Mice are normally unaffected by SARS-CoV-2 infection since the virus does not bind effectively to the murine version of the ACE2 receptor molecule. Here we report that induced mild pulmonary morbidities render SARS-CoV-2 refractive CD-1 mice to be susceptible to this virus. Specifically, SARS-CoV-2 infection after application of low-doses of the acute-lung-injury stimulants bleomycin or ricin caused a severe disease in CD-1 mice, manifested by sustained body weight loss and mortality rates of >50%. Further studies revealed markedly higher levels of viral RNA in the lungs, heart and serum of low-dose-ricin pretreated, as compared to non-pretreated mice. Furthermore, lung extracts prepared 2-3 days after viral infection contained subgenomic RNA and virus particles capable of replication, only when derived from the pretreated mice. The deleterious effects of SARS-CoV-2 infection were effectively alleviated by passive transfer of polyclonal or monoclonal antibodies generated against SARS-CoV-2 RBD. Thus, viral cell entry in the sensitized mice seems to depend on viral RBD binding, albeit by a mechanism other than the canonical ACE2-mediated uptake route. This unique mode of viral entry, observed over a mildly injured tissue background, may contribute to the exacerbation of COVID-19 pathologies in patients with preexisting morbidities.
Reut Falach, Liat Bar-On, Shlomi Lazar, Tamar Kadar, Ohad Mazor, Moshe Aftalion, David Gur, Yentl Evgy, Ohad Shifman, Tamar Aminov, Ofir Israeli, Inbar Cohen-Gihon, Galia Zaide, Hila Gutman, Yaron Vagima, Efi Makdasi, Dana Stein, Ronit Rosenfeld, Ron Alcalay, Eran Zahavy, Haim Levy, Itai Glinert, Amir Ben-Shmuel, Tomer Israely, Sharon Melamed, Boaz Politi, Hagit Achdout, Shmuel Yitzhaki, Chanoch Kronman, Tamar Sabo
BACKGROUND. The chemokine system of ligands and receptors is implicated in the progression of Alcohol-associated hepatitis (AH). Finding upstream regulators could lead to novel therapies. MOTHODS. The coordinated expression of chemokines in livers of healthy controls (HC) and patients with AH in two distinct cohorts of patients with various chronic liver diseases. Studies in cultured hepatocytes and in tissue-specific knockouts were used for mechanistic insight into a potential upstream regulator of chemokine expression in AH. RESULTS. Selected C-X-C chemokine members of the Interleukin-8 (IL-8) chemokine family and C-C chemokine CCl20 were highly associated with AH compared to HC, but not in patients with liver diseases of other etiologies (NAFLD or HCV). Our previous studies implicate Macrophage migration inhibitory factor (MIF) as a pleiotropic cytokine/chemokine with the potential to coordinately regulate chemokine expression in AH. LPS-stimulated expression of multiple chemokines in cultured hepatocytes was dependent on MIF. Gao-binge ethanol feeding to mice induced a similar coordinated chemokine expression in livers of wild-type mice; this was prevented in hepatocyte-specific Mif knockout (MifΔHep) mice. CONCLUSIONS. This study demonstrates that patients with AH exhibit a specific, coordinately expressed chemokine signature and hepatocyte-derived MIF might drive this inflammatory response.
Kyle L. Poulsen, Xiude D. Fan, Christopher D. Kibler, Emily Huang, Xiaoqin Wu, Megan R. McMullen, Lin Leng, Richard Bucala, Meritxell Ventura-Cots, Josepmaria Argemi, Ramon Bataller, Laura E. Nagy
Idiopathic Pulmonary Fibrosis (IPF) is characterized by aberrant repair that diminishes lung function via mechanisms that remain poorly understood. C-C chemokine receptor (CCR10) and its ligand, CCL28, were both elevated in IPF compared with normal donors. CCR10 was highly expressed by various cells from IPF lungs, most notably stage-specific embryonic antigen (SSEA)-4+ mesenchymal progenitor cells (MPCs). In vitro, CCL28 promoted the proliferation of CCR10+ MPCs while CRISPR-Cas9-mediated targeting of CCR10 resulted in the death of MPCs. Following the intravenous injection of various cells from IPF lungs into immunodeficient (NSG) mice, human CCR10+ cells initiated and maintained fibrosis in NSG mice. Eph receptor A3 (EphA3) was among the highest expressed receptor tyrosine kinases detected on IPF CCR10+ cells. Ifabotuzumab-targeted killing of EphA3+ cells significantly reduced the numbers of CCR10+ cells and ameliorated pulmonary fibrosis in humanized NSG mice. Thus, human CCR10+ cells promote pulmonary fibrosis and EphA3 mAb-directed elimination of these cells inhibits lung fibrosis.
Miriam S. Hohmann, David M. Habiel, Milena S. Espindola, Guanling Huang, Isabelle Jones, Rohan Narayanan, Ana Lucia Coelho, Justin M. Oldham, Imre Noth, Shwu-Fan Ma, Adrianne Kurkciyan, Jonathan L. McQualter, Gianni Carraro, Barry Stripp, Peter Chen, Dianhua Jiang, Paul W. Noble, William Parks, John Woronicz, Geoffrey Yarranton, Lynne A. Murray, Cory M. Hogaboam
Long noncoding RNAs (lncRNAs) are increasingly implicated in the pathology of diabetic complications. Here we examined the role of lncRNAs in monocyte dysfunction and inflammation associated with human type 2 diabetes mellitus (T2D). RNA-seq analysis of CD14+ monocytes from patients with T2D versus healthy controls revealed downregulation of anti-inflammatory and anti-proliferative genes along with several lncRNAs, including a novel divergent lncRNA DRAIR (Diabetes Regulated anti-inflammatory RNA) and its nearby gene CPEB2. High glucose and palmitic acid downregulated DRAIR in cultured CD14+ monocytes, whereas anti-inflammatory cytokines and monocyte-to-macrophage differentiation upregulated DRAIR via KLF4 transcription factor. DRAIR overexpression increased anti-inflammatory and macrophage differentiation genes but inhibited pro-inflammatory genes. Conversely, DRAIR knockdown attenuated anti-inflammatory genes, promoted inflammatory responses, and inhibited phagocytosis. DRAIR regulated target gene expression through interaction with chromatin, and inhibition of the repressive epigenetic mark H3K9me2 and its corresponding methyltransferase G9a. Mouse orthologous Drair and Cpeb2 were also downregulated in peritoneal macrophages from T2D db/db mice, and Drair knockdown in non-diabetic mice enhanced pro-inflammatory genes in macrophages. Thus, DRAIR modulates inflammatory phenotype of monocytes/macrophages via epigenetic mechanisms, and its downregulation in T2D may promote chronic inflammation. Augmentation of endogenous lncRNAs like DRAIR could serve as novel anti-inflammatory therapies for diabetic complications.
Marpadga A. Reddy, Vishnu Amaram, Sadhan Das, Vinay Singh Tanwar, Rituparna Ganguly, Mei Wang, Linda Lanting, Linxiao Zhang, Maryam Abdollahi, Zhuo Chen, Xiwei Wu, Sridevi Devaraj, Rama Natarajan
Clinical phenotyping of term and preterm labor is imprecise, and disagreement persists on categorization relative to underlying pathobiology, which remains poorly understood. We performed RNA sequencing (RNA-seq) of 31 specimens of human uterine myometrium from 10 term and 21 preterm cesarean deliveries with rich clinical context information. A molecular signature of 4,814 transcripts stratified myometrial samples into quiescent (Q) and non-quiescent (NQ) phenotypes, independent of gestational age and incision site. Similar stratifications were achieved using expressed genes in Ca2+ signaling and TGF-β pathways. For maximal parsimony, we evaluated the expression of just two Ca2+ transporter genes, ATP2B4 (encoding PMCA4) and ATP2A2 (coding for SERCA2), and found that their ratio reliably distinguished NQ and Q specimens in the current study, and also in two publically available RNA-seq datasets (GSE50599 and GSE80172), with an overall AUC of 0.94. Cross-validation of the ATP2B4/ATP2A2 ratio by qPCR in an expanded cohort (by 11 additional specimens) achieved complete separation (AUC=1.00) of NQ vs. Q specimens. While providing additional insight into the associations between clinical features of term and preterm labor and myometrial gene expression, our study also offers a practical algorithm for unbiased classification of myometrial biopsies by their overall contractile program.
William E. Ackerman IV, Catalin S. Buhimschi, Ali Snedden, Taryn L. Summerfield, Guomao Zhao, Irina A. Buhimschi
The epithelial cell-derived cytokines IL-25, IL-33 and TSLP initiate type 2 inflammation in allergic diseases including asthma. However, the signaling pathway regulating these cytokines expression remains elusive. Since microRNAs are pivotal regulators of gene expression, we profiled microRNA expression in bronchial epithelial brushings from type 2-low and type 2-high asthma patients. MiR-206 was the most highly expressed epithelial microRNA in type 2-high asthma relative to type 2-low asthma but was downregulated in both subsets compared with healthy controls. CD39, an ectonucleotidase degrading ATP, was a target of miR-206 and upregulated in asthma. Allergen-induced acute extracellular ATP accumulation led to miR-206 downregulation and CD39 upregulation in human bronchial epithelial cells, forming a feedback loop to eliminate excessive ATP. Airway ATP levels were markedly elevated and strongly correlated with IL-25 and TSLP expression in asthma patients. Intriguingly, airway miR-206 antagonism increased Cd39 expression, reduced ATP accumulation, suppressed Il-25, Il-33, Tslp expression and group 2 innate lymphoid cell expansion, and alleviated type 2 inflammation in a mouse model of allergic airway inflammation. In contrast, airway miR-206 overexpression had opposite effects. Overall, epithelial miR-206 upregulates airway IL-25, TSLP expression by targeting CD39-extracellular ATP axis, which represents a novel therapeutic target in type 2-high asthma.
Kan Zhang, Yuchen Feng, Yuxia Liang, Wenliang Wu, Chenli Chang, Dian Chen, Shengchong Chen, Jiali Gao, Gongqi Chen, Lingling Yi, Dan Cheng, Guohua Zhen
Similar to tumor initiating cells (TICs), minimal residual disease (MRD) is capable of re-initiating tumors and causing recurrence. However, the molecular characteristics of solid tumor MRD cells and drivers of their survival have remained elusive. Here we performed dense multi-region transcriptomics analysis of paired biopsies from 17 ovarian cancer patients before and after chemotherapy. We reveal that while MRD cells share important molecular signatures with TICs, they are also characterized by an adipocyte-like gene expression signature and a portion of them had undergone epithelial-mesenchymal transition (EMT). In a cell culture MRD model, MRD-mimic cells show the same phenotype and are dependent on fatty acid oxidation for survival and resistance to cytotoxic agents. These findings identify EMT and FAO as attractive targets to eradicate MRD in ovarian cancer and make a compelling case for the further testing of FAO inhibitors in treating MRD.
Mara Artibani, Kenta Masuda, Zhiyuan Hu, Pascal C. Rauher, Garry Mallett, Nina Wietek, Matteo Morotti, Kay Chong, Mohammad KaramiNejadRanjbar, Christos E. Zois, Sunanda Dhar, Salma El-Sahhar, Leticia Campo, Sarah P. Blagden, Stephen Damato, Pubudu N. Pathiraja, Shibani Nicum, Fergus Gleeson, Alexandros Laios, Abdulkhaliq Alsaadi, Laura Santana Gonzalez, Takeshi Motohara, Ashwag Albukhari, Zhen Lu, Robert C. Bast Jr., Adrian L. Harris, Christer S. Ejsing, Robin W. Klemm, Christopher Yau, Tatjana Sauka-Spengler, Ahmed A. Ahmed
Complete absence of thyroid hormone is incompatible with life in vertebrates. Thyroxine is synthesized within thyroid follicles upon iodination of thyroglobulin conveyed from the endoplasmic reticulum (ER), via the Golgi complex, to the extracellular follicular lumen. In congenital hypothyroidism from bi-allelic thyroglobulin mutation, thyroglobulin is misfolded and cannot advance from the ER, eliminating its secretion and triggering ER stress. Nevertheless, untreated patients somehow continue to synthesize sufficient thyroxine to yield measurable serum levels that sustain life. We demonstrate that TGW2346R/ W2346R humans, TGcog/cog mice, and TGrdw/rdw rats exhibit no detectable ER export of thyroglobulin, accompanied by severe thyroidal ER stress and thyroid cell death. Nevertheless, thyroxine is synthesized and brief treatment of TGrdw/rdw rats with anti-thyroid drug is lethal to the animals. When untreated, remarkably, thyroxine is synthesized on the mutant thyroglobulin protein, delivered via dead thyrocytes that decompose within the follicle lumen, where they are iodinated and cannabilized by surrounding live thyrocytes. As long as the animals grow a goiter, circulating thyroxine increases. However, when TGrdw/rdw rats age, they cannot sustain goiter growth that provides the dying cells needed for ongoing thyroxine synthesis, resulting in profound hypothyroidism. These results establish a disease mechanism wherein dead thyrocytes support organismal survival.
Xiaohan Zhang, Aaron P. Kellogg, Cintia E. Citterio, Hao Zhang, Dennis Larkin, Yoshiaki Morishita, Hector M. Targovnik, Viviana A. Balbi, Peter Arvan
BACKGROUND. Little is known about pathogen-specific humoral immunity in individuals with long-term remission after treatment with chimeric antigen receptor-modified T-cells (CAR-T-cells) for B-cell lineage malignancies. METHODS. We conducted a prospective cross-sectional study of CD19-targeted or BCMA-targeted CAR-T-cell therapy recipients ≥6 months post-treatment and in remission. We measured lymphocyte subsets, immunoglobulins, pathogen-specific IgG for 12 vaccine-preventable infections, and the total number of viral and bacterial epitopes to which IgG was detected (‘epitope hits’) using a serological profiling assay. The primary outcome was the proportion of participants with IgG levels above a threshold correlated with seroprotection for vaccine-preventable infections. RESULTS. We enrolled 65 children and adults a median of 20 months after CD19- (n=54) or BCMA- (n=11) CAR-T-cell therapy. Among 30 adults without IgG replacement therapy (IGRT) in the prior 16 weeks, 27 (90%) had hypogammaglobulinemia. Despite this, these individuals had seroprotection to a median of 67% (IQR, 59-73%) of tested vaccine-preventable infections. Proportions of participants with seroprotection per-pathogen were comparable to population-based studies, but most individuals lacked seroprotection to specific pathogens. Compared to CD19-CAR-T-cell recipients, BCMA-CAR-T-cell recipients were half as likely to have seroprotection to vaccine-preventable infections (prevalence ratio, 0.47; 95% CI, 0.18-1.25) and had fewer pathogen-specific epitope hits (mean difference, -90 epitope hits; 95% CI, -157 to -22). CONCLUSIONS. Seroprotection for vaccine-preventable infections in adult CD19-CAR-T-cell recipients was comparable to the general population, but BCMA-CAR-T-cell recipients have fewer pathogen-specific antibodies. Deficits in both groups support the need for randomized vaccine and IGRT trials to determine efficacy and risk-benefit.
Carla S. Walti, Elizabeth M. Krantz, Joyce Maalouf, Jim Boonyaratanakornkit, Jacob Keane-Candib, Laurel Joncas-Schronce, Terry Stevens-Ayers, Sayan Dasgupta, Justin J. Taylor, Alexandre V. Hirayama, Merav Bar, Rebecca A. Gardner, Andrew J. Cowan, Damian J. Green, Michael J. Boeckh, David G. Maloney, Cameron J. Turtle, Joshua A. Hill
Patients with chronic kidney disease (CKD) and end stage renal disease suffer from increased cardiovascular events and cardiac mortality. Prior studies have demonstrated a portion of this enhanced risk can be attributed to the accumulation of microbiota-derived toxic metabolites, with most studies focusing on the sulfonated form of p-cresol (PCS). However, unconjugated p-cresol (uPC) itself was never assessed due to rapid and extensive first pass metabolism that results in negligible serum concentrations of uPC. These reports thus failed to consider the host exposure to uPC prior to hepatic metabolism. In the current study, we not only measured the impact of altering the intestinal microbiota on lipid accumulation in coronary arteries, but also examined macrophage lipid uptake and handling pathways in response to uPC. We found atherosclerotic-prone mice fed a high fat diet exhibited significantly higher coronary artery lipid deposits upon receiving fecal material from CKD mice. Furthermore, treatment with uPC increased total cholesterol, triglycerides, hepatic, and aortic fatty deposits in non-CKD mice. Studies employing an in vitro macrophage model demonstrated uPC exposure increased apoptosis where PCS did not. Additionally, uPC exhibited higher potency than PCS to stimulate low density lipoprotein (LDL) uptake and only uPC induced endocytosis and pinocytosis-related genes. Pharmacological inhibition of varying cholesterol influx and efflux systems indicated that uPC increased macrophage LDL uptake by activating macropinocytosis. Overall, these findings indicate uPC itself has a distinct impact on macrophage biology that may contribute to increased cardiovascular risk in patients with CKD.
Lee D. Chaves, Sham Abyad, Amanda M. Honan, Mark A. Bryniarski, Daniel I. McSkimming, Corrine M. Stahura, Steven C. Wells, Donna M. Ruszaj, Marilyn E. Morris, Richard J. Quigg, Rabi Yacoub
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