chorioretinal atrophic lesions with macular and vascular dragging as well as retinal thinning caused by loss of retinal ganglion neuron and photoreceptor layers. Despite these congenital ocular malformations, axial elongation and retinal development in these infants progressed at normal rates compared with healthy animals. The ZIKV-exposed infants displayed a rapid loss of ZIKV-specific antibodies, suggesting the absence of viral replication after birth, and did not show any behavioral or neurological defects postnatally. Our findings suggest that ZIKV infection during early pregnancy can impact fetal retinal development and cause congenital ocular anomalies but does not appear to affect postnatal ocular growth.
Authors
Glenn Yiu, Sara M. Thomasy, M. Isabel Casanova, Alexander Rusakevich, Rebekah I. Keesler, Jennifer Watanabe, Jodie Usachenko, Anil Singapuri, Erin E. Ball, Eliza Bliss-Moreau, Wendi Guo, Helen Webster, Tulika Singh, Sallie Permar, Amir Ardeshir, Lark L. Coffey, Koen K.A. Van Rompay
Total views: 818
Abstract
Dedifferentiation has been implicated in β cell dysfunction and loss in rodent diabetes. However, the pathophysiological significance in humans remains unclear. To elucidate this, we analyzed surgically resected pancreatic tissues of 26 Japanese subjects with diabetes and 11 nondiabetic subjects, who had been overweight during adulthood but had no family history of diabetes. The diabetic subjects were subclassified into 3 disease stage categories, early, advanced, and intermediate. Despite no numerical changes in endocrine cells immunoreactive for chromogranin A (ChgA), diabetic islets showed profound β cell loss, with an increase in α cells without an increase in insulin and glucagon double-positive cells. The proportion of dedifferentiated cells that retain ChgA immunoreactivity without 4 major islet hormones was strikingly increased in diabetic islets and rose substantially during disease progression. The increased dedifferentiated cell ratio was inversely correlated with declining C-peptide index. Moreover, a subset of islet cells converted into exocrine-like cells during disease progression. These results indicate that islet remodeling with dedifferentiation is the underlying cause of β cell failure during the course of diabetes progression in humans.
Authors
Kikuko Amo-Shiinoki, Katsuya Tanabe, Yoshinobu Hoshii, Hiroto Matsui, Risa Harano, Tatsuya Fukuda, Takato Takeuchi, Ryotaro Bouchi, Tokiyo Takagi, Masayuki Hatanaka, Komei Takeda, Shigeru Okuya, Wataru Nishimura, Atsushi Kudo, Shinji Tanaka, Minoru Tanabe, Takumi Akashi, Tetsuya Yamada, Yoshihiro Ogawa, Eiji Ikeda, Hiroaki Nagano, Yukio Tanizawa
Total views: 744
Abstract
Immune and inflammatory responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contribute to disease severity of coronavirus disease 2019 (COVID-19). However, the utility of specific immune-based biomarkers to predict clinical outcome remains elusive. Here, we analyzed levels of 66 soluble biomarkers in 175 Italian patients with COVID-19 ranging from mild/moderate to critical severity and assessed type I IFN–, type II IFN–, and NF-κB–dependent whole-blood transcriptional signatures. A broad inflammatory signature was observed, implicating activation of various immune and nonhematopoietic cell subsets. Discordance between IFN-α2a protein and IFNA2 transcript levels in blood suggests that type I IFNs during COVID-19 may be primarily produced by tissue-resident cells. Multivariable analysis of patients’ first samples revealed 12 biomarkers (CCL2, IL-15, soluble ST2 [sST2], NGAL, sTNFRSF1A, ferritin, IL-6, S100A9, MMP-9, IL-2, sVEGFR1, IL-10) that when increased were independently associated with mortality. Multivariate analyses of longitudinal biomarker trajectories identified 8 of the aforementioned biomarkers (IL-15, IL-2, NGAL, CCL2, MMP-9, sTNFRSF1A, sST2, IL-10) and 2 additional biomarkers (lactoferrin, CXCL9) that were substantially associated with mortality when increased, while IL-1α was associated with mortality when decreased. Among these, sST2, sTNFRSF1A, IL-10, and IL-15 were consistently higher throughout the hospitalization in patients who died versus those who recovered, suggesting that these biomarkers may provide an early warning of eventual disease outcome.
Authors
Michael S. Abers, Ottavia M. Delmonte, Emily E. Ricotta, Jonathan Fintzi, Danielle L. Fink, Adriana A. Almeida de Jesus, Kol A. Zarember, Sara Alehashemi, Vasileios Oikonomou, Jigar V. Desai, Scott W. Canna, Bita Shakoory, Kerry Dobbs, Luisa Imberti, Alessandra Sottini, Eugenia Quiros-Roldan, Francesco Castelli, Camillo Rossi, Duilio Brugnoni, Andrea Biondi, Laura Rachele Bettini, Mariella D’Angio’, Paolo Bonfanti, Riccardo Castagnoli, Daniela Montagna, Amelia Licari, Gian Luigi Marseglia, Emily F. Gliniewicz, Elana Shaw, Dana E. Kahle, Andre T. Rastegar, Michael Stack, Katherine Myint-Hpu, Susan L. Levinson, Mark J. DiNubile, Daniel W. Chertow, Peter D. Burbelo, Jeffrey I. Cohen, Katherine R. Calvo, John S. Tsang, NIAID COVID-19 Consortium, Helen C. Su, John I. Gallin, Douglas B. Kuhns, Raphaela Goldbach-Mansky, Michail S. Lionakis, Luigi D. Notarangelo
Total views: 741
