Intravital imaging reveals glomerular capillary distension and endothelial cell activation in Alport syndrome
Gyarmati et al. identify the central roles of glomerular mechanical forces as well as endothelial and immune cell activation early in Alport syndrome. The cover image shows intravital multiphoton microscopy imaging of immune cell features in a late-stage Alport syndrome model.
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Research Articles
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Abstract
While current thinking posits that insulin signaling to glucose transporter 4 (GLUT4) exocytic translocation and glucose uptake in skeletal muscle and adipocytes is controlled by phosphorylation-based signaling, many proteins in this pathway are acetylated on lysine residues. However, the importance of acetylation and lysine acetyltransferases to insulin-stimulated glucose uptake is incompletely defined. Here, we demonstrate that combined loss of the acetyltransferases E1A binding protein p300 (p300) and cAMP response element binding protein binding protein (CBP) in mouse skeletal muscle caused a complete loss of insulin-stimulated glucose uptake. Similarly, brief (i.e., 1 hour) pharmacological inhibition of p300/CBP acetyltransferase activity recapitulated this phenotype in human and rodent myotubes, 3T3-L1 adipocytes, and mouse muscle. Mechanistically, these effects were due to p300/CBP-mediated regulation of GLUT4 exocytic translocation and occurred downstream of Akt signaling. Taken together, we highlight a fundamental role for acetylation and p300/CBP in the direct regulation of insulin-stimulated glucose transport in skeletal muscle and adipocytes.
Authors
Vitor F. Martins, Samuel A. LaBarge, Alexandra Stanley, Kristoffer Svensson, Chao-Wei Hung, Omer Keinan, Theodore P. Ciaraldi, Dion Banoian, Ji E. Park, Christina Ha, Byron Hetrick, Gretchen A. Meyer, Andrew Philp, Larry L. David, Robert R. Henry, Joseph E. Aslan, Alan R. Saltiel, Carrie. E. McCurdy, Simon Schenk
×Abstract
Nonphlogistic migration of macrophages contributes to the clearance of pathogens and apoptotic cells, a critical step for the resolution of inflammation and return to homeostasis. Angiotensin-(1-7) [Ang-(1-7)] is a heptapeptide of the renin-angiotensin system that acts through Mas receptor (MasR). Ang-(1-7) has recently emerged as a novel proresolving mediator, yet Ang-(1-7) resolution mechanisms are not fully determined. Herein, Ang-(1-7) stimulated migration of human and murine monocytes/macrophages in a MasR-, CCR2-, and MEK/ERK1/2–dependent manner. Pleural injection of Ang-(1-7) promoted nonphlogistic mononuclear cell influx alongside increased levels of CCL2, IL-10, and macrophage polarization toward a regulatory phenotype. Ang-(1-7) induction of CCL2 and mononuclear cell migration was also dependent on MasR and MEK/ERK. Of note, MasR was upregulated during the resolution phase of inflammation, and its pharmacological inhibition or genetic deficiency impaired mononuclear cell recruitment during self-resolving models of LPS pleurisy and E. coli peritonitis. Inhibition/absence of MasR was associated with reduced CCL2 levels, impaired phagocytosis of bacteria, efferocytosis, and delayed resolution of inflammation. In summary, we have uncovered a potentially novel proresolving feature of Ang-(1-7), namely the recruitment of mononuclear cells favoring efferocytosis, phagocytosis, and resolution of inflammation. Mechanistically, cell migration was dependent on MasR, CCR2, and the MEK/ERK pathway.
Authors
Isabella Zaidan, Luciana P. Tavares, Michelle A. Sugimoto, Kátia M. Lima, Graziele L. Negreiros-Lima, Lívia C.R. Teixeira, Thais C. Miranda, Bruno V.S. Valiate, Allysson Cramer, Juliana Priscila Vago, Gabriel H. Campolina-Silva, Jéssica A.M. Souza, Laís C. Grossi, Vanessa Pinho, Maria Jose Campagnole-Santos, Robson A.S. Santos, Mauro M. Teixeira, Izabela Galvão, Lirlândia P. Sousa
×Abstract
Accumulating evidence has shown that cancer stroma and BM-derived cells (BMDCs) in the tumor microenvironment (TME) play vital roles in tumor progression. However, the mechanism by which oral cancer stroma recruits any particular subset of BMDCs remains largely unknown. Here, we sought to identify the subset of BMDCs that is recruited by cancer stroma. We established a sequential transplantation model in BALB/c nude mice, including (a) BM transplantation of GFP-expressing cells and (b) coxenografting of patient-derived stroma (PDS; 2 cases, designated PDS1 and PDS2) with oral cancer cells (HSC-2). As controls, xenografting was performed with HSC-2 alone or in combination with normal human dermal fibroblasts (HDF). PDS1, PDS2, and HDF all promoted BMDC migration in vitro and recruitment in vivo. Multicolor immunofluorescence revealed that the PDS coxenografts recruited Arginase-1+CD11b+GR1+GFP+ cells, which are myeloid-derived suppressor cells (MDSCs), to the TME, whereas the HDF coxenograft did not. Screening using microarrays revealed that PDS1 and PDS2 expressed CCL2 mRNA (encoding C-C motif chemokine ligand 2) at higher levels than did HDF. Indeed, PDS xenografts contained significantly higher proportions of CCL2+ stromal cells and CCR2+Arginase-1+CD11b+GR1+ MDSCs (as receiver cells) than the HDF coxenograft. Consistently, a CCL2 synthesis inhibitor and a CCR2 antagonist significantly inhibited the PDS-driven migration of BM cells in vitro. Furthermore, i.p. injection of the CCR2 antagonist to the PDS xenograft models significantly reduced the CCR2+Arginase-1+CD11b+GR1+ MDSC infiltration to the TME. In conclusion, oral cancer stroma–secreted CCL2 is a key signal for recruiting CCR2+ MDSCs from BM to the TME.
Authors
May Wathone Oo, Hotaka Kawai, Kiyofumi Takabatake, Shuta Tomida, Takanori Eguchi, Kisho Ono, Qiusheng Shan, Toshiaki Ohara, Saori Yoshida, Haruka Omori, Shintaro Sukegawa, Keisuke Nakano, Kuniaki Okamoto, Akira Sasaki, Hitoshi Nagatsuka
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SNHG12, a long noncoding RNA (lncRNA) dysregulated in atherosclerosis, is known to be a key regulator of vascular senescence in endothelial cells (ECs). However, its role in angiogenesis and peripheral artery disease has not been elucidated. Hind-limb ischemia studies using femoral artery ligation (FAL) in mice showed that SNHG12 expression falls readily in the acute phase of the response to limb ischemia in gastrocnemius muscle and recovers to normal when blood flow recovery is restored to ischemic muscle, indicating that it likely plays a role in the angiogenic response to ischemia. Gain- and loss-of-function studies demonstrated that SNHG12 regulated angiogenesis — SNHG12 deficiency reduced cell proliferation, migration, and endothelial sprouting, whereas overexpression promoted these angiogenic functions. We identified SNHG12 binding partners by proteomics that may contribute to its role in angiogenesis, including IGF-2 mRNA–binding protein 3 (IGF2BP3, also known as IMP3). RNA-Seq profiling of SNHG12-deficient ECs showed effects on angiogenesis pathways and identified a strong effect on cell cycle regulation, which may be modulated by IMP3. Knockdown of SNHG12 in mice undergoing FAL using injected gapmeRs) decreased angiogenesis, an effect that was more pronounced in a model of insulin-resistant db/db mice. RNA-Seq profiling of the EC and non-EC compartments in these mice revealed a likely role of SNHG12 knockdown on Wnt, Notch, and angiopoietin signaling pathways. Together, these findings indicate that SNHG12 plays an important role in the angiogenic EC response to ischemia.
Authors
David A. Gross, Henry S. Cheng, Rulin Zhuang, Michael G. McCoy, Daniel Pérez-Cremades, Zachary Salyers, A.K.M. Khyrul Wara, Stefan Haemmig, Terence E. Ryan, Mark W. Feinberg
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Identification and analysis of fungal communities commonly rely on internal transcribed spacer–based (ITS-based) amplicon sequencing. There is no gold standard used to infer and classify fungal constituents since methodologies have been adapted from analyses of bacterial communities. To achieve high-resolution inference of fungal constituents, we customized a DADA2-based pipeline using a mix of 11 medically relevant fungi. While DADA2 allowed the discrimination of ITS1 sequences differing by single nucleotides, quality filtering, sequencing bias, and database selection were identified as key variables determining the accuracy of sample inference. Due to species-specific differences in sequencing quality, default filtering settings removed most reads that originated from Aspergillus species, Saccharomyces cerevisiae, and Candida glabrata. By fine-tuning the quality filtering process, we achieved an improved representation of the fungal communities. By adapting a wobble nucleotide in the ITS1 forward primer region, we further increased the yield of S. cerevisiae and C. glabrata sequences. Finally, we showed that a BLAST-based algorithm based on the UNITE+INSD or the NCBI NT database achieved a higher reliability in species-level taxonomic annotation compared with the naive Bayesian classifier implemented in DADA2. These steps optimized a robust fungal ITS1 sequencing pipeline that, in most instances, enabled species-level assignment of community members.
Authors
Thierry Rolling, Bing Zhai, John Frame, Tobias M. Hohl, Ying Taur
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The protein tau and its isoforms are associated with several neurodegenerative diseases, many of which are characterized by greater deposition of the 4-repeat (4R) tau isoform; however, the role of 4R tau in disease pathogenesis remains unclear. We created antisense oligonucleotides (ASOs) that alter the ratio of 3R to 4R tau to investigate the role of specific tau isoforms in disease. Preferential expression of 4R tau in human tau–expressing (hTau-expressing) mice was previously shown to increase seizure severity and phosphorylated tau deposition without neuronal or synaptic loss. In this study, we observed strong colocalization of 4R tau within reactive astrocytes and increased expression of pan-reactive and neurotoxic genes following 3R to 4R tau splicing ASO treatment in hTau mice. Increasing 4R tau levels in primary astrocytes provoked a similar response, including a neurotoxic genetic profile and diminished homeostatic function, which was replicated in human induced pluripotent stem cell–derived (iPSC-derived) astrocytes harboring a mutation that exhibits greater 4R tau. Healthy neurons cultured with 4R tau–expressing human iPSC–derived astrocytes exhibited a higher firing frequency and hypersynchrony, which could be prevented by lowering tau expression. These findings support a potentially novel pathway by which astrocytic 4R tau mediates reactivity and dysfunction and suggest that astrocyte-targeted therapeutics against 4R tau may mitigate neurodegenerative disease progression.
Authors
Lubov A. Ezerskiy, Kathleen M. Schoch, Chihiro Sato, Mariana Beltcheva, Kanta Horie, Frank Rigo, Ryan Martynowicz, Celeste M. Karch, Randall J. Bateman, Timothy M. Miller
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Congenital cytomegalovirus (cCMV) infection is the leading infectious cause of neurodevelopmental disorders. However, the neuropathogenesis remains largely elusive due to a lack of informative animal models. In this study, we developed a congenital murine CMV (cMCMV) infection mouse model with high survival rate and long survival period that allowed long-term follow-up study of neurodevelopmental disorders. This model involves in utero intracranial injection and mimics many reported clinical manifestations of cCMV infection in infants, including growth restriction, hearing loss, and impaired cognitive and learning-memory abilities. We observed that abnormalities in MRI/CT neuroimaging were consistent with brain hemorrhage and loss of brain parenchyma, which was confirmed by pathological analysis. Neuropathological findings included ventriculomegaly and cortical atrophy associated with impaired proliferation and migration of neural progenitor cells in the developing brain at both embryonic and postnatal stages. Robust inflammatory responses during infection were shown by elevated inflammatory cytokine levels, leukocyte infiltration, and activation of microglia and astrocytes in the brain. Pathological analyses and CT neuroimaging revealed brain calcifications induced by cMCMV infection and cell death via pyroptosis. Furthermore, antiviral treatment with ganciclovir significantly improved neurological functions and mitigated brain damage as shown by CT neuroimaging. These results demonstrate that this model is suitable for investigation of mechanisms of infection-induced brain damage and long-term studies of neurodevelopmental disorders, including the development of interventions to limit CNS damage associated with cCMV infection.
Authors
Yue-Peng Zhou, Meng-Jie Mei, Xian-Zhang Wang, Sheng-Nan Huang, Lin Chen, Ming Zhang, Xin-Yan Li, Hai-Bin Qin, Xiao Dong, Shuang Cheng, Le Wen, Bo Yang, Xue-Fang An, Ao-Di He, Bing Zhang, Wen-Bo Zeng, Xiao-Jun Li, Youming Lu, Hong-Chuang Li, Haidong Li, Wei-Guo Zou, Alec J. Redwood, Simon Rayner, Han Cheng, Michael A. McVoy, Qiyi Tang, William J. Britt, Xin Zhou, Xuan Jiang, Min-Hua Luo
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BACKGROUND RBC transfusion effectiveness varies due to donor, component, and recipient factors. Prior studies identified characteristics associated with variation in hemoglobin increments following transfusion. We extended these observations, examining donor genetic and nongenetic factors affecting transfusion effectiveness.METHODS This is a multicenter retrospective study of 46,705 patients and 102,043 evaluable RBC transfusions from 2013 to 2016 across 12 hospitals. Transfusion effectiveness was defined as hemoglobin, bilirubin, or creatinine increments following single RBC unit transfusion. Models incorporated a subset of donors with data on single nucleotide polymorphisms associated with osmotic and oxidative hemolysis in vitro. Mixed modeling accounting for repeated transfusion episodes identified predictors of transfusion effectiveness.RESULTS Blood donor (sex, Rh status, fingerstick hemoglobin, smoking), component (storage duration, γ irradiation, leukoreduction, apheresis collection, storage solution), and recipient (sex, BMI, race and ethnicity, age) characteristics were associated with hemoglobin and bilirubin, but not creatinine, increments following RBC transfusions. Increased storage duration was associated with increased bilirubin and decreased hemoglobin increments, suggestive of in vivo hemolysis following transfusion. Donor G6PD deficiency and polymorphisms in SEC14L4, HBA2, and MYO9B genes were associated with decreased hemoglobin increments. Donor G6PD deficiency and polymorphisms in SEC14L4 were associated with increased transfusion requirements in the subsequent 48 hours.CONCLUSION Donor genetic and other factors, such as RBC storage duration, affect transfusion effectiveness as defined by decreased hemoglobin or increased bilirubin increments. Addressing these factors will provide a precision medicine approach to improve patient outcomes, particularly for chronically transfused RBC recipients, who would most benefit from more effective transfusion products.FUNDING Funding was provided by HHSN 75N92019D00032, HHSN 75N92019D00034, 75N92019D00035, HHSN 75N92019D00036, and HHSN 75N92019D00037; R01HL126130; and the National Institute of Child Health and Human Development (NICHD).
Authors
Nareg H. Roubinian, Sarah E. Reese, Hannah Qiao, Colleen Plimier, Fang Fang, Grier P. Page, Ritchard G. Cable, Brian Custer, Mark T. Gladwin, Ruchika Goel, Bob Harris, Jeanne E. Hendrickson, Tamir Kanias, Steve Kleinman, Alan E. Mast, Steven R. Sloan, Bryan R. Spencer, Steven L. Spitalnik, Michael P. Busch, Eldad A. Hod, on behalf of the National Heart Lung and Blood Institute (NHLBI) Recipient Epidemiology and Donor Evaluation Study IV Pediatrics (REDS-IV-P)
×Abstract
Colorectal cancers (CRCs) exhibit differences in incidence, pathogenesis, molecular pathways, and outcome depending on the location of the tumor. The transcriptomes of 27,927 single human CRC cells from 3 left-sided and 3 right-sided CRC patients were profiled by single-cell RNA-Seq (scRNA-Seq). Right-sided CRC harbors a significant proportion of exhausted CD8+ T cells of a highly migratory nature. One cluster of cells from left-sided CRC exhibiting states preceding exhaustion and a high ratio of preexhausted/exhausted T cells were favorable prognostic markers. Notably, we identified a potentially novel RBP4+NTS+ subpopulation of cancer cells that exclusively expands in left-sided CRC. Tregs from left-sided CRC showed higher levels of immunotherapy-related genes than those from right-sided CRC, indicating that left-sided CRC may have increased responsiveness to immunotherapy. Antibody-dependent cellular phagocytosis (ADCP) and antibody-dependent cellular cytotoxicity (ADCC) induced by M2-like macrophages were more pronounced in left-sided CRC and correlated with a good prognosis in CRC.
Authors
Wei Guo, Cuiyu Zhang, Xia Wang, Dandan Dou, Dawei Chen, Jingxin Li
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Herein, we characterize the landscape and prognostic significance of the T cell receptor (TCR) repertoire of early-stage non–small cell lung cancer (NSCLC) for patients with an epidermal growth factor receptor (EGFR) mutation. β Chain TCR sequencing was used to characterize the TCR repertoires of paraffin-preserved pretreatment tumor and tumor-adjacent tissues from 57 and 44 patients with stage II/III NSCLC with an EGFR mutation treated with gefitinib or chemotherapy in the ADJUVANT-CTONG 1104 trial. The TCR diversity was significantly decreased in patients with an EGFR mutation, and patients with high TCR diversity had a favorable overall survival (OS). A total of 10 TCR Vβ-Jβ rearrangements were significantly associated with OS. Patients with a higher frequency of Vβ5-6Jβ2-1, Vβ20-1Jβ2-1, Vβ24-1Jβ2-1, and Vβ29-1Jβ2-7 had significantly longer OS. Weighted combinations of the 4 TCRs were significantly associated with OS and disease-free survival (DFS) of patients, which could further stratify the high and low TCR diversity groups. Importantly, Vβ5-6Jβ2-1, Vβ20-1Jβ2-1, and Vβ24-1Jβ2-1 had a significant relationship with gefitinib treatment, while Vβ29-1Jβ2-7 was associated with chemotherapy. Four TCR Vβ-Jβ rearrangements related to favorable OS and DFS for adjuvant gefitinib and chemotherapy in patients with an EGFR mutation with stage II/III NSCLC; this may provide a novel perspective for the adjuvant setting for resectable NSCLC.
Authors
Cunte Chen, Si-Yang Maggie Liu, Yedan Chen, Qiuxiang Ou, Hua Bao, Ling Xu, Yikai Zhang, Wenzhao Zhong, Qing Zhou, Xue-Ning Yang, Yang Shao, Yi-Long Wu, Si-Yang Liu, Yangqiu Li
×Abstract
Alport syndrome (AS) is a genetic disorder caused by mutations in type IV collagen that lead to defective glomerular basement membrane, glomerular filtration barrier (GFB) damage, and progressive chronic kidney disease. While the genetic basis of AS is well known, the molecular and cellular mechanistic details of disease pathogenesis have been elusive, hindering the development of mechanism-based therapies. Here, we performed intravital multiphoton imaging of the local kidney tissue microenvironment in a X-linked AS mouse model to directly visualize the major drivers of AS pathology. Severely distended glomerular capillaries and aneurysms were found accompanied by numerous microthrombi, increased glomerular endothelial surface layer (glycocalyx) and immune cell homing, GFB albumin leakage, glomerulosclerosis, and interstitial fibrosis by 5 months of age, with an intermediate phenotype at 2 months. Renal histology in mouse or patient tissues largely failed to detect capillary aberrations. Treatment of AS mice with hyaluronidase or the ACE inhibitor enalapril reduced the excess glomerular endothelial glycocalyx and blocked immune cell homing and GFB albumin leakage. This study identified central roles of glomerular mechanical forces and endothelial and immune cell activation early in AS, which could be therapeutically targeted to reduce mechanical strain and local tissue inflammation and improve kidney function.
Authors
Georgina Gyarmati, Urvi Nikhil Shroff, Audrey Izuhara, Xiaogang Hou, Stefano Da Sacco, Sargis Sedrakyan, Kevin V. Lemley, Kerstin Amann, Laura Perin, János Peti-Peterdi
×Abstract
The biosynthetic routes leading to de novo nicotinamide adenine dinucleotide (NAD+) production are involved in acute kidney injury (AKI), with a critical role for quinolinate phosphoribosyl transferase (QPRT), a bottleneck enzyme of de novo NAD+ biosynthesis. The molecular mechanisms determining reduced QPRT in AKI, and the role of impaired NAD+ biosynthesis in the progression to chronic kidney disease (CKD), are unknown. We demonstrate that a high urinary quinolinate-to-tryptophan ratio, an indirect indicator of impaired QPRT activity and reduced de novo NAD+ biosynthesis in the kidney, is a clinically applicable early marker of AKI after cardiac surgery and is predictive of progression to CKD in kidney transplant recipients. We also provide evidence that the endoplasmic reticulum (ER) stress response may impair de novo NAD+ biosynthesis by repressing QPRT transcription. In conclusion, NAD+ biosynthesis impairment is an early event in AKI embedded with the ER stress response, and persistent reduction of QPRT expression is associated with AKI to CKD progression. This finding may lead to identification of noninvasive metabolic biomarkers of kidney injury with prognostic and therapeutic implications.
Authors
Yohan Bignon, Anna Rinaldi, Zahia Nadour, Virginie Poindessous, Ivan Nemazanyy, Olivia Lenoir, Baptiste Fohlen, Pierre Weill-Raynal, Alexandre Hertig, Alexandre Karras, Pierre Galichon, Maarten Naesens, Dany Anglicheau, Pietro E. Cippà, Nicolas Pallet
×Abstract
Sangivamycin is a nucleoside analog that is well tolerated by humans and broadly active against phylogenetically distinct viruses, including arenaviruses, filoviruses, and orthopoxviruses. Here, we show that sangivamycin is a potent antiviral against multiple variants of replicative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with half-maximal inhibitory concentration in the nanomolar range in several cell types. Sangivamycin suppressed SARS-CoV-2 replication with greater efficacy than remdesivir (another broad-spectrum nucleoside analog). When we investigated sangivamycin’s potential for clinical administration, pharmacokinetic; absorption, distribution, metabolism, and excretion (ADME); and toxicity properties were found to be favorable. When tested in combination with remdesivir, efficacy was additive rather than competitive against SARS-CoV-2. The proven safety in humans, long half-life, potent antiviral activity (compared to remdesivir), and combinatorial potential suggest that sangivamycin is likely to be efficacious alone or in combination therapy to suppress viremia in patients. Sangivamycin may also have the ability to help combat drug-resistant or vaccine-escaping SARS-CoV-2 variants since it is antivirally active against several tested variants. Our results support the pursuit of sangivamycin for further preclinical and clinical development as a potential coronavirus disease 2019 therapeutic.
Authors
Ryan P. Bennett, Elena N. Postnikova, Brett P. Eaton, Yingyun Cai, Shuiqing Yu, Charles O. Smith, Janie Liang, Huanying Zhou, Gregory A. Kocher, Michael J. Murphy, Harold C. Smith, Jens H. Kuhn
×Abstract
Immune checkpoint therapy targeting the PD-1/PD-L1 axis is a potentially novel development in anticancer therapy and has been applied to clinical medicine. However, there are still some problems, including a relatively low response rate, innate mechanisms of resistance against immune checkpoint blockades, and the absence of reliable biomarkers to predict responsiveness. In this study of in vitro and in vivo models, we demonstrate that PD-L1–vInt4, a splicing variant of PD-L1, plays a role as a decoy in anti–PD-L1 antibody treatment. First, we showed that PD-L1–vInt4 was detectable in clinical samples and that it was possible to visualize the secreting variants with IHC. By overexpressing the PD-L1–secreted splicing variant on MC38 cells, we observed that an immune-suppressing effect was not induced by their secretion alone. We then demonstrated that PD-L1–vInt4 secretion resisted anti–PD-L1 antibody treatment, compared with WT PD-L1, which was explicable by the PD-L1–vInt4’s decoying of the anti–PD-L1 antibody. The decoying function of PD-L1 splicing variants may be one of the reasons for cancers being resistant to anti–PD-L1 therapy. Measuring serum PD-L1 levels might be helpful in deciding the therapeutic strategy.
Authors
Ray Sagawa, Seiji Sakata, Bo Gong, Yosuke Seto, Ai Takemoto, Satoshi Takagi, Hironori Ninomiya, Noriko Yanagitani, Masayuki Nakao, Mingyon Mun, Ken Uchibori, Makoto Nishio, Yasunari Miyazaki, Yuichi Shiraishi, Seishi Ogawa, Keisuke Kataoka, Naoya Fujita, Kengo Takeuchi, Ryohei Katayama
×Abstract
A fibrotic stroma accumulates in advanced cancers, and invasive cancer cells migrate along collagen fibers that facilitate dissemination from the primary tumor. However, the ways in which tumor cells govern these processes remain unclear. Here, we report that the epithelial-mesenchymal transition–activating transcription factor ZEB1 increased type I collagen (Col1) secretion and enhanced tumor cell adherence to Col1. Mechanistically, ZEB1 increased the levels of α1β1 integrin (encoded by Itga1 and Itgb1) by inhibiting PP2A activity, which reduced nuclear accumulation of HDAC4 and, thereby, derepressed Itga1 gene transcription. In parallel, ZEB1 relieved the miRNA-148a-mediated silencing of Itga1. High levels of Itga1 enhanced tumor cell adherence to Col1 and were essential for Col1-induced tumor growth and metastasis. Furthermore, ZEB1 enhanced Col1 secretion by increasing the expression of a kinesin protein that facilitated transport and secretion of Col1-containing vesicles. Our findings elucidate a transcriptional mechanism by which lung adenocarcinoma cells coordinate a collagen deposition and adhesion process that facilitates tumor progression.
Authors
Xiaochao Tan, Priyam Banerjee, Xin Liu, Jiang Yu, Sieun Lee, Young-Ho Ahn, Chad J. Creighton, Jonathan M. Kurie
×Abstract
Tools for noninvasive detection of bacterial pathogens are needed but are not currently available for clinical use. We have previously shown that para-aminobenzoic acid (PABA) rapidly accumulates in a wide range of pathogenic bacteria, motivating the development of related PET radiotracers. In this study, 11C-PABA PET imaging was used to accurately detect and monitor infections due to pyogenic bacteria in multiple clinically relevant animal models. 11C-PABA PET imaging selectively detected infections in muscle, intervertebral discs, and methicillin-resistant Staphylococcus aureus–infected orthopedic implants. In what we believe to be first-in-human studies in healthy participants, 11C-PABA was safe, well-tolerated, and had a favorable biodistribution, with low background activity in the lungs, muscles, and brain. 11C-PABA has the potential for clinical translation to detect and localize a broad range of bacteria.
Authors
Alvaro A. Ordonez, Matthew F.L. Parker, Robert J. Miller, Donika Plyku, Camilo A. Ruiz-Bedoya, Elizabeth W. Tucker, Justin M. Luu, Dustin A. Dikeman, Wojciech G. Lesniak, Daniel P. Holt, Robert F. Dannals, Lloyd S. Miller, Steven P. Rowe, David M. Wilson, Sanjay K. Jain
×Abstract
Neutrophils are recognized as important circulating effector cells in the pathophysiology of severe coronavirus disease 2019 (COVID-19). However, their role within the inflamed lungs is incompletely understood. Here, we collected bronchoalveolar lavage (BAL) fluids and parallel blood samples of critically ill COVID-19 patients requiring invasive mechanical ventilation and compared BAL fluid parameters with those of mechanically ventilated patients with influenza, as a non–COVID-19 viral pneumonia cohort. Compared with those of patients with influenza, BAL fluids of patients with COVID-19 contained increased numbers of hyperactivated degranulating neutrophils and elevated concentrations of the cytokines IL-1β, IL-1RA, IL-17A, TNF-α, and G-CSF; the chemokines CCL7, CXCL1, CXCL8, CXCL11, and CXCL12α; and the protease inhibitors elafin, secretory leukocyte protease inhibitor, and tissue inhibitor of metalloproteinases 1. In contrast, α-1 antitrypsin levels and net proteolytic activity were comparable in COVID-19 and influenza BAL fluids. During antibiotic treatment for bacterial coinfections, increased BAL fluid levels of several activating and chemotactic factors for monocytes, lymphocytes, and NK cells were detected in patients with COVID-19 whereas concentrations tended to decrease in patients with influenza, highlighting the persistent immunological response to coinfections in COVID-19. Finally, the high proteolytic activity in COVID-19 lungs suggests considering protease inhibitors as a treatment option.
Authors
Seppe Cambier, Mieke Metzemaekers, Ana Carolina de Carvalho, Amber Nooyens, Cato Jacobs, Lore Vanderbeke, Bert Malengier-Devlies, Mieke Gouwy, Elisabeth Heylen, Philippe Meersseman, Greet Hermans, Els Wauters, Alexander Wilmer, the CONTAGIOUS Consortium, Dominique Schols, Patrick Matthys, Ghislain Opdenakker, Rafael Elias Marques, Joost Wauters, Jennifer Vandooren, Paul Proost
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Review
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Abstract
KRAS mutations are the drivers of various cancers, including non–small cell lung cancer, colon cancer, and pancreatic cancer. Over the last 30 years, immense efforts have been made to inhibit KRAS mutants and oncogenic KRAS signaling using inhibitors. Recently, specific targeting of KRAS mutants with small molecules revived the hopes for successful therapies for lung, pancreatic, and colorectal cancer patients. Moreover, advances in gene editing, protein engineering, and drug delivery formulations have revolutionized cancer therapy regimens. New therapies aim to improve immune surveillance and enhance antitumor immunity by precisely targeting cancer cells harboring oncogenic KRAS. Here, we review recent KRAS-targeting strategies, their therapeutic potential, and remaining challenges to overcome. We also highlight the potential synergistic effects of various combinatorial therapies in preclinical and clinical trials.
Authors
Hande Asimgil, Utku Ertetik, Nedim Can Çevik, Menar Ekizce, Alper Doğruöz, Muazzez Gökalp, Elif Arık-Sever, Rouzanna Istvanffy, Helmut Friess, Güralp Onur Ceyhan, Ihsan Ekin Demir
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Abstract
Impaired glucose metabolism is observed in obesity and type 2 diabetes. Glucose controls gene expression through the transcription factor ChREBP in liver and adipose tissues. Mlxipl encodes two isoforms, ChREBPα, the full-length form which translocation into the nucleus is under the control of glucose and, ChREBPβ, a constitutively nuclear shorter form. ChREBPβ gene expression in white adipose tissue is strongly associated with insulin sensitivity. Here, we investigated the consequences of ChREBPβ deficiency on insulin action and energy balance. ChREBPβ-deficient male and female C57BL6/J and FVB/N mice were produced using CRISPR-Cas9-mediated gene editing. Unlike global ChREBP deficiency, lack of ChREBPβ showed modest effects on gene expression in adipose tissues and liver, with variations seen chiefly in brown adipose tissue. In mice fed chow and high fat diets, lack of ChREBPβ had moderate effects on body composition and insulin sensitivity. ChREBPβ deficiency did not prevent the whitening of brown adipose tissue reported in total ChREBP knock out mice at thermoneutrality. These findings reveal that ChREBPβ is dispensable for metabolic adaptations to nutritional and thermic challenges.
Authors
Emeline Recazens, Geneviève Tavernier, Jérémy Dufau, Camille Bergoglio, Fadila Benhamed, Stéphanie Cassant-Sourdy, Marie-Adeline Marques, Sylvie Caspar-Bauguil, Alice Brion, Laurent Monbrun, Renaud Dentin, Clara Ferrier, Mélanie Leroux, Pierre-Damien Denechaud, Cedric Moro, Jean-Paul Concordet, Catherine Postic, Etienne Mouisel, Dominique Langin
Abstract
Total body irradiation (TBI) targets sensitive bone marrow hematopoietic cells and gut epithelial cells causing their death and TBI induces the state of immunodeficiency combined with intestinal dysbiosis and non-productive immune responses. We found enhanced Pseudomonas aeruginosa (PA) colonization of the gut leading to the host cell death and strikingly decreased survival of irradiated mice. PA-driven pathogenic mechanism includes theft-ferroptosis is realized via: i) curbing host anti-ferroptotic system GSH/GPx4 and ii) employing bacterial 15-lipoxygenase (pLoxA) to generate pro-ferroptotic signal - 15-hyderoperoxy-arachidonyl-PE (15-HpETE-PE) - in the intestines of irradiated/infected mice. Global redox phospholipidomics of the ileum revealed that lyso-phospholipids and oxidized phospholipids (particularly PEox) represented the major factors which contributed to the TBI+PA induced pathogenic changes. A lipoxygenase inhibitor, baicalein, significantly attenuated animal lethality, PA colonization, as well as intestinal epithelial cell death and generation of ferroptotic PEox signals. Opportunistic PA mechanisms included stimulation of the anti-inflammatory lipoxin A4 (LXA4) production and suppression of the pro-inflammatory hepoxilin A3 (HxA3) and leukotriene B4 (LTB4). Unearthing complex PA pathogenic/virulence mechanisms including effects on the host anti-/pro-inflammatory responses, lipid metabolism and ferroptotic cell death points to new therapeutic and radiomitigative targets.
Authors
Haider H. Dar, Michael W. Epperly, Vladimir A. Tyurin, Andrew A. Amoscato, Tamil S. Anthonymuthu, Austin B. Souryavong, Alexander A. Kapralov, Galina V. Shurin, Svetlana N. Samovich, Claudette M. St. Croix, Simon C. Watkins, Sally E. Wenzel, Rama K. Mallampalli, Joel S. Greenberger, Hulya Bayir, Valerian E. Kagan, Yulia Y. Tyurina
Abstract
Defective primary cilia cause a range of diseases called ciliopathies, which include hearing loss (HL). Variants in human oxysterol binding protein like 2 (OSBPL2/ORP2) are responsible for autosomal dominant nonsyndromic HL (DFNA67). However, the pathogenesis of OSBPL2 deficiency has not been fully elucidated. In this study, we showed that the Osbpl2-knockout (KO) mice exhibited progressive HL and abnormal cochlea development with defective cilia. Further research revealed that OSBPL2 was located at the base of kinocilia in hair cells (HCs) and primary cilia in supporting cells (SCs), and functioned in the maintenance of ciliogenesis by regulating the homeostasis of PI(4,5)P2 on the cilia membrane. OSBPL2 deficiency led to a significant increase of PI(4,5)P2 on the cilia membrane, which could be partially rescued by the overexpression of INPP5E. In addition, the key molecules in Sonic Hedgehog (Shh) signaling pathway (SMO and GLI3) were detected to be down-regulated in Osbpl2-KO HEI-OC1 cells. Our findings revealed that OSBPL2 deficiency resulted in ciliary defects and abnormal Shh signaling transduction in auditory cells, which helped to elucidate the underlying mechanism of OSBPL2 deficiency in HL.
Authors
Hairong Shi, Hongshun Wang, Cheng Zhang, Yajie Lu, Jun Yao, Zhibin Chen, Guangqian Xing, Qinjun Wei, Xin Cao
Abstract
BACKGROUND. Vaccine-elicited adaptive immunity is a prerequisite for control of SARS-CoV-2 infection. Multiple sclerosis (MS) disease-modifying therapies (DMTs) differentially target humoral and cellular immunity. A comprehensive comparison of MS DMTs on SARS-CoV-2 vaccine-specific immunity is needed, including quantitative and functional B and T cell responses. METHODS. Spike-specific antibody and T cell responses were measured before and following SARS-CoV-2 vaccination in a cohort of 80 subjects, including healthy controls and MS patients in six DMT groups: untreated, glatiramer acetate (GA), dimethyl fumarate (DMF), natalizumab (NTZ), sphingosine-1-phosphate (S1P) receptor modulators, and anti-CD20 monoclonal antibodies. Anti-spike antibody responses were quantified by Luminex assay, high-resolution spike epitope reactivity was mapped by VirScan, and pseudovirus neutralization was assessed. Spike-specific CD4+ and CD8+ T cell responses were characterized by activation-induced marker (AIM) expression, cytokine production, and tetramer analysis. RESULTS. Anti-spike IgG levels were similar between healthy controls, untreated MS, GA, DMF, and NTZ patients, but were significantly reduced in anti-CD20 and S1P-treated patients. Anti-spike seropositivity in anti-CD20 patients was significantly correlated with CD19+ B cell levels and inversely correlated with cumulative treatment duration. Spike epitope reactivity and pseudovirus neutralization was reduced in anti-CD20 and S1P patients, directly correlating with reduced spike receptor binding domain (RBD) IgG levels. Spike-specific CD4+ and CD8+ T cell reactivity remained robust across all groups except in S1P-treated patients in whom post-vaccine CD4+ T cell responses were attenuated. CONCLUSIONS. These findings from a large MS cohort exposed to a wide spectrum of MS immunotherapies have important implications for treatment-specific COVID-19 clinical guidelines. FUNDING. This work was supported by grants from the NIH 1K08NS107619 (JJS), NMSS TA- 1903-33713 (JJS), K08NS096117 (MRW), Westridge Foundation (MRW), Chan Zuckerberg Biohub (JLD), R01AI159260 (JAH), R01NS092835 (SSZ), R01AI131624 (SSZ), R21NS108159 (SSZ), NMSS RG1701-26628 (SSZ), and the Maisin Foundation (SSZ).
Authors
Joseph J. Sabatino Jr, Kristen Mittl, William M. Rowles, Kira McPolin, Jayant V. Rajan, Matthew T. Laurie, Colin R. Zamecnik, Ravi Dandekar, Bonny D. Alvarenga, Rita P. Loudermilk, Chloe Gerungan, Collin M. Spencer, Sharon A. Sagan, Danillo G. Augusto, Jessa R. Alexander, Joseph L. DeRisi, Jill A. Hollenbach, Michael R. Wilson, Scott S. Zamvil, Riley Bove
Abstract
Aristolochic acid (AA) is the causative nephrotoxic alkaloid in aristolochic acid nephropathy, which results in a tubulointerstitial fibrosis. AA causes direct proximal tubule damage. There is also an influx of macrophages, although their role in the pathogenesis is poorly understood. Here we demonstrate that AA directly stimulates migration, inflammation, and reactive oxygen species (ROS) production in macrophages ex vivo. Cells lacking interferon regulatory factor 4 (IRF4), a known regulator of macrophage migration and phenotype, had a reduced migratory response, though effects on ROS production and inflammation were preserved or increased relative to wild-type cells. Macrophage-specific IRF4 knockout mice were protected from both acute and chronic kidney effects of AA administration based on functional and histological analysis. Renal macrophages from kidneys of AA-treated macrophage-specific IRF4 knockout mice demonstrated increased apoptosis and ROS production compared with wildtype controls, indicating that AA directly polarizes macrophages to a promigratory and proinflammatory phenotype. However, knockout mice had reduced renal macrophage abundance following AA administration. While macrophages lacking IRF4 can adopt a proinflammatory phenotype upon AA exposure, their inability to migrate to the kidney and increased rates of apoptosis upon infiltration provide protection from AA in vivo. These results provide evidence of direct AA effects on macrophages in AAN and add to the growing body of evidence that supports a key role of IRF4 in modulating macrophage function in kidney injury.
Authors
Kensuke Sasaki, Andrew S. Terker, Jiaqi Tang, Shirong Cao, Juan Pablo Arroyo, Aolei Niu, Suwan Wang, Xiaofeng Fan, Yahua Zhang, Stephanie R. Bennett, Ming-zhi Zhang, Raymond C. Harris
