On the cover:
Stem cells in postviral lung disease
Wu et al. identify a distinct pathway for progressive and long-term lung disease that develops after respiratory viral infection. The cover image shows new basal epithelial cells during postviral lung disease, with immunostaining for IL-33 (red) and Krt5 (green), and nuclear counterstain (blue).
Circadian disruption is pervasive and can occur at multiple organizational levels, contributing to poor health outcomes at individual and population levels. Evidence points to a bidirectional relationship, in that circadian disruption increases disease severity and many diseases can disrupt circadian rhythms. Importantly, circadian disruption can increase the risk for the expression and development of neurologic, psychiatric, cardiometabolic, and immune disorders. Thus, harnessing the rich findings from preclinical and translational research in circadian biology to enhance health via circadian-based approaches represents a unique opportunity for personalized/precision medicine and overall societal well-being. In this Review, we discuss the implications of circadian disruption for human health using a bench-to-bedside approach. Evidence from preclinical and translational science is applied to a clinical and population-based approach. Given the broad implications of circadian regulation for human health, this Review focuses its discussion on selected examples in neurologic, psychiatric, metabolic, cardiovascular, allergic, and immunologic disorders that highlight the interrelatedness between circadian disruption and human disease and the potential of circadian-based interventions, such as bright light therapy and exogenous melatonin, as well as chronotherapy to improve and/or modify disease outcomes.
Anna B. Fishbein, Kristen L. Knutson, Phyllis C. Zee
Neurodegenerative diseases encompass a large group of conditions that are clinically and pathologically diverse yet are linked by a shared pathology of misfolded proteins. The accumulation of insoluble aggregates is accompanied by a progressive loss of vulnerable neurons. For some patients, the symptoms are motor focused (ataxias), while others experience cognitive and psychiatric symptoms (dementias). Among the shared symptoms of neurodegenerative diseases is a disruption of the sleep/wake cycle that occurs early in the trajectory of the disease and may be a risk factor for disease development. In many cases, the disruption in the timing of sleep and other rhythmic physiological markers immediately raises the possibility of neurodegeneration-driven disruption of the circadian timing system. The aim of this Review is to summarize the evidence supporting the hypothesis that circadian disruption is a core symptom within neurodegenerative diseases, including Alzheimer’s disease, Huntington’s disease, and Parkinson’s disease, and to discuss the latest progress in this field. The Review discusses evidence that neurodegenerative processes may disrupt the structure and function of the circadian system and describes circadian-based interventions as well as timed drug treatments that may improve a wide range of symptoms associated with neurodegenerative disorders. It also identifies key gaps in our knowledge.
Loss of atrioventricular conduction system (AVCS) cells due to either inherited or acquired deficits leads to conduction diseases, which can deteriorate into fatal cardiac arrhythmias and sudden death. In this issue of the JCI, Wang et al. constructed a mouse model of atrioventricular block (AVB) by inducing AVCS cell–specific injury using the Cx30.2 enhancer to drive expression of diphtheria toxin fragment A. AVCS cell ablation in adult mice led to irreversible AVB. jkjkIn contrast, AVCS cell injury in neonatal mice was followed by spontaneous recovery in a subset of mice, revealing a limited postnatal time window during which the regeneration of AVCS cells can occur as a result of cellular plasticity. This exciting study paves the way for future research into biological or cellular treatment approaches for cardiac conduction diseases by exploiting the regenerative potential of AVCS cells.
Satadru K. Lahiri, Mohit M. Hulsurkar, Xander H.T. Wehrens
Innovative approaches in the field of cytokine engineering are revolutionizing the cancer therapeutic landscape. The IL-15 cytokine is particularly enticing as a cancer immunotherapy due to its natural propensity for stimulating the proliferation and activation of NK and CD8+ T cells. In a recent IL-15 engineering approach, the cytokine was conjugated to polyethylene glycol, and the resulting molecule (NKTR-255) exhibited potent antitumor activities. In this issue of the JCI, Robinson et al. mechanistically explored NKTR-255 and compared its immune profile to that of the unconjugated IL-15 cytokine. The authors found that NKTR-255 employs distinct activities on NK compared with CD8+ T cells. NKTR-255 signaling also showed less dependence on the expression of the IL-15 receptor-α (IL-15Rα) chain compared with unconjugated IL-15. Collectively, these findings will advance IL-15–based clinical therapies and, more generally, benefit the field of cancer immunotherapy.
IL-33 is a well-studied cytokine that resides normally within nuclei but can be released by cell damage or stress to then signal via a single receptor widely expressed on immune cells to promote host resistance and type 2 allergic immunity. In this issue of the JCI, Wu et al. used a well-established model of mouse Sendai viral infection to show that IL-33 was induced in distal lung airway epithelium, specifically in cell-cycling basal cells. IL-33 induced cell-cycling basal cells to expand and migrate into the alveolar compartment, presumably to restore barrier function. However, restoring barrier function with airway-derived cells may also result in persistent alveolar metaplasia. Surprisingly, nuclear IL-33 in this system acted cell autonomously, independently of release and conventional ST2 (IL1RL1) receptor signaling. The findings uncover a signaling role for nuclear IL-33 in viral activation of mouse basal cells and add to the well-known “alarmin” function of IL-33.
Over the past decade, chimeric antigen receptor (CAR) T cells have emerged as the prototype gene therapy for B cell leukemias. These so-called living drugs are derived from a patient’s own cells, reprogrammed to recognize and destroy cancer cells, and then reintroduced into the body. The huge success of this therapy for cancer is rooted in pioneering clinical and preclinical studies, established more than three decades ago, focused on persistent HIV-1 infection. In this issue of the JCI, Bingfeng Liu et al. revisit HIV-specific CAR T cells in an important clinical study that supports broader application of this groundbreaking therapy. Although curative endpoints were not achieved, these findings lay the foundation for augmented approaches applying combinatorial technologies including antigen supplementation.
Enhanced signaling via RTKs in pulmonary hypertension (PH) impedes current treatment options because it perpetuates proliferation and apoptosis resistance of pulmonary arterial smooth muscle cells (PASMCs). Here, we demonstrated hyperphosphorylation of multiple RTKs in diseased human vessels and increased activation of their common downstream effector phosphatidylinositol 3′-kinase (PI3K), which thus emerged as an attractive therapeutic target. Systematic characterization of class IA catalytic PI3K isoforms identified p110α as the key regulator of pathogenic signaling pathways and PASMC responses (proliferation, migration, survival) downstream of multiple RTKs. Smooth muscle cell–specific genetic ablation or pharmacological inhibition of p110α prevented onset and progression of pulmonary hypertension (PH) as well as right heart hypertrophy in vivo and even reversed established vascular remodeling and PH in various animal models. These effects were attributable to both inhibition of vascular proliferation and induction of apoptosis. Since this pathway is abundantly activated in human disease, p110α represents a central target in PH.
Eva M. Berghausen, Wiebke Janssen, Marius Vantler, Leoni L. Gnatzy-Feik, Max Krause, Arnica Behringer, Christine Joseph, Mario Zierden, Henrik ten Freyhaus, Anna Klinke, Stephan Baldus, Miguel A. Alcazar, Rajkumar Savai, Soni Savai Pullamsetti, Dickson W.L. Wong, Peter Boor, Jean J. Zhao, Ralph T. Schermuly, Stephan Rosenkranz
The cardiac conduction system (CCS) ensures regular contractile function, and injury to any of its components can cause cardiac dysrhythmia. Although all cardiomyocytes (CMs) originate from common progenitors, the CCS is composed of biologically distinct cell types with unique functional and developmental characteristics. In contrast to ventricular cardiomyocytes, which continue to proliferate after birth, most CCS cells terminally exit the cell cycle during fetal development. Although the CCS should thus provide a poor substrate for postnatal injury repair, its regenerative capacity remains untested. Here, we describe a genetic system for ablating CMs that reside within the atrioventricular conduction system (AVCS). Adult mouse AVCS ablation resulted in regenerative failure characterized by persistent atrioventricular conduction defects and contractile dysfunction. In contrast, AVCS injury in neonatal mice led to recovery in a subset of these mice, thus providing evidence for CCS plasticity. Furthermore, CM proliferation did not appear to completely account for the observed functional recovery, suggesting that mechanisms regulating recovery from dysrhythmia are likely to be distinct from cardiac regeneration associated with ventricular injury. Taken together, we anticipate that our results will motivate further mechanistic studies of CCS plasticity and enable the exploration of rhythm restoration as an alternative therapeutic strategy.
Lin Wang, Minoti Bhakta, Antonio Fernandez-Perez, Nikhil V. Munshi
We previously demonstrated that tumor-infiltrating lymphocytes (TIL) in human breast cancer sometimes form organized tertiary lymphoid structures (TLS) characterized by CXCL13-producing T follicular helper (Tfh) cells. The present study found that CD4+ Tfh TIL, CD8+ TIL, and TIL-B, colocalizing in TLS, all express the CXCL13 receptor CXCR5. An ex vivo functional assay determined that only activated, functional Th1-oriented Tfh TIL (PD-1hiICOSint phenotype) provide help for immunoglobulin and IFN-γ production. A functional Tfh TIL presence signals an active TLS, characterized by humoral (immunoglobulins, Ki-67+ TIL-B in active germinal centers) and cytotoxic (GZMB+CD8+ and GZMB+CD68+ TIL plus Th1 gene expression) immune responses. Analysis of active versus inactive TLS in untreated patients revealed that the former are associated with positive clinical outcomes. TLS also contain functional T follicular regulatory (Tfr) TIL, which are characterized by a CD25+CXCR5+GARP+FOXP3+ phenotype and a demethylated FOXP3 gene. Functional Tfr inhibited functional Tfh activities via a glycoprotein A repetitions predominant (GARP)-associated TGF-β–dependent mechanism. The activity of tumor-associated TLS was dictated by the relative balance between functional Tfh TIL and functional Tfr TIL. These data provide mechanistic insight into TLS processes orchestrated by functional Th1-oriented Tfh TIL, including TIL-B and CD8+ TIL activation and immunological memory generation. Tfh TIL, regulated by functional Tfr TIL, are an expected key target of PD-1/PD-L1 blockade.
Grégory Noël, Mireille Langouo Fontsa, Soizic Garaud, Pushpamali De Silva, Alexandre de Wind, Gert G. Van den Eynden, Roberto Salgado, Anaïs Boisson, Hanne Locy, Noémie Thomas, Cinzia Solinas, Edoardo Migliori, Céline Naveaux, Hugues Duvillier, Sophie Lucas, Ligia Craciun, Kris Thielemans, Denis Larsimont, Karen Willard-Gallo
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Insulin and IGF-1 are essential for adipocyte differentiation and function. Mice lacking insulin and IGF-1 receptors in fat (FIGIR-KO, fat-specific IGF-1 receptor and insulin receptor–KO) exhibit complete loss of white and brown adipose tissue (WAT and BAT), glucose intolerance, insulin resistance, hepatosteatosis, and cold intolerance. To determine the role of FOXO transcription factors in the altered adipose phenotype, we generated FIGIR-KO mice with fat-specific KO of fat-expressed Foxos [Foxo1, Foxo3, Foxo4] (F-Quint–KO). Unlike FIGIR-KO mice, F-Quint–KO mice had normal BAT, glucose tolerance, insulin-regulated hepatic glucose production, and cold tolerance. However, loss of FOXOs only partially rescued subcutaneous WAT and hepatosteatosis, did not rescue perigonadal WAT or systemic insulin resistance, and led to even more marked hyperinsulinemia. Thus, FOXOs play different roles in insulin/IGF-1 action in different adipose depots, being most important in BAT, followed by subcutaneous WAT and then by visceral WAT. Disruption of FOXOs in fat also led to a reversal of insulin resistance in liver, but not in skeletal muscle, and an exacerbation of hyperinsulinemia. Thus, adipose FOXOs play a unique role in regulating crosstalk between adipose depots, liver, and β cells.
Erica P. Homan, Bruna B. Brandão, Samir Softic, Abdelfattah El Ouaamari, Brian T. O’Neill, Rohit N. Kulkarni, Jason K. Kim, C. Ronald Kahn
Proper metabolic activities facilitate T cell expansion and antitumor function; however, the mechanisms underlying disruption of the T cell metabolic program and function in the tumor microenvironment (TME) remain elusive. Here, we show a zinc finger protein 91–governed (ZFP91-governed) mechanism that disrupts the metabolic pathway and antitumor activity of tumor-infiltrating T cells. Single-cell RNA-Seq revealed that impairments in T cell proliferation and activation correlated with ZFP91 in tissue samples from patients with colorectal cancer. T cell–specific deletion of Zfp91 in mice led to enhanced T cell proliferation and potentiated T cell antitumor function. Loss of ZFP91 increased mammalian target of rapamycin complex 1 (mTORC1) activity to drive T cell glycolysis. Mechanistically, T cell antigen receptor–dependent (TCR-dependent) ZFP91 cytosolic translocation promoted protein phosphatase 2A (PP2A) complex assembly, thereby restricting mTORC1-mediated metabolic reprogramming. Our results demonstrate that ZFP91 perturbs T cell metabolic and functional states in the TME and suggest that targeting ZFP91 may improve the efficacy of cancer immunotherapy.
Feixiang Wang, Yuerong Zhang, Xiaoyan Yu, Xiao-Lu Teng, Rui Ding, Zhilin Hu, Aiting Wang, Zhengting Wang, Youqiong Ye, Qiang Zou
NKTR-255 is a PEG conjugate of recombinant human IL-15 (rhIL-15) being examined as a potential cancer immunotherapeutic. Since IL-15 responses can be mediated by trans or cis presentation via IL-15Rα or soluble IL-15/IL-15Rα complexes, we investigated the role of IL-15Rα in driving NKTR-255 responses using defined naive and memory OVA-specific CD8+ T cells (OT-I) and NK cells in mice. NKTR-255 induced a 2.5- and 2.0-fold expansion of CD8+ T and NK cells, respectively, in WT mice. In adoptive transfer studies, proliferation of naive and memory WT OT-I T cells in response to NKTR-255 was not impaired in IL-15Rα−/− mice, suggesting trans presentation was not utilized by NKTR-255. Interestingly, naive IL-15Rα−/− OT-I cells had deficient responses to NKTR-255, while memory IL-15Rα−/− OT-I cell responses were partially impaired, suggesting that naive CD8+ T cells are more dependent on cis presentation of NKTR-255 than memory CD8+ T cells. In bone marrow chimera studies, IL-15Rα−/− and WT NK cells present in WT recipients had similar responses to NKTR-255, suggesting that cis presentation is not utilized by NK cells. NKTR-255 could form soluble complexes with IL-15Rα; binding to murine IL-15Rα generated superagonists that preferentially stimulated NK cells, showing that conversion to IL-15Rβ agonist biases the response toward NK cells. These findings highlight the ability of NKTR-255 to utilize IL-15Rα for cis presentation and act as an IL-15Rαβ agonist on CD8+ T cells.
Tanya O. Robinson, Shweta M. Hegde, Allison Chang, Achintyan Gangadharan, Sarai Rivas, Loui Madakamutil, Jonathan Zalevsky, Takahiro Miyazaki, Kimberly S. Schluns
Liver tumor-initiating cells (TICs) are involved in liver tumorigenesis, metastasis, drug resistance, and relapse, but the regulatory mechanisms of liver TICs are largely unknown. Here, we have identified a functional circular RNA, termed circRNA activating MAFF (cia-MAF), that is robustly expressed in liver cancer and liver TICs. cia-MAF–KO primary cells and cia-maf–KO liver tumors harbor decreased ratios of TICs, and display impaired liver tumorigenesis, self-renewal, and metastatic capacities. In contrast, cia-MAF overexpression drives liver TIC propagation, self-renewal, and metastasis. Mechanistically, cia-MAF binds to the MAFF promoter, recruits the TIP60 complex to the MAFF promoter, and finally promotes MAFF expression. Loss of cia-MAF function attenuates the combination between the TIP60 complex and the MAFF promoter. MAFF is highly expressed in liver tumors and liver TICs, and its antisense oligo (ASO) has therapeutic potential in treating liver cancer without MAFA/MAFG gene copy number alterations (CNAs). This study reveals an additional layer for liver TIC regulation as well as circRNA function, and provides an additional target for eliminating liver TICs, especially for liver tumors without MAFA/MAFG gene CNAs.
There is an urgent need to identify the cellular and molecular mechanisms responsible for severe COVID-19 that results in death. We initially performed both untargeted and targeted lipidomics as well as focused biochemical analyses of 127 plasma samples and found elevated metabolites associated with secreted phospholipase A2 (sPLA2) activity and mitochondrial dysfunction in patients with severe COVID-19. Deceased COVID-19 patients had higher levels of circulating, catalytically active sPLA2 group IIA (sPLA2-IIA), with a median value that was 9.6-fold higher than that for patients with mild disease and 5.0-fold higher than the median value for survivors of severe COVID-19. Elevated sPLA2-IIA levels paralleled several indices of COVID-19 disease severity (e.g., kidney dysfunction, hypoxia, multiple organ dysfunction). A decision tree generated by machine learning identified sPLA2-IIA levels as a central node in the stratification of patients who died from COVID-19. Random forest analysis and least absolute shrinkage and selection operator–based (LASSO-based) regression analysis additionally identified sPLA2-IIA and blood urea nitrogen (BUN) as the key variables among 80 clinical indices in predicting COVID-19 mortality. The combined PLA-BUN index performed significantly better than did either one alone. An independent cohort (n = 154) confirmed higher plasma sPLA2-IIA levels in deceased patients compared with levels in plasma from patients with severe or mild COVID-19, with the PLA-BUN index–based decision tree satisfactorily stratifying patients with mild, severe, or fatal COVID-19. With clinically tested inhibitors available, this study identifies sPLA2-IIA as a therapeutic target to reduce COVID-19 mortality.
Justin M. Snider, Jeehyun Karen You, Xia Wang, Ashley J. Snider, Brian Hallmark, Manja M. Zec, Michael C. Seeds, Susan Sergeant, Laurel Johnstone, Qiuming Wang, Ryan Sprissler, Tara F. Carr, Karen Lutrick, Sairam Parthasarathy, Christian Bime, Hao Helen Zhang, Chiara Luberto, Richard R. Kew, Yusuf A. Hannun, Stefano Guerra, Charles E. McCall, Guang Yao, Maurizio Del Poeta, Floyd H. Chilton
Epithelial cells are charged with protection at barrier sites, but whether this normally beneficial response might sometimes become dysfunctional still needs definition. Here, we recognized a pattern of imbalance marked by basal epithelial cell growth and differentiation that replaced normal airspaces in a mouse model of progressive postviral lung disease due to the Sendai virus. Single-cell and lineage-tracing technologies identified a distinct subset of basal epithelial stem cells (basal ESCs) that extended into gas-exchange tissue to form long-term bronchiolar-alveolar remodeling regions. Moreover, this cell subset was selectively expanded by crossing a cell-growth and survival checkpoint linked to the nuclear-localized alarmin IL-33 that was independent of IL-33 receptor signaling and instead connected to autocrine chromatin accessibility. This mechanism creates an activated stem-progenitor cell lineage with potential for physiological or pathological function. Thus, conditional loss of Il33 gene function in basal epithelial cells disrupted the homeostasis of the epithelial barrier at skin and gut sites but also markedly attenuated postviral disease in the lung based on the downregulation of remodeling and inflammation. Thus, we define a basal ESC strategy to deploy innate immune machinery that appears to overshoot the primordial goal of self-defense. Our findings reveal new targets to stratify and correct chronic and often deadly postviral disease.
Kangyun Wu, Kenji Kamimoto, Yong Zhang, Kuangying Yang, Shamus P. Keeler, Benjamin J. Gerovac, Eugene V. Agapov, Stephen P. Austin, Jennifer Yantis, Kelly A. Gissy, Derek E. Byers, Jennifer Alexander-Brett, Christy M. Hoffmann, Matthew Wallace, Michael E. Hughes, Erika C. Crouch, Samantha A. Morris, Michael J. Holtzman
BACKGROUND Chimeric antigen receptor (CAR) T cells have emerged as an approach to treat malignant tumors. This strategy has also been proposed for the treatment of HIV-1 infection. We have developed a broadly neutralizing antibody–derived (bNAb-derived) CAR T cell therapy that can exert specific cytotoxic activity against HIV-1–infected cells.METHODS We conducted an open-label trial of the safety, side-effect profile, pharmacokinetic properties, and antiviral activity of bNAb-derived CAR T cell therapy in individuals infected with HIV-1 who were undergoing analytical interruption of antiretroviral therapy (ART).RESULTS A total of 14 participants completed only a single administration of bNAb-derived CAR T cells. CAR T cell therapy administration was safe and well tolerated. Six participants discontinued ART, and viremia rebound occurred in all of them, with a 5.3-week median time. Notably, the cell-associated viral RNA and intact proviruses decreased significantly after CAR T cell treatment. Analyses of HIV-1 variants before or after CAR T cell administration suggested that CAR T cells exerted pressure on rebound viruses, resulting in a selection of viruses with less diversity and mutations against CAR T cell–mediated cytotoxicity.CONCLUSION No safety concerns were identified with adoptive transfer of bNAb-derived CAR T cells. They reduced viral reservoir. All the rebounds were due to preexisting or emergence of viral escape mutations.TRIAL REGISTRATION ClinicalTrials.gov (NCT03240328).FUNDING Ministry of Science and Technology of China, National Natural Science Foundation of China, and Department of Science and Technology of Guangdong Province.
The secreted protein developmental endothelial locus 1 (DEL-1) regulates inflammatory cell recruitment and protects against inflammatory pathologies in animal models. Here, we investigated DEL-1 in inflammatory arthritis using collagen-induced arthritis (CIA) and collagen Ab–induced arthritis (CAIA) models. In both models, mice with endothelium-specific overexpression of DEL-1 were protected from arthritis relative to WT controls, whereas arthritis was exacerbated in DEL-1–deficient mice. Compared with WT controls, mice with collagen VI promoter–driven overexpression of DEL-1 in mesenchymal cells were protected against CIA but not CAIA, suggesting a role for DEL-1 in the induction of the arthritogenic Ab response. Indeed, DEL-1 was expressed in perivascular stromal cells of the lymph nodes and inhibited Tfh and germinal center B cell responses. Mechanistically, DEL-1 inhibited DC-dependent induction of Tfh cells by targeting the LFA-1 integrin on T cells. Overall, DEL-1 restrained arthritis through a dual mechanism, one acting locally in the joints and associated with the anti-recruitment function of endothelial cell–derived DEL-1; the other mechanism acting systemically in the lymph nodes and associated with the ability of stromal cell–derived DEL-1 to restrain Tfh responses. DEL-1 may therefore be a promising therapeutic for the treatment of inflammatory arthritis.
Hui Wang, Xiaofei Li, Tetsuhiro Kajikawa, Jieun Shin, Jong-Hyung Lim, Ioannis Kourtzelis, Kosuke Nagai, Jonathan M. Korostoff, Sylvia Grossklaus, Ronald Naumann, Triantafyllos Chavakis, George Hajishengallis
BACKGROUND The loss of insulin-like growth factor 1 (IGF-1) expression in senescent dermal fibroblasts during aging is associated with an increased risk of nonmelanoma skin cancer (NMSC). We tested how IGF-1 signaling can influence photocarcinogenesis during chronic UVB exposure to determine if fractionated laser resurfacing (FLR) of aged skin, which upregulates dermal IGF-1 levels, can prevent the occurrence of actinic keratosis (AK) and NMSC.METHODS A human skin/immunodeficient mouse xenografting model was used to test the effects of a small molecule inhibitor of the IGF-1 receptor on chronic UVB radiation. Subsequently, the durability of FLR treatment was tested on a cohort of human participants aged 65 years and older. Finally, 48 individuals aged 60 years and older with considerable actinic damage were enrolled in a prospective randomized clinical trial in which they underwent a single unilateral FLR treatment of one lower arm. Numbers of AKs/NMSCs were recorded on both extremities for up to 36 months in blinded fashion.RESULTS Xenografting studies revealed that chronic UVB treatment with a topical IGF-1R inhibitor resulted in a procarcinogenic response. A single FLR treatment was durable in restoring appropriate UVB response in geriatric skin for at least 2 years. FLR resulted in sustained reduction in numbers of AKs and decreased numbers of NMSCs in the treated arm (2 NMSCs) versus the untreated arm (24 NMSCs).CONCLUSION The elimination of senescent fibroblasts via FLR reduced the procarcinogenic UVB response of aged skin. Thus, wounding therapies are a potentially effective prophylaxis for managing high-risk populations.TRIAL REGISTRATION ClinicalTrials.gov (NCT03906253).FUNDING National Institutes of Health, Veterans Administration.
Dan F. Spandau, Roy Chen, Jeffrey J. Wargo, Craig A. Rohan, David Southern, Angela Zhang, Mathew Loesch, Jonathan Weyerbacher, Sunil S. Tholpady, Davina A. Lewis, Matthew Kuhar, Kenneth Y. Tsai, Amber J. Castellanos, Michael G. Kemp, Michael Markey, Elizabeth Cates, Amy R. Williams, Christina Knisely, Sabina Bashir, Ryan Gabbard, Robert Hoopes, Jeffrey B. Travers
BACKGROUND The angiotensin-converting enzyme (ACE) D allele is more prevalent among African Americans compared with other races and ethnicities and has previously been associated with severe coronavirus disease 2019 (COVID-19) pathogenesis through excessive ACE1 activity. ACE inhibitors/angiotensin receptor blockers (ACE-I/ARB) may counteract this mechanism, but their association with COVID-19 outcomes has not been specifically tested in the African American population.METHODS We identified 6218 patients who were admitted into Mount Sinai hospitals with COVID-19 between February 24 and May 31, 2020, in New York City. We evaluated whether the outpatient and in-hospital use of ACE-I/ARB is associated with COVID-19 in-hospital mortality in an African American compared with non–African American population.RESULTS Of the 6218 patients with COVID-19, 1138 (18.3%) were ACE-I/ARB users. In a multivariate logistic regression model, ACE-I/ARB use was independently associated with a reduced risk of in-hospital mortality in the entire population (OR, 0.655; 95% CI, 0.505–0.850; P = 0.001), African American population (OR, 0.44; 95% CI, 0.249–0.779; P = 0.005), and non–African American population (OR, 0.748, 95% CI, 0.553–1.012, P = 0.06). In the African American population, in-hospital use of ACE-I/ARB was associated with improved mortality (OR, 0.378; 95% CI, 0.188–0.766; P = 0.006), whereas outpatient use was not (OR, 0.889; 95% CI, 0.375–2.158; P = 0.812). When analyzing each medication class separately, ARB in-hospital use was significantly associated with reduced in-hospital mortality in the African American population (OR, 0.196; 95% CI, 0.074–0.516; P = 0.001), whereas ACE-I use was not associated with impact on mortality in any population.CONCLUSION In-hospital use of ARB was associated with a significant reduction in in-hospital mortality among COVID-19–positive African American patients.FUNDING None.
Shilong Li, Rangaprasad Sarangarajan, Tomi Jun, Yu-Han Kao, Zichen Wang, Ke Hao, Emilio Schadt, Michael A. Kiebish, Elder Granger, Niven R. Narain, Rong Chen, Eric E. Schadt, Li Li
BACKGROUND Clinical data to support the use of bamlanivimab for the treatment of outpatients with mild to moderate coronavirus disease-19 (COVID-19) are needed.METHODS 2335 Patients who received single-dose bamlanivimab infusion between November 12, 2020, and February 17, 2021, were compared with a propensity-matched control of 2335 untreated patients with mild to moderate COVID-19 at Mayo Clinic facilities across 4 states. The primary outcome was the rate of hospitalization at days 14, 21, and 28.RESULTS The median age of the population was 63 years; 47.3% of the bamlanivimab-treated cohort were 65 years or more; 49.3% were female and 50.7% were male. High-risk characteristics included hypertension (54.2%), BMI greater than or equal to 35 (32.4%), diabetes mellitus (26.5%), chronic lung disease (25.1%), malignancy (16.6%), and renal disease (14.5%). Patients who received bamlanivimab had lower all-cause hospitalization rates at days 14 (1.5% vs. 3.5%; risk ratio [RR], 0.41), 21 (1.9% vs. 3.9%; RR, 0.49), and 28 (2.5% vs. 3.9%; RR, 0.63). Secondary exploratory outcomes included lower intensive care unit (ICU) admission rates at days 14 (0.14% vs. 1%; RR, 0.14), 21 (0.25% vs.1%; RR, 0.25), and 28 (0.56% vs.1.1%; RR. 0.51) and lower all-cause mortality at days 14 (0% vs. 0.33%), 21 (0.05% vs. 0.4%; RR,0.13), and 28 (0.11% vs. 0.44%; RR, 0.26). Adverse events were uncommon with bamlanivimab, occurring in 19 of 2355 patients, and were most commonly fever (n = 6), nausea (n = 5), and lightheadedness (n = 3).CONCLUSIONS Among high-risk patients with mild to moderate COVID-19, treatment with bamlanivimab was associated with a statistically significant lower rate of hospitalization, ICU admission, and mortality compared with usual care.FUNDING Mayo Clinic.
Ravindra Ganesh, Colin F. Pawlowski, John C. O’Horo, Lori L. Arndt, Richard F. Arndt, Sarah J. Bell, Dennis M. Bierle, Molly Destro Borgen, Sara N. Hanson, Alexander Heyliger, Jennifer J. Larsen, Patrick J. Lenehan, Robert Orenstein, Arjun Puranik, Leigh L. Speicher, Sidna M. Tulledge-Scheitel, A.J. Venkatakrishnan, Caroline G. Wilker, Andrew D. Badley, Raymund R. Razonable
Wenqing Li, Robert Shenkar, Mathew R. Detter, Thomas Moore, Christian Benavides, Rhonda Lightle, Romuald Girard, Nicholas Hobson, Ying Cao, Yan Li, Erin Griffin, Carol Gallione, Joseph M. Zabramski, Mark H. Ginsberg, Douglas A. Marchuk, Issam A. Awad
Although Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) vaccines have shown efficacy against SARS-CoV-2, it is unknown if coronavirus vaccines can also protect against other coronaviruses that may infect humans in the future. Here, we show that coronavirus vaccines elicit cross-protective immune responses against heterologous coronaviruses. In particular, we show that a Severe Acute Respiratory Syndrome Coronavirus 1 (SARS-CoV-1) vaccine developed in 2004 and known to protect against SARS-CoV-1, confers robust heterologous protection against SARS-CoV-2 in mice. Similarly, prior coronavirus infections conferred heterologous protection against distinct coronaviruses. Cross-reactive immunity was also reported in Coronavirus Disease 2019 (COVID-19) patients and humans who received SARS-CoV-2 vaccines, and transfer of plasma from these individuals into mice improved protection against coronavirus challenges. These findings provide the first demonstration that coronavirus vaccines (and prior coronavirus infections) can confer broad protection against heterologous coronaviruses, providing a rationale for universal coronavirus vaccines.
Tanushree Dangi, Nicole Palacio, Sarah Sanchez, Mincheol Park, Jake Class, Lavanya Visvabharathy, Thomas Ciucci, Igor J. Koralnik, Justin M. Richner, Pablo Penaloza-MacMaster
Central obesity with cardiometabolic syndrome (CMS) is a major global contributor to human disease, and effective therapies are needed. Here, we show inhibiting cyclic-GMP selective phosphodiesterase-9A (PDE9-I) in both ovariectomized female or male mice suppresses pre-established severe diet-induced obesity/CMS with or without superimposed mild cardiac pressure-load. PDE9-I reduces total body, inguinal, hepatic, and myocardial fat, stimulating mitochondrial activity in brown and white fat, and improving CMS, without significantly altering activity or food intake. PDE9 localized at mitochondria, and its inhibition in vitro stimulated lipolysis and mitochondrial respiration in adipocytes and myocytes coupled to PPARα-dependent gene regulation. PPARα upregulation was required to achieve the lipolytic, anti-obesity, and metabolic effects of PDE9-I. All these PDE9-I induced changes were not observed in obese/CMS non-ovariectomized females, indicating a strong sexual dimorphism. We found that PPARα chromatin binding was re-oriented away from fat-metabolism regulating genes when stimulated in the presence of co-activated estrogen receptor-alpha, and this may underly the dimorphism. These findings have translational relevance given that PDE9-I is already being studied in humans for indications including heart failure, and efficacy against obesity/CMS would enhance its therapeutic utility.
Sumita Mishra, Nandhini Sadagopan, Brittany Dunkerly-Eyring, Susana Rodriguez, Dylan C. Sarver, Ryan P. Ceddia, Sean A. Murphy, Hildur Knutsdottir, Vivek P. Jani, Deepthi Ashok, Christian U. Oeing, Brian O'Rourke, Jon A. Gangoiti, Dorothy D. Sears, G. William Wong, Sheila Collins, David Kass
Human monoclonal antibodies were used here to study the mechanism of neuron intoxication by tetanus neurotoxin and to evaluate them as a safe preventive and therapeutic substitute of hyperimmune sera for tetanus in mice. By screening memory B cells of immune donors, we selected two monoclonal antibodies specific for tetanus neurotoxin with exceptionally high neutralizing activities, which were extensively characterized both structurally and functionally. We found that these antibodies interfere with the binding and translocation of the neurotoxin into neurons by interacting with two epitopes, whose definition pinpoints crucial events in the cellular pathogenesis of tetanus. This information explains the unprecedented neutralization ability of these antibodies, which were found to be exceptionally potent in preventing experimental tetanus when injected in mice long before the neurotoxin. Moreover, their Fab derivatives neutralized tetanus neurotoxin in post-exposure experiments, suggesting their potential therapeutic use via intrathecal injection. As such, these human monoclonal antibodies, as well as their Fab derivatives, meet all requirements for being considered for prophylaxis and therapy of human tetanus and are ready for clinical trials.
Marco Pirazzini, Alessandro Grinzato, Davide Corti, Sonia Barbieri, Oneda Leka, Francesca Vallese, Marika Tonellato, Chiara Silacci-Fregni, Luca Piccoli, Eaazhisai Kandiah, Giampietro Schiavo, Giuseppe Zanotti, Antonio Lanzavecchia, Cesare Montecucco
BACKGROUND. Gingivitis and periodontitis are prevalent inflammatory diseases of the periodontal tissues. Current treatments are often ineffective or do not prevent disease recurrence. Uncontrolled complement activation and resulting chronic gingival inflammation is a hallmark of periodontal diseases. We determined efficacy and safety of a complement 3-targeted therapeutic, AMY-101, locally administered in adults with periodontal inflammation. METHODS. Thirty-two patients with gingival inflammation were enrolled into a randomized, placebo-controlled, double-blind, split-mouth design phase 2a trial, after dose-escalation study to select safe and effective dose with additional 8 patients. Half of the mouth was randomly assigned to AMY-101 (0.1mg/site) or placebo injections at sites of inflammation, administered on days 0, 7 and 14 and evaluated for safety and efficacy outcomes at days 28, 60 and 90. The primary efficacy outcome was change in gingival inflammation, measured by modified gingival index (MGI), and secondary outcomes included changes in bleeding-on-probing (BOP), amount of plaque, pocket depth, clinical attachment level, and gingival crevicular fluid levels of matrix metalloproteinases (MMPs) over 90 days. RESULTS. A once-per-week intragingival injection of AMY-101 for 3 weeks was safe and well-tolerated in all participants resulting in significant (P<0.001) reductions in clinical indices measuring gingival inflammation (MGI and BOP). AMY-101 significantly (P<0.05) reduced MMP-8 and MMP-9 levels, indicators of inflammatory tissue destruction. These therapeutic effects persisted for at least 3 months post-treatment. CONCLUSION. AMY-101 causes significant and sustainable reduction in gingival inflammation without adverse events and merits further investigation for the treatment of periodontitis and other oral or peri-implant inflammatory conditions. TRIAL REGISTRATION. ClinicalTrials.gov: NCT03694444. FUNDING. Amyndas Pharmaceuticals. Amyndas contributed to the design and conducts of the clinical trial and in the writing of the manuscript.
Hatice Hasturk, George Hajishengallis, John D. Lambris, Dimitrios C. Mastellos, Despina Yancopoulou
Insulin resistance is a cornerstone of obesity related complications such as type 2 diabetes, metabolic syndrome, and non-alcoholic fatty liver disease. A high rate of lipolysis is known to be associated with insulin resistance, and inhibiting adipose tissue lipolysis improves obesity-related insulin resistance. Here, we demonstrate that inhibition of 5-HT signaling through serotonin receptor 2B (HTR2B) in adipose tissues ameliorates insulin resistance by reducing lipolysis in visceral adipocytes. Chronic high-fat diet (HFD) feeding increased Htr2b expression in eWAT, resulting in the increased HTR2B signaling in visceral white adipose tissue. Moreover, HTR2B expression in white adipose tissue was increased in obese humans and positively correlated with metabolic parameters. We further found that adipocyte-specific Htr2b-knockout mice are resistant to high-fat diet (HFD)-induced insulin resistance, visceral adipose tissue inflammation, and hepatic steatosis. Enhanced 5-HT signaling through HTR2B directly activated lipolysis through phosphorylation of hormone sensitive lipase in visceral adipocytes. Moreover, treatment with a selective HTR2B antagonist attenuated HFD-induced insulin resistance, visceral tissue inflammation, and hepatic steatosis. Thus, adipose HTR2B signaling could be a potential therapeutic target for treatment of obesity-related insulin resistance.
Animals, plants, and bacteria all display behavioral patterns that coincide with Earth’s light and dark cycles. These oscillating behaviors are the manifestation of the molecular circadian clock, a highly conserved network that maintains a near 24-hour rhythm even in the absence of light. In mammals, light signals are transmitted via the superchiasmatic nucleus (SCN) in the hypothalamus to synchronize peripheral clocks and coordinate physiological functions with the organism’s active period. This collection of reviews, curated by Amita Sehgal, considers the critical role of the circadian system in human health. Technology, work, and social obligations can disrupt optimal sleep and wake schedules, leaving humans vulnerable to diseases affecting the heart, brain, metabolism, and more. Sleep disorders as well as normal variations in human chronotype may exacerbate circadian disruptions, with profound consequences. These reviews emphasize that ongoing efforts to understand the complexities of human circadian rhythm will be essential for developing chronotherapies and other circadian-based interventions.