Research Article
Abstract
STAT2 is a transcription factor activated by type I and III IFNs. We report 23 patients with loss-of-function variants causing autosomal recessive (AR) complete STAT2 deficiency. Both cells transfected with mutant STAT2 alleles and the patients’ cells displayed impaired expression of IFN-stimulated genes and impaired control of in vitro viral infections. Clinical manifestations from early childhood onward included severe adverse reaction to live attenuated viral vaccines (LAV) and severe viral infections, particularly critical influenza pneumonia, critical COVID-19 pneumonia, and herpes simplex virus type 1 (HSV-1) encephalitis. The patients displayed various types of hyperinflammation, often triggered by viral infection or after LAV administration, which probably attested to unresolved viral infection in the absence of STAT2-dependent types I and III IFN immunity. Transcriptomic analysis revealed that circulating monocytes, neutrophils, and CD8+ memory T cells contributed to this inflammation. Several patients died from viral infection or heart failure during a febrile illness with no identified etiology. Notably, the highest mortality occurred during early childhood. These findings show that AR complete STAT2 deficiency underlay severe viral diseases and substantially impacts survival.
Authors
Giorgia Bucciol, Leen Moens, Masato Ogishi, Darawan Rinchai, Daniela Matuozzo, Mana Momenilandi, Nacim Kerrouche, Catherine M. Cale, Elsa R. Treffeisen, Mohammad Al Salamah, Bandar K. Al-Saud, Alain Lachaux, Remi Duclaux-Loras, Marie Meignien, Aziz Bousfiha, Ibtihal Benhsaien, Anna Shcherbina, Anna Roppelt, COVID Human Genetic Effort, Florian Gothe, Nadhira Houhou-Fidouh, Scott J. Hackett, Lisa M. Bartnikas, Michelle C. Maciag, Mohammed F. Alosaimi, Janet Chou, Reem W. Mohammed, Bishara J. Freij, Emmanuelle Jouanguy, Shen-Ying Zhang, Stephanie Boisson-Dupuis, Vivien Béziat, Qian Zhang, Christopher J.A. Duncan, Sophie Hambleton, Jean-Laurent Casanova, Isabelle Meyts
Abstract
Senescent vascular smooth muscle cells (VSMCs) accumulate in the vasculature with age and tissue damage and secrete factors that promote atherosclerotic plaque vulnerability and disease. Here, we report increased levels and activity of dipeptidyl peptidase 4 (DPP4), a serine protease, in senescent VSMCs. Analysis of the conditioned media from senescent VSMCs revealed a unique senescence-associated secretory phenotype (SASP) signature comprising many complement and coagulation factors; silencing or inhibiting DPP4 reduced these factors and increased cell death. Serum samples from persons with high risk for cardiovascular disease contained high levels of DPP4-regulated complement and coagulation factors. Importantly, DPP4 inhibition reduced senescent cell burden and coagulation and improved plaque stability, while single-cell resolution of senescent VSMCs reflected the senomorphic and senolytic effects of DPP4 inhibition in murine atherosclerosis. We propose that DPP4-regulated factors could be exploited therapeutically to reduce senescent cell function, reverse senohemostasis, and improve vascular disease.
Authors
Allison B. Herman, Dimitrios Tsitsipatis, Carlos Anerillas, Krystyna Mazan-Mamczarz, Angelica E. Carr, Jordan M. Gregg, Mingyi Wang, Jing Zhang, Marc Michel, Charnae’ A. Henry-Smith, Sophia C. Harris, Rachel Munk, Jennifer L. Martindale, Yulan Piao, Jinshui Fan, Julie A. Mattison, Supriyo De, Kotb Abdelmohsen, Robert W. Maul, Toshiko Tanaka, Ann Zenobia Moore, Megan E. DeMouth, Simone Sidoli, Luigi Ferrucci, Yie Liu, Rafael de Cabo, Edward G. Lakatta, Myriam Gorospe
Abstract
Patients with severe COVID-19 develop acute respiratory distress syndrome (ARDS) that may progress to cytokine storm syndrome, organ dysfunction, and death. Considering that complement component 5a (C5a), through its cellular receptor C5aR1, has potent proinflammatory actions and plays immunopathological roles in inflammatory diseases, we investigated whether the C5a/C5aR1 pathway could be involved in COVID-19 pathophysiology. C5a/C5aR1 signaling increased locally in the lung, especially in neutrophils of critically ill patients with COVID-19 compared with patients with influenza infection, as well as in the lung tissue of K18-hACE2 Tg mice (Tg mice) infected with SARS-CoV-2. Genetic and pharmacological inhibition of C5aR1 signaling ameliorated lung immunopathology in Tg-infected mice. Mechanistically, we found that C5aR1 signaling drives neutrophil extracellular traps-dependent (NETs-dependent) immunopathology. These data confirm the immunopathological role of C5a/C5aR1 signaling in COVID-19 and indicate that antagonists of C5aR1 could be useful for COVID-19 treatment.
Authors
Bruna M. Silva, Giovanni F. Gomes, Flavio P. Veras, Seppe Cambier, Gabriel V.L. Silva, Andreza U. Quadros, Diego B. Caetité, Daniele C. Nascimento, Camilla M. Silva, Juliana C. Silva, Samara Damasceno, Ayda H. Schneider, Fabio Beretta, Sabrina S. Batah, Icaro M.S. Castro, Isadora M. Paiva, Tamara Rodrigues, Ana Salina, Ronaldo Martins, Guilherme C.M. Cebinelli, Naira L. Bibo, Daniel M. Jorge, Helder I. Nakaya, Dario S. Zamboni, Luiz O. Leiria, Alexandre T. Fabro, José C. Alves-Filho, Eurico Arruda, Paulo Louzada-Junior, Renê D. Oliveira, Larissa D. Cunha, Pierre Van Mol, Lore Vanderbeke, Simon Feys, Els Wauters, Laura Brandolini, Andrea Aramini, Fernando Q. Cunha, Jörg Köhl, Marcello Allegretti, Diether Lambrechts, Joost Wauters, Paul Proost, Thiago M. Cunha
Abstract
The ADP ribosyltransferases (PARPs 1–17) regulate diverse cellular processes, including DNA damage repair. PARPs are classified on the basis of their ability to catalyze poly-ADP-ribosylation (PARylation) or mono-ADP-ribosylation (MARylation). Although PARP9 mRNA expression is significantly increased in progressive tuberculosis (TB) in humans, its participation in host immunity to TB is unknown. Here, we show that PARP9 mRNA encoding the MARylating PARP9 enzyme was upregulated during TB in humans and mice and provide evidence of a critical modulatory role for PARP9 in DNA damage, cyclic GMP–AMP synthase (cGAS) expression, and type I IFN production during TB. Thus, Parp9-deficient mice were susceptible to Mycobacterium tuberculosis infection and exhibited increased TB disease, cGAS and 2′3′-cyclic GMP-AMP (cGAMP) expression, and type I IFN production, along with upregulation of complement and coagulation pathways. Enhanced M. tuberculosis susceptibility is type I IFN dependent, as blockade of IFN α receptor (IFNAR) signaling reversed the enhanced susceptibility of Parp9–/– mice. Thus, in sharp contrast to PARP9 enhancement of type I IFN production in viral infections, this member of the MAR family plays a protective role by limiting type I IFN responses during TB.
Authors
Shyamala Thirunavukkarasu, Mushtaq Ahmed, Bruce A. Rosa, Mark Boothby, Sung Hoon Cho, Javier Rangel-Moreno, Stanley K. Mbandi, Valérie Schreiber, Ananya Gupta, Joaquin Zuniga, Makedonka Mitreva, Deepak Kaushal, Thomas J. Scriba, Shabaana A. Khader
Abstract
Brain microglia (MG) may serve as a human immunodeficiency virus 1 (HIV) reservoir and ignite rebound viremia following cessation of antiretroviral therapy (ART), but they have yet to be proven to harbor replication-competent HIV. Here, we isolated brain myeloid cells (BrMCs) from nonhuman primates and rapid autopsy of people with HIV (PWH) on ART and sought evidence of persistent viral infection. BrMCs predominantly displayed microglial markers, in which up to 99.9% of the BrMCs were TMEM119+ MG. Total and integrated SIV or HIV DNA was detectable in the MG, with low levels of cell-associated viral RNA. Provirus in MG was highly sensitive to epigenetic inhibition. Outgrowth virus from parietal cortex MG in an individual with HIV productively infected both MG and PBMCs. This inducible, replication-competent virus and virus from basal ganglia proviral DNA were closely related but highly divergent from variants in peripheral compartments. Phenotyping studies characterized brain-derived virus as macrophage tropic based on the ability of the virus to infect cells expressing low levels of CD4. The lack of genetic diversity in virus from the brain suggests that this macrophage-tropic lineage quickly colonized brain regions. These data demonstrate that MG harbor replication-competent HIV and serve as a persistent reservoir in the brain.
Authors
Yuyang Tang, Antoine Chaillon, Sara Gianella, Lilly M. Wong, Dajiang Li, Theresa L. Simermeyer, Magali Porrachia, Caroline Ignacio, Brendon Woodworth, Daniel Zhong, Jiayi Du, Eduardo de la Parra Polina, Jennifer Kirchherr, Brigitte Allard, Matthew L. Clohosey, Matt Moeser, Amy L. Sondgeroth, Gregory D. Whitehill, Vidisha Singh, Amir Dashti, Davey M. Smith, Joseph J. Eron, Katherine J. Bar, Ann Chahroudi, Sarah B. Joseph, Nancie M. Archin, David M. Margolis, Guochun Jiang
Abstract
RAS mutations are among the most prevalent oncogenic drivers in cancers. RAS proteins propagate signals only when associated with cellular membranes as a consequence of lipid modifications that impact their trafficking. Here, we discovered that RAB27B, a RAB family small GTPase, controlled NRAS palmitoylation and trafficking to the plasma membrane, a localization required for activation. Our proteomic studies revealed RAB27B upregulation in CBL- or JAK2-mutated myeloid malignancies, and its expression correlated with poor prognosis in acute myeloid leukemias (AMLs). RAB27B depletion inhibited the growth of CBL-deficient or NRAS-mutant cell lines. Strikingly, Rab27b deficiency in mice abrogated mutant but not WT NRAS–mediated progenitor cell growth, ERK signaling, and NRAS palmitoylation. Further, Rab27b deficiency significantly reduced myelomonocytic leukemia development in vivo. Mechanistically, RAB27B interacted with ZDHHC9, a palmitoyl acyltransferase that modifies NRAS. By regulating palmitoylation, RAB27B controlled c-RAF/MEK/ERK signaling and affected leukemia development. Importantly, RAB27B depletion in primary human AMLs inhibited oncogenic NRAS signaling and leukemic growth. We further revealed a significant correlation between RAB27B expression and sensitivity to MEK inhibitors in AMLs. Thus, our studies presented a link between RAB proteins and fundamental aspects of RAS posttranslational modification and trafficking, highlighting future therapeutic strategies for RAS-driven cancers.
Authors
Jian-Gang Ren, Bowen Xing, Kaosheng Lv, Rachel A. O’Keefe, Mengfang Wu, Ruoxing Wang, Kaylyn M. Bauer, Arevik Ghazaryan, George M. Burslem, Jing Zhang, Ryan M. O’Connell, Vinodh Pillai, Elizabeth O. Hexner, Mark R. Philips, Wei Tong
An allosteric inhibitor of sirtuin 2 deacetylase activity exhibits broad-spectrum antiviral activity
Abstract
Most drugs used to treat viral disease target a virus-coded product. They inhibit a single virus or virus family, and the pathogen can readily evolve resistance. Host-targeted antivirals can overcome these limitations. The broad-spectrum activity achieved by host targeting can be especially useful in combating emerging viruses and for treatment of diseases caused by multiple viral pathogens, such as opportunistic agents in immunosuppressed patients. We have developed a family of compounds that modulate sirtuin 2, an NAD+-dependent deacylase, and now report the properties of a member of that family, FLS-359. Biochemical and x-ray structural studies show that the drug binds to sirtuin 2 and allosterically inhibits its deacetylase activity. FLS-359 inhibits the growth of RNA and DNA viruses, including members of the coronavirus, orthomyxovirus, flavivirus, hepadnavirus, and herpesvirus families. FLS-359 acts at multiple levels to antagonize cytomegalovirus replication in fibroblasts, causing modest reductions in viral RNAs and DNA, together with a much greater reduction in infectious progeny, and it exhibits antiviral activity in humanized mouse models of infection. Our results highlight the potential of sirtuin 2 inhibitors as broad-spectrum antivirals and set the stage for further understanding of how host epigenetic mechanisms impact the growth and spread of viral pathogens.
Authors
Kathryn L. Roche, Stacy Remiszewski, Matthew J. Todd, John L. Kulp III, Liudi Tang, Alison V. Welsh, Ashley P. Barry, Chandrav De, William W. Reiley, Angela Wahl, J. Victor Garcia, Micah A. Luftig, Thomas Shenk, James R. Tonra, Eain A. Murphy, Lillian W. Chiang
Abstract
Genetic testing is essential for patients with a suspected hereditary myopathy. More than 50% of patients clinically diagnosed with a myopathy carry a variant of unknown significance in a myopathy gene, often leaving them without a genetic diagnosis. Limb-girdle muscular dystrophy (LGMD) type R4/2E is caused by mutations in β-sarcoglycan (SGCB). Together, β-, α-, γ-, and δ-sarcoglycan form a 4-protein transmembrane complex (SGC) that localizes to the sarcolemma. Biallelic loss-of-function mutations in any subunit can lead to LGMD. To provide functional evidence for the pathogenicity of missense variants, we performed deep mutational scanning of SGCB and assessed SGC cell surface localization for all 6,340 possible amino acid changes. Variant functional scores were bimodally distributed and perfectly predicted pathogenicity of known variants. Variants with less severe functional scores more often appeared in patients with slower disease progression, implying a relationship between variant function and disease severity. Amino acid positions intolerant to variation mapped to points of predicted SGC interactions, validated in silico structural models, and enabled accurate prediction of pathogenic variants in other SGC genes. These results will be useful for clinical interpretation of SGCB variants and improving diagnosis of LGMD; we hope they enable wider use of potentially life-saving gene therapy.
Authors
Chengcheng Li, Jackson Wilborn, Sara Pittman, Jil Daw, Jorge Alonso-Pérez, Jordi Díaz-Manera, Conrad C. Weihl, Gabe Haller
Abstract
While the rapid advancement of immunotherapies has revolutionized cancer treatment, only a small fraction of patients derive clinical benefit. Eradication of large, established tumors appears to depend on engaging and activating both innate and adaptive immune system components to mount a rigorous and comprehensive immune response. Identifying such agents is a high unmet medical need, because they are sparse in the therapeutic landscape of cancer treatment. Here, we report that IL-36 cytokine can engage both innate and adaptive immunity to remodel an immune-suppressive tumor microenvironment (TME) and mediate potent antitumor immune responses via signaling in host hematopoietic cells. Mechanistically, IL-36 signaling modulates neutrophils in a cell-intrinsic manner to greatly enhance not only their ability to directly kill tumor cells but also promote T and NK cell responses. Thus, while poor prognostic outcomes are typically associated with neutrophil enrichment in the TME, our results highlight the pleiotropic effects of IL-36 and its therapeutic potential to modify tumor-infiltrating neutrophils into potent effector cells and engage both the innate and adaptive immune system to achieve durable antitumor responses in solid tumors.
Authors
Sumedha Roy, Karen Fitzgerald, Almin Lalani, Chin-Wen Lai, Aeryon Kim, Jennie Kim, Peiqi Ou, Annie Mirsoian, Xian Liu, Ambika Ramrakhiani, Huiren Zhao, Hong Zhou, Haoda Xu, Hans Meisen, Chi-Ming Li, Bryan Vander Lugt, Steve Thibault, Christine E. Tinberg, Jason DeVoss, Jackson Egen, Lawren C. Wu, Rajkumar Noubade
Abstract
Microglia are the major cell type expressing complement C3a receptor (C3aR) in the brain. Using a knockin mouse line in which a Td-tomato reporter is incorporated into the endogenous C3ar1 locus, we identified 2 major subpopulations of microglia with differential C3aR expression. Expressing the Td-tomato reporter on the APPNL-G-F–knockin (APP-KI) background revealed a significant shift of microglia to a high-C3aR-expressing subpopulation and they were enriched around amyloid β (Aβ) plaques. Transcriptomic analysis of C3aR-positive microglia documented dysfunctional metabolic signatures, including upregulation of hypoxia-inducible factor 1 (HIF-1) signaling and abnormal lipid metabolism in APP-KI mice compared with wild-type controls. Using primary microglial cultures, we found that C3ar1-null microglia had lower HIF-1α expression and were resistant to hypoxia mimetic–induced metabolic changes and lipid droplet accumulation. These were associated with improved receptor recycling and Aβ phagocytosis. Crossing C3ar1-knockout mice with the APP-KI mice showed that C3aR ablation rescued the dysregulated lipid profiles and improved microglial phagocytic and clustering abilities. These were associated with ameliorated Aβ pathology and restored synaptic and cognitive function. Our studies identify a heightened C3aR/HIF-1α signaling axis that influences microglial metabolic and lipid homeostasis in Alzheimer disease, suggesting that targeting this pathway may offer therapeutic benefit.
Authors
Manasee Gedam, Michele M. Comerota, Nicholas E. Propson, Tao Chen, Feng Jin, Meng C. Wang, Hui Zheng
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ISSN: 0021-9738 (print), 1558-8238 (online)