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Abstract

Clostridioides difficile is a major cause of health care–associated diarrhea. Severity ranges from mild to life-threatening, but this variability remains poorly understood. Microbiologic diagnosis of C. difficile infection (CDI) is straightforward but offers little insight into the patient’s prognosis or into pathophysiologic determinants of clinical trajectory. The aim of this study was to discover host-derived, CDI-specific fecal biomarkers involved in disease severity. Subjects without and with CDI diarrhea were recruited. CDI severity was based on Infectious Diseases Society of America/Society for Healthcare Epidemiology of America criteria. We developed a liquid chromatography tandem mass spectrometry approach to identify host-derived protein biomarkers from stool and applied it to diagnostic samples for cohort-wise comparison (CDI-negative vs. nonsevere CDI vs. severe CDI). Selected biomarkers were orthogonally confirmed and subsequently verified in a CDI mouse model. We identified a protein signature from stool, consisting of alpha-2-macroglobulin (A2MG), matrix metalloproteinase-7 (MMP-7), and alpha-1-antitrypsin (A1AT), that not only discriminates CDI-positive samples from non-CDI ones but also is potentially associated with disease severity. In the mouse model, this signature with the murine homologs of the corresponding proteins was also identified. A2MG, MMP-7, and A1AT serve as biomarkers in patients with CDI and define novel components of the host response that may determine disease severity.

Authors

Makan Golizeh, Kaitlin Winter, Lucie Roussel, Marija Landekic, Mélanie Langelier, Vivian G. Loo, Momar Ndao, Donald C. Vinh

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Abstract

Chronic kidney disease (CKD) causes progressive skeletal myopathy involving atrophy, weakness, and fatigue. Mitochondria have been thought to contribute to skeletal myopathy; however, the molecular mechanisms underlying muscle metabolism changes in CKD are unknown. We employed a comprehensive mitochondrial phenotyping platform to elucidate the mechanisms of skeletal muscle mitochondrial impairment in mice with adenine-induced CKD. CKD mice displayed significant reductions in mitochondrial oxidative phosphorylation (OXPHOS), which was strongly correlated with glomerular filtration rate, suggesting a link between kidney function and muscle mitochondrial health. Biochemical assays uncovered that OXPHOS dysfunction was driven by reduced activity of matrix dehydrogenases. Untargeted metabolomics analyses in skeletal muscle revealed a distinct metabolite profile in CKD muscle including accumulation of uremic toxins that strongly associated with the degree of mitochondrial impairment. Additional muscle phenotyping found CKD mice experienced muscle atrophy and increased muscle protein degradation, but only male CKD mice had lower maximal contractile force. CKD mice had morphological changes indicative of destabilization in the neuromuscular junction. This study provides the first comprehensive evaluation of mitochondrial health in murine CKD muscle to our knowledge and uncovers several unknown uremic metabolites that strongly associate with the degree of mitochondrial impairment.

Authors

Trace Thome, Ravi A. Kumar, Sarah K. Burke, Ram B. Khattri, Zachary R. Salyers, Rachel C. Kelley, Madeline D. Coleman, Demetra D. Christou, Russell T. Hepple, Salvatore T. Scali, Leonardo F. Ferreira, Terence E. Ryan

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Abstract

Cardiopulmonary bypass (CPB) is required during most cardiac surgeries. CBP drives systemic inflammation and multiorgan dysfunction that is especially severe in neonatal patients. Limited understanding of molecular mechanisms underlying CPB-associated inflammation presents a significant barrier to improve clinical outcomes. To better understand these clinical issues, we performed mRNA sequencing on total circulating leukocytes from neonatal patients undergoing CPB. Our data identify myeloid cells, particularly monocytes, as the major cell type driving transcriptional responses to CPB. Furthermore, IL-8 and TNF-α were inflammatory cytokines robustly upregulated in leukocytes from both patients and piglets exposed to CPB. To delineate the molecular mechanism, we exposed THP-1 human monocytic cells to CPB-like conditions, including artificial surfaces, high shear stress, and cooling/rewarming. Shear stress was found to drive cytokine upregulation via calcium-dependent signaling pathways. We also observed that a subpopulation of THP-1 cells died via TNF-α–mediated necroptosis, which we hypothesize contributes to post-CPB inflammation. Our study identifies a shear stress–modulated molecular mechanism that drives systemic inflammation in pediatric CPB patients. These are also the first data to our knowledge to demonstrate that shear stress causes necroptosis. Finally, we observe that calcium and TNF-α signaling are potentially novel targets to ameliorate post-CPB inflammation.

Authors

Lan N. Tu, Lance Hsieh, Masaki Kajimoto, Kevin Charette, Nataliya Kibiryeva, Adriana Forero, Sarah Hampson, Jennifer A. Marshall, James O’Brien, Marta Scatena, Michael A. Portman, Ram Savan, Chris Benner, Alberto Aliseda, Muhammad Nuri, Douglas Bittel, Peter Pastuzsko, Vishal Nigam

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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

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Abstract

Existing animal models of cystic fibrosis (CF) have provided key insights into CF pathogenesis but have been limited by short lifespans, absence of key phenotypes, and/or high maintenance costs. Here, we report the CRISPR/Cas9-mediated generation of CF rabbits, a model with a relatively long lifespan and affordable maintenance and care costs. CF rabbits supplemented solely with oral osmotic laxative had a median survival of approximately 40 days and died of gastrointestinal disease, but therapeutic regimens directed toward restoring gastrointestinal transit extended median survival to approximately 80 days. Surrogate markers of exocrine pancreas disorders were found in CF rabbits with declining health. CFTR expression patterns in WT rabbit airways mimicked humans, with widespread distribution in nasal respiratory and olfactory epithelia, as well as proximal and distal lower airways. CF rabbits exhibited human CF–like abnormalities in the bioelectric properties of the nasal and tracheal epithelia. No spontaneous respiratory disease was detected in young CF rabbits. However, abnormal phenotypes were observed in surviving 1-year-old CF rabbits as compared with WT littermates, and these were especially evident in the nasal respiratory and olfactory epithelium. The CF rabbit model may serve as a useful tool for understanding gut and lung CF pathogenesis and for the practical development of CF therapeutics.

Authors

Jie Xu, Alessandra Livraghi-Butrico, Xia Hou, Carthic Rajagopalan, Jifeng Zhang, Jun Song, Hong Jiang, Hong-Guang Wei, Hui Wang, Mohamad Bouhamdan, Jinxue Ruan, Dongshan Yang, Yining Qiu, Youming Xie, Ronald Barrett, Sharon McClellan, Hongmei Mou, Qingtian Wu, Xuequn Chen, Troy D. Rogers, Kristen J. Wilkinson, Rodney C. Gilmore, Charles R. Esther Jr., Khalequz Zaman, Xiubin Liang, Michael Sobolic, Linda Hazlett, Kezhong Zhang, Raymond A. Frizzell, Martina Gentzsch, Wanda K. O’Neal, Barbara R. Grubb, Y. Eugene Chen, Richard C. Boucher, Fei Sun

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Abstract

Activation of farnesoid X receptor (FXR) by obeticholic acid (OCA) reduces hepatic inflammation and fibrosis in patients with primary biliary cholangitis (PBC), a life-threatening cholestatic liver failure. Inhibition of bromodomain-containing protein 4 (BRD4) also has antiinflammatory, antifibrotic effects in mice. We determined the role of BRD4 in FXR function in bile acid (BA) regulation and examined whether the known beneficial effects of OCA are enhanced by inhibiting BRD4 in cholestatic mice. Liver-specific downregulation of BRD4 disrupted BA homeostasis in mice, and FXR-mediated regulation of BA-related genes, including small heterodimer partner and cholesterol 7 alpha-hydroxylase, was BRD4 dependent. In cholestatic mice, JQ1 or OCA treatment ameliorated hepatotoxicity, inflammation, and fibrosis, but surprisingly, was antagonistic in combination. Mechanistically, OCA increased binding of FXR, and the corepressor silencing mediator of retinoid and thyroid hormone receptor (SMRT) decreased NF-κB binding at inflammatory genes and repressed the genes in a BRD4-dependent manner. In patients with PBC, hepatic expression of FXR and BRD4 was significantly reduced. In conclusion, BRD4 is a potentially novel cofactor of FXR for maintaining BA homeostasis and hepatoprotection. Although BRD4 promotes hepatic inflammation and fibrosis in cholestasis, paradoxically, BRD4 is required for the antiinflammatory, antifibrotic actions of OCA-activated FXR. Cotreatment with OCA and JQ1, individually beneficial, may be antagonistic in treatment of liver disease patients with inflammation and fibrosis complications.

Authors

Hyunkyung Jung, Jinjing Chen, Xiangming Hu, Hao Sun, Shwu-Yuan Wu, Cheng-Ming Chiang, Byron Kemper, Lin-Feng Chen, Jongsook Kim Kemper

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Abstract

Glioblastoma multiforme (GBM) is a fatal human cancer in part because GBM stem cells are resistant to therapy and recurrence is inevitable. Previously, we demonstrated Zika virus (ZIKV) targets GBM stem cells and prevents death of mice with gliomas. Here, we evaluated the immunological basis of ZIKV-mediated protection against GBM. Introduction of ZIKV into the brain tumor increased recruitment of CD8+ T and myeloid cells to the tumor microenvironment. CD8+ T cells were required for ZIKV-dependent tumor clearance because survival benefits were lost with CD8+ T cell depletion. Moreover, while anti–PD-1 antibody monotherapy moderately improved tumor survival, when coadministered with ZIKV, survival increased. ZIKV-mediated tumor clearance also resulted in durable protection against syngeneic tumor rechallenge, which also depended on CD8+ T cells. To address safety concerns, we generated an immune-sensitized ZIKV strain, which was effective alone or in combination with immunotherapy. Thus, oncolytic ZIKV treatment can be leveraged by immunotherapies, which may prompt combination treatment paradigms for adult patients with GBM.

Authors

Sharmila Nair, Luciano Mazzoccoli, Arijita Jash, Jennifer Govero, Sachendra S. Bais, Tong Hu, Camila R. Fontes-Garfias, Chao Shan, Hideho Okada, Sujan Shresta, Jeremy N. Rich, Pei-Yong Shi, Michael S. Diamond, Milan G. Chheda

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Abstract

Idiopathic pulmonary fibrosis (IPF) is a progressive, irreversible fibrotic disease of the distal lung alveoli that culminates in respiratory failure and reduced lifespan. Unlike normal lung repair in response to injury, IPF is associated with the accumulation and persistence of fibroblasts and myofibroblasts, as well as continued production of collagen and other extracellular matrix (ECM) components. Prior in vitro studies have led to the hypothesis that the development of resistance to Fas-induced apoptosis by lung fibroblasts and myofibroblasts contributes to their accumulation in the distal lung tissues of IPF patients. Here, we test this hypothesis in vivo in the resolving model of bleomycin-induced pulmonary fibrosis in mice. Using genetic loss-of-function approaches to inhibit Fas signaling in fibroblasts, potentially novel flow cytometry strategies to quantify lung fibroblast subsets, and transcriptional profiling of lung fibroblasts by bulk and single cell RNA sequencing, we show that Fas is necessary for lung fibroblast apoptosis during homeostatic resolution of bleomycin-induced pulmonary fibrosis in vivo. Furthermore, we show that loss of Fas signaling leads to the persistence and continued profibrotic functions of lung fibroblasts. Our studies provide insights into the mechanisms that contribute to fibroblast survival, persistence, and continued ECM deposition in the context of IPF and how failure to undergo Fas-induced apoptosis impairs fibrosis resolution.

Authors

Elizabeth F. Redente, Sangeeta Chakraborty, Satria Sajuthi, Bart P. Black, Ben L. Edelman, Max A. Seibold, David W.H. Riches

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Abstract

Kir5.1 is an inwardly rectifying potassium (Kir) channel subunit abundantly expressed in the kidney and brain. We previously established the physiologic consequences of a Kcnj16 (gene encoding Kir5.1) knockout in the Dahl salt-sensitive rat (SSKcnj16–/–), which caused electrolyte/pH dysregulation and high-salt diet–induced mortality. Since Kir channel gene mutations may alter neuronal excitability and are linked to human seizure disorders, we hypothesized that SSKcnj16–/– rats would exhibit neurological phenotypes, including increased susceptibility to seizures. SSKcnj16–/– rats exhibited increased light sensitivity (fMRI) and reproducible sound-induced tonic-clonic audiogenic seizures confirmed by electroencephalography. Repeated seizure induction altered behavior, exacerbated hypokalemia, and led to approximately 38% mortality in male SSKcnj16–/– rats. Dietary potassium supplementation did not prevent audiogenic seizures but mitigated hypokalemia and prevented mortality induced by repeated seizures. These results reveal a distinct, nonredundant role for Kir5.1 channels in the brain, introduce a rat model of audiogenic seizures, and suggest that yet-to-be identified mutations in Kcnj16 may cause or contribute to seizure disorders.

Authors

Anna D. Manis, Oleg Palygin, Elena Isaeva, Vladislav Levchenko, Peter S. LaViolette, Tengis S. Pavlov, Matthew R. Hodges, Alexander Staruschenko

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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

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Abstract

Esophageal adenocarcinoma (EAC) develops from Barrett’s esophagus (BE), a chronic inflammatory state that can progress through a series of transformative dysplastic states before tumor development. While molecular and genetic changes of EAC tumors have been studied, immune microenvironment changes during Barrett’s progression to EAC remain poorly understood. In this study, we identify potential immunologic changes that can occur during BE-to-EAC progression. RNA sequencing (RNA-Seq) analysis on tissue samples from EAC patients undergoing surgical resection demonstrated that a subset of chemokines and cytokines, most notably IL6 and CXCL8, increased during BE progression to EAC. xCell deconvolution analysis investigating immune cell population changes demonstrated that the largest changes in expression during BE progression occurred in M2 macrophages, pro–B cells, and eosinophils. Multiplex immunohistochemical staining of tissue microarrays showed increased immune cell populations during Barrett’s progression to high-grade dysplasia. In contrast, EAC tumor sections were relatively immune poor, with a rise in PD-L1 expression and loss of CD8+ T cells. These data demonstrate that the EAC microenvironment is characterized by poor cytotoxic effector cell infiltration and increased immune inhibitory signaling. These findings suggest an immunosuppressive microenvironment, highlighting the need for further studies to explore immune modulatory therapy in EAC.

Authors

Kiran H. Lagisetty, Dyke P. McEwen, Derek J. Nancarrow, Johnathon G. Schiebel, Daysha Ferrer-Torres, Dipankar Ray, Timothy L. Frankel, Jules Lin, Andrew C. Chang, Laura A. Kresty, David G. Beer

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Abstract

The CNS is regarded as an immunoprivileged organ, evading routine immune surveillance; however, the coordinated development of immune responses profoundly influences outcomes after brain injury. Innate lymphoid cells (ILCs) are cytokine-producing cells that are critical for the initiation, modulation, and resolution of inflammation, but the functional relevance and mechanistic regulation of ILCs are unexplored after acute brain injury. We demonstrate increased proliferation of all ILC subtypes within the meninges for up to 1 year after experimental traumatic brain injury (TBI) while ILCs were present within resected dura and elevated within cerebrospinal fluid (CSF) of moderate-to-severe TBI patients. In line with energetic derangements after TBI, inhibition of the metabolic regulator, AMPK, increased meningeal ILC expansion, whereas AMPK activation suppressed proinflammatory ILC1/ILC3 and increased the frequency of IL-10–expressing ILC2 after TBI. Moreover, intracisternal administration of IL-33 activated AMPK, expanded ILC2, and suppressed ILC1 and ILC3 within the meninges of WT and Rag1–/– mice, but not Rag1–/– IL2rg–/– mice. Taken together, we identify AMPK as a brake on the expansion of proinflammatory, CNS-resident ILCs after brain injury. These findings establish a mechanistic framework whereby immunometabolic modulation of ILCs may direct the specificity, timing, and magnitude of cerebral immunity.

Authors

Babak Baban, Molly Braun, Hesam Khodadadi, Ayobami Ward, Katelyn Alverson, Aneeq Malik, Khoi Nguyen, Skon Nazarian, David C. Hess, Scott Forseen, Alexander F. Post, Fernando L. Vale, John R. Vender, Md. Nasrul Hoda, Omid Akbari, Kumar Vaibhav, Krishnan M. Dhandapani

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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

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Abstract

The rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), coupled with a lack of therapeutics, has paralyzed the globe. Although significant effort has been invested in identifying antibodies that block infection, the ability of antibodies to target infected cells through Fc interactions may be vital to eliminate the virus. To explore the role of Fc activity in SARS-CoV-2 immunity, the functional potential of a cross–SARS-reactive antibody, CR3022, was assessed. CR3022 was able to broadly drive antibody effector functions, providing critical immune clearance at entry and upon egress. Using selectively engineered Fc variants, no protection was observed after administration of WT IgG1 in mice or hamsters. Conversely, the functionally enhanced Fc variant resulted in increased pathology in both the mouse and hamster models, causing weight loss in mice and enhanced viral replication and weight loss in the more susceptible hamster model, highlighting the pathological functions of Fc-enhancing mutations. These data point to the critical need for strategic Fc engineering for the treatment of SARS-CoV-2 infection.

Authors

Caroline Atyeo, Matthew D. Slein, Stephanie Fischinger, John Burke, Alexandra Schäfer, Sarah R. Leist, Natalia A. Kuzmina, Chad Mire, Anna Honko, Rebecca Johnson, Nadia Storm, Matthew Bernett, Pei Tong, Teng Zuo, Junrui Lin, Adam Zuiani, Caitlyn Linde, Todd Suscovich, Duane R. Wesemann, Anthony Griffiths, John R. Desjarlais, Boris D. Juelg, Jaap Goudsmit, Alexander Bukreyev, Ralph Baric, Galit Alter

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Abstract

RNA-binding proteins (RBPs) are essential factors required for the physiological function of neurons, muscle, and other tissue types. In keeping with this, a growing body of genetic, clinical, and pathological evidence indicates that RBP dysfunction and/or gene mutation leads to neurodegeneration and myopathy. Here, we summarize the current understanding of matrin 3 (MATR3), a poorly understood RBP implicated not only in ALS and frontotemporal dementia but also in distal myopathy. We begin by reviewing MATR3’s functions, its regulation, and how it may be involved in both sporadic and familial neuromuscular disease. We also discuss insights gleaned from cellular and animal models of MATR3 pathogenesis, the links between MATR3 and other disease-associated RBPs, and the mechanisms underlying RBP-mediated disorders.

Authors

Ahmed M. Malik, Sami J. Barmada

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Abstract

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) with CCR5– donor cells is the only treatment known to cure HIV-1 in patients with underlying malignancy. This is likely due to a donor cell–mediated graft-versus-host effect targeting HIV reservoirs. Allo-HSCT would not be an acceptable therapy for most people living with HIV due to the transplant-related side effects. Chimeric antigen receptor (CAR) immunotherapies specifically traffic to malignant lymphoid tissues (lymphomas) and, in some settings, are able to replace allo-HSCT. Here, we quantified the engraftment of HSC-derived, virus-directed CAR T cells within HIV reservoirs in a macaque model of HIV infection, using potentially novel IHC assays. HSC-derived CAR cells trafficked to and displayed multilineage engraftment within tissue-associated viral reservoirs, persisting for nearly 2 years in lymphoid germinal centers, the brain, and the gastrointestinal tract. Our findings demonstrate that HSC-derived CAR+ cells reside long-term and proliferate in numerous tissues relevant for HIV infection and cancer.

Authors

Isaac M. Barber-Axthelm, Valerie Barber-Axthelm, Kai Yin Sze, Anjie Zhen, Gajendra W. Suryawanshi, Irvin S.Y. Chen, Jerome A. Zack, Scott G. Kitchen, Hans-Peter Kiem, Christopher W. Peterson

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Abstract

BACKGROUND Although CDK4/6 inhibitors are an established treatment for hormone receptor–positive, HER2-negative metastatic breast cancers, their benefit in other malignancies remains limited.METHODS We investigated factors associated with clinical outcomes from CDK4/6 inhibitor–based therapy among patients with G1/S phase cell-cycle alterations (CDK4/6 amplifications, CCND1/2/3 amplifications, or CDKN2A/B alterations).RESULTS Overall, 2457 patients with diverse solid tumors that underwent clinical-grade, next-generation sequencing (182–465 genes) and therapy outcome of (non–breast cancer) patients treated with matched CDK4/6 inhibitors were analyzed. G1/S phase cell-cycle alterations occurred in 20.6% (507 of 2457) of patients; 99% of those patients (n = 501) harbored ≥1 characterized co-alteration (median, 4; range, 0–24). In 40 patients with G1/S phase cell-cycle alterations given CDK4/6 inhibitors as part of their regimen, significantly longer median progression-free survival (PFS) was observed when CDK4/6 inhibitor–based therapies matched a larger proportion of tumor alterations, often because CDK4/6 inhibitors were administered together with other drugs that were matched to genomic co-alterations, hence achieving a high matching score (high vs. low [≥50% vs. <50%] matching score, PFS, 6.2 vs. 2.0 months, P < 0.001 [n = 40] [multivariate]) and higher rate of stable disease ≥6 months or an objective response (57% vs. 21%, P = 0.048).CONCLUSION In summary, in cell-cycle–altered cancers, matched CDK4/6 inhibitors, as part of an individualized regimen targeting a majority of genomic alterations, was independently associated with longer PFS.TRIAL REGISTRATION ClinicalTrials.gov NCT02478931.FUNDING Joan and Irwin Jacobs Fund, National Cancer Institute (P30 CA023100, R01 CA226803), and the FDA (R01 FD006334).

Authors

Shumei Kato, Ryosuke Okamura, Jacob J. Adashek, Noor Khalid, Suzanna Lee, Van Nguyen, Jason K. Sicklick, Razelle Kurzrock

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Abstract

Alveolar macrophages (AMs) are differentially regulated by human surfactant protein-A1 (SP-A1) or SP-A2. However, AMs are very heterogeneous and differences are difficult to characterize in intact cells. Using the Toponome Imaging System (TIS), an imaging technique that uses sequential immunostaining to identify patterns of biomarker expression or combinatorial molecular phenotypes (CMPs), we studied individual single cells and identified subgroups of AMs (n = 168) from SP-A–KO mice and mice expressing either SP-A1 or SP-A2. The effects, as shown by CMPs, of SP-A1 and SP-A2 on AMs were significant and differed. SP-A1 AMs were the most diverse and shared the fewest CMPs with KO and SP-A2. Clustering analysis of each group showed 3 clusters where the CMP-based phenotype was distinct in each cluster. Moreover, a clustering analysis of all 168 AMs revealed 10 clusters, many dominated by 1 group. Some CMP overlap among groups was observed with SP-A2 AMs sharing the most CMPs and SP-A1 AMs the fewest. The CMP-based patterns identified here provide a basis for understanding not only AMs’ diversity, but also most importantly, the molecular basis for the diversity of functional differences in mouse models where the impact of genetics of innate immune molecules on AMs has been studied.

Authors

David S. Phelps, Vernon M. Chinchilli, Judith Weisz, Lili Yang, Debra Shearer, Xuesheng Zhang, Joanna Floros

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Abstract

Enhanced energy expenditure in brown (BAT) and white adipose tissues (WAT) can be therapeutic against metabolic diseases. We examined the thermogenic role of adipose α/β-hydrolase domain 6 (ABHD6), which hydrolyzes monoacylglycerol (MAG), by employing adipose-specific ABHD6-KO mice. Control and KO mice showed similar phenotypes at room temperature and thermoneutral conditions. However, KO mice were resistant to hypothermia, which can be accounted for by the simultaneously increased lipolysis and lipogenesis of the thermogenic glycerolipid/free fatty acid (GL/FFA) cycle in visceral fat, despite unaltered uncoupling protein 1 expression. Upon cold stress, nuclear 2-MAG levels increased in visceral WAT of the KO mice. Evidence is provided that 2-MAG causes activation of PPARα in white adipocytes, leading to elevated expression and activity of GL/FFA cycle enzymes. In the ABHD6-ablated BAT, glucose and oxidative metabolism were elevated upon cold induction, without changes in GL/FFA cycle and lipid turnover. Moreover, response to in vivo β3-adrenergic stimulation was comparable between KO and control mice. Our data reveal a MAG/PPARα/GL/FFA cycling metabolic signaling network in visceral adipose tissue, which contributes to cold tolerance, and that adipose ABHD6 is a negative modulator of adaptive thermogenesis.

Authors

Pegah Poursharifi, Camille Attané, Yves Mugabo, Anfal Al-Mass, Anindya Ghosh, Clémence Schmitt, Shangang Zhao, Julian Guida, Roxane Lussier, Heidi Erb, Isabelle Chenier, Marie-Line Peyot, Erik Joly, Christophe Noll, André C. Carpentier, S.R. Murthy Madiraju, Marc Prentki

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Abstract

Nonalcoholic fatty liver disease (NAFLD) is characterized by hepatic lipid accumulation. The transmembrane 6 superfamily member 2 (TM6SF2) E167K genetic variant associates with NAFLD and with reduced plasma triglyceride levels in humans. However, the molecular mechanisms underlying these associations remain unclear. We hypothesized that TM6SF2 E167K affects hepatic very low-density lipoprotein (VLDL) secretion and studied the kinetics of apolipoprotein B100 (apoB100) and triglyceride metabolism in VLDL in homozygous subjects. In 10 homozygote TM6SF2 E167K carriers and 10 matched controls, we employed stable-isotope tracer and compartmental modeling techniques to determine apoB100 and triglyceride kinetics in the 2 major VLDL subfractions: large triglyceride-rich VLDL1 and smaller, less triglyceride-rich VLDL2. VLDL1-apoB100 production was markedly reduced in homozygote TM6SF2 E167K carriers compared with controls. Likewise, VLDL1-triglyceride production was 35% lower in the TM6SF2 E167K carriers. In contrast, the direct production rates for VLDL2-apoB100 and triglyceride were not different between carriers and controls. In conclusion, the TM6SF2 E167K genetic variant was linked to a specific reduction in hepatic secretion of large triglyceride-rich VLDL1. The impaired secretion of VLDL1 explains the reduced plasma triglyceride concentration and provides a basis for understanding the lower risk of cardiovascular disease associated with the TM6SF2 E167K genetic variant.

Authors

Jan Borén, Martin Adiels, Elias Björnson, Niina Matikainen, Sanni Söderlund, Joel Rämö, Marcus Ståhlman, Pietari Ripatti, Samuli Ripatti, Aarno Palotie, Rosellina M. Mancina, Antti Hakkarainen, Stefano Romeo, Chris J. Packard, Marja-Riitta Taskinen

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Abstract

Convalescent plasma with severe acute respiratory disease coronavirus 2 (SARS-CoV-2) antibodies (CCP) may hold promise as treatment for Coronavirus Disease 2019 (COVID-19). We compared the mortality and clinical outcome of patients with COVID-19 who received 200mL of CCP with a Spike protein IgG titer ≥1:2,430 (median 1:47,385) within 72 hours of admission to propensity score-matched controls cared for at a medical center in the Bronx, between April 13 to May 4, 2020. Matching criteria for controls were age, sex, body mass index, race, ethnicity, comorbidities, week of admission, oxygen requirement, D-dimer, lymphocyte counts, corticosteroids, and anticoagulation use. There was no difference in mortality or oxygenation between CCP recipients and controls at day 28. When stratified by age, compared to matched controls, CCP recipients <65 years had 4-fold lower mortality and 4-fold lower deterioration in oxygenation or mortality at day 28. For CCP recipients, pre-transfusion Spike protein IgG, IgM and IgA titers were associated with mortality at day 28 in univariate analyses. No adverse effects of CCP were observed. Our results suggest CCP may be beneficial for hospitalized patients <65 years, but data from controlled trials is needed to validate this finding and establish the effect of ageing on CCP efficacy.

Authors

Hyun ah Yoon, Rachel Bartash, Inessa Gendlina, Johanna Rivera, Antonio Nakouzi, Robert H. Bortz III, Ariel S. Wirchnianski, Monika Paroder, Karen Fehn, Leana Serrano-Rahman, Rachelle Babb, Uzma N. Sarwar, Denise Haslwanter, Ethan Laudermilch, Catalina Florez, M. Eugenia Dieterle, Rohit K. Jangra, J. Maximilian Fels, Karen Tong, Margarette C. Mariano, Olivia Vergnolle, George I. Georgiev, Natalia G. Herrera, Ryan J. Malonis, Jose A. Quiroz, Nicholas C. Morano, Gregory J. Krause, Joseph M. Sweeney, Kelsie Cowman, Stephanie A. Allen, Jayabhargav Annam, Ariella Applebaum, Daniel Barboto, Ahmed Khokhar, Brianna J. Lally, Audrey Lee, Max Lee, Avinash Malaviya, Reise Sample, Xiuyi A. Yang, Yang Li, Rafael E. Ruiz, Raja Thota, Jason Barnhill, Doctor Y. Goldstein, Joan Uehlinger, Scott J. Garforth, Steven C. Almo, Jonathan R. Lai, Morayma Reyes Gil, Amy S. Fox, Kartik Chandran, Tao Wang, Johanna P. Daily, Liise-anne Pirofski

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Abstract

The metabotropic glutamate receptor 7 (mGlu7) is a G protein-coupled receptor that has been recently linked to neurodevelopmental disorders. This association is supported by the identification of GRM7 variants in patients with autism spectrum disorder, attention deficit hyperactivity disorder, and severe developmental delay. One GRM7 mutation previously reported in two patients results in a single amino acid change, I154T, within the mGlu7 ligand-binding domain. Here, we report two new patients with this mutation who present with severe developmental delay and epilepsy. Functional studies of the mGlu7-I154T mutant reveal that this substitution results in significant loss of mGlu7 protein expression in HEK293A cells and in mice. We show that this occurs post-transcriptionally at the level of protein expression and trafficking. Similar to mGlu7 global knockout mice, mGlu7-I154T animals exhibit reduced motor coordination, deficits in contextual fear learning, and seizures. This provides the first functional evidence that a disease-associated mutation affecting the mGlu7 receptor is sufficient to cause neurological dysfunction in mice and further validates GRM7 as a disease-causing gene in the human population.

Authors

Nicole M. Fisher, Aqeela AlHashim, Aditi B. Buch, Hana Badivuku, Manar M. Samman, Kelly M. Weiss, Gabriela I. Cestero, Mark D. Does, Jerri M. Rook, Craig W. Lindsley, P. Jeffrey Conn, Rocco G. Gogliotti, Colleen M. Niswender

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Abstract

The pandemic of Coronavirus Disease 19 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become one of the worst public health crises. However, knowledge about the dynamics of antibody responses in COVID-19 patients is still poorly understood. In this study, we performed serological study with serum specimens collected at the acute and the convalescent phases from 104 severe COVID-19 patients who were the first wave of COVID-19 cases in Wuhan, China. Our findings uncovered that neutralizing antibodies to SARS-CoV-2 are persistent at least for more than 6 months in severe COVID-19 patients, despite that immunoglobulin G (IgG) levels against receptor binding domain (RBD) and nucleocapsid protein (N) IgG declined from the acute to the convalescent phase. Moreover, we demonstrate that the level of RBD-IgG is capable of correlating with SARS-CoV-2-neutralizing activities in COVID-19 serum. In summary, our findings identify the magnitude, functionality and longevity of antibody responses in COVID-19 patients, which sheds light on better understanding of humoral immune response to COVID-19, and would be beneficial for developing vaccines.

Authors

Yang Han, Peipei Liu, Yang Qiu, Jie Zhou, Ying Liu, Xujuan Hu, Qingyu Yang, Rui Huang, Xinyue Wen, Hao Song, Pengcheng Yu, Mengjie Yang, Jing Zhang, William J. Liu, Ke Peng, Guizhen Wu, Dingyu Zhang, Xi Zhou, Ying Wu

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Abstract

This Perspective discusses disparities in COVID-19 infection and outcome in ethnically diverse groups and considerations that should be taken to rectify this disparity going forward.

Authors

John M. Carethers

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Abstract

TAK-243 is a first-in-class inhibitor of ubiquitin-like modifier activating enzyme 1 (UBA1) that catalyzes ubiquitin activation, the first step in the ubiquitylation cascade. Based on its preclinical efficacy and tolerability, TAK-243 has been advanced to phase 1 clinical trials in advanced malignancies. Nonetheless, the determinants of TAK-243 sensitivity remain largely unknown. Here, we conducted a genome-wide CRISPR/Cas9 knockout screen in acute myeloid leukemia (AML) cells in the presence of TAK-243 to identify genes essential for TAK-243 action. We identified BEN domain-containing protein 3 (BEND3), a transcriptional repressor and a regulator of chromatin organization, as the top gene whose knockout confers resistance to TAK-243 in vitro and in vivo. Knockout of BEND3 dampened TAK-243 effects on ubiquitylation, proteotoxic stress, and DNA damage response. BEND3 knockout upregulated the ABC efflux transporter breast cancer resistance protein (BCRP; ABCG2), and reduced the intracellular levels of TAK-243. TAK-243 sensitivity correlated with BCRP expression in cancer cell lines of different origin. Moreover, chemical inhibition and genetic knockdown of BCRP sensitized intrinsically resistant high-BCRP cells to TAK-243. Thus, our data demonstrate that BEND3 regulates the expression of BCRP for which TAK-243 is a substrate. Moreover, BCRP expression could serve as a predictor of TAK-243 sensitivity.

Authors

Samir H. Barghout, Ahmed Aman, Kazem Nouri, Zachary Blatman, Karen Arevalo, Geethu E. Thomas, Neil MacLean, Rose Hurren, Troy Ketela, Mehakpreet Saini, Moustafa Abohawya, Taira Kiyota, Rima Al-Awar, Aaron D. Schimmer

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Latest issue: January 11, 2021

January 11, 2021, issue

On the cover:
Stem cell-derived CAR-T cells traffic to HIV reservoirs in macaques

Barber-Axthelm et al. show that hematopoietic stem cell-derived, chimeric antigen receptor (CAR) T cells can traffic to sites of HIV latency in a nonhuman primate model of HIV. The cover image is a fluorescent multiplex IHC (mIHC) image of a pigtail macaque axillary lymph node, stained with antibodies specific for CD4CAR (green), CD20 (cyan), CD3 (yellow), CD68 and CD163 (gray), CD8 (red), and CD35 (magenta). DAPI nuclear counterstain is in blue.

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January 2021 JCI This Month

JCI This Month is a digest of the research, reviews, and other features published each month.

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