Immunology
Abstract
Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) is the leading infectious cause of death globally. Despite wide use of antiretroviral therapy (ART) by people living with HIV, the risk of TB remains increased. To understand immune interactions within lung granulomas, we compared spatial transcriptomics of Mtb and simian immunodeficiency virus (SIV) in co-infected macaques with or without ART as a model for HIV/Mtb co-infection. Spatially differentiated transcriptional profiles were observed in Mtb-only granulomas, with myeloid cells enriched in metabolic/antimicrobial pathways within the inner ring and T cell co-stimulatory/activation pathways enriched in the outer ring. These spatially distinct patterns were lost in SIV/Mtb granulomas with higher enrichment in type I IFN pathways compared to Mtb-only granulomas. SIV/ART/Mtb granulomas had an intermediate transcriptional pattern without restoration to Mtb-only granulomas, despite a lack of viral replication. Cell-cell communication was reduced among SIV/Mtb co-infected groups. These data suggest that HIV disrupts spatially organized immune functions of granulomas, which are not fully restored by ART.
Authors
Jessica M. Medrano, Persis Sunny, Collin R. Diedrich, Pauline Maiello, Christopher Kline, Tara Rutledge, Edwin Klein, Joshua T. Mattila, Jishnu Das, Zandrea Ambrose, Philana Ling Lin
Abstract
BACKGROUND. This prospective, single-arm, multicenter phase 1/2 trial evaluated vorinostat added to standard graft-versus-host disease (GVHD) prophylaxis in pediatric, adolescent, and young adult (AYA) patients undergoing allogeneic hematopoietic cell transplantation (HCT) from HLA-matched related, HLA-matched unrelated, and haploidentical donors. METHODS. Patients aged 3–39 years received twice-daily vorinostat with tacrolimus/methotrexate after HLA-matched HCT from day −10 to +30, or with post-transplant cyclophosphamide/tacrolimus/mycophenolate mofetil after haploidentical HCT from day +5 to +30. The primary endpoint was cumulative incidence of grade II–IV acute GVHD by day +100. All outcomes were based on intention-to-treat analysis. RESULTS. Forty-three patients were enrolled; median age was 19 years, with 74% receiving HLA-matched and 26% haploidentical HCT. The recommended phase 2 dose was 60 mg/m² twice daily. No dose-limiting toxicities, unexpected vorinostat-related serious adverse events, or primary graft failures occurred. Median neutrophil and platelet recovery occurred at 14 and 18 days, respectively. Day +100 grade II–IV and III–IV acute GVHD were 14% (95% CI, 5.6, 26) and 4.7% (95% CI, 0.83, 14), respectively. One-year overall survival was 88.4% (95% CI, 79.3, 98.5), relapse 14% (95% CI: 5.6, 26), nonrelapse mortality 4.7% (95% CI: 0.8, 14), and GVHD-free/relapse-free survival 55.8% (95% CI: 42.8, 72.8). Correlative studies demonstrated on-target HDAC activity, with increased histone acetylation and lower proinflammatory cytokines. CONCLUSION. These findings support randomized evaluation of vorinostat-based GVHD prophylaxis in pediatric and AYA HCT. TRIAL REGISTRY. ClinicalTrials.gov, NCT03842696.
Authors
Nicolas Parnell, Xiao Cao, Jan H. Beumer, Thomas M. Braun, Yilei Cui, Gary J. Fisher, Guoqing Hou, Julianne Holleran, Tracey Churay, Michelle Rozwadowski, Luna Heider, Mark T. Vander Lugt, Carrie L. Kitko, April L. Rahrig, Ed Peres, Kirsten M. Williams, Julie-An Talano, Vanessa A. Fabrizio, Ghada Abusin, Gregory A. Yanik, John Magenau, Mary Riwes, Marcus J. Geer, Sarah Anand, Monalisa Ghosh, Attaphol Pawarode, Kristen Votruba, Pavan Reddy, Sung Won Choi
Abstract
Patients who survive sepsis are predisposed to new hospitalizations for respiratory failure, but the underlying mechanisms are unknown. Using a murine model in which prior sepsis predisposes to enhanced lung injury, we previously discovered that classical monocytes persist in the lungs after long-term recovery from sepsis and exhibit enhanced cytokine expression after secondary challenge with intra-nasal lipopolysaccharide. Here, we hypothesized that immune reprogramming of post-sepsis monocytes and altered ontogeny predispose to enhanced lung injury. Monocyte depletion and/or adoptive transfer was performed three weeks and three months after sepsis. Monocytes from post-sepsis mice were necessary and sufficient for enhanced LPS-induced lung injury and promoted neutrophil degranulation. Prior sepsis enhanced JAK-STAT signaling and AP-1 accessibility in monocytes and shifted monocytes toward the neutrophil-like monocyte lineage. Neutrophil-like monocytes demonstrated a pro-inflammatory phenotype with enhanced IL-1β expression and reduced phagocytic capacity. In human sepsis and/or pneumonia survivors, monocytes were predictive of 90-day mortality and exhibit transcriptional and proteomic neutrophil-like signatures. We conclude that sepsis reprograms monocytes into a pro-inflammatory phenotype and skews bone marrow progenitors and monocytes toward the neutrophil-like lineage, predisposing them to induce neutrophil degranulation and lung injury.
Authors
Scott J. Denstaedt, Breanna McBean, Alan P. Boyle, Brett C. Arenberg, Matthias Mack, Bethany B. Moore, Michael W. Newstead, Yamei Deng, Alexey I. Nesvizhskii, Benjamin H. Singer, Jennifer Cano, Hallie C. Prescott, Helen S. Goodridge, Rachel L. Zemans
Abstract
Early antiretroviral therapy (ART) limits viral reservoir establishment in infants but also constrains viral-specific immunity required to clear reactivated cells. In the early ART context, we evaluated whether combining adeno-associated virus serotype 9 (AAV9)–vectored eCD4-IgG1 with pharmacologic latency reversal using the second mitochondria-derived activator of caspases (SMAC) mimetic AZD5582 could promote reservoir reduction and control in simian immunodeficiency virus (SIV)–infected infant macaques. AAV9 delivery achieved sustained eCD4-IgG1 expression and AZD5582 induced on-ART viremia, but the combination did not reduce intact SIV proviral DNA relative to controls. Partial post-intervention control of viremia during Analytical Treatment Interruption (ATI) occurred in 2/6 infants receiving AAV9-eCD4-IgG1 + AZD5582 with restricted reservoir expansion during recrudescence at week 13. Intact reservoir size during ATI correlated inversely with on-ART viremia during AZD5582 treatment. Controllers did not show increased eCD4-IgG1 expression nor increased on-ART viremia during AZD5582 treatment, but harbored less pre-ART intact SIV DNA in PBMCs than non-controllers. Controllers also exhibited higher frequencies and greater polyfunctionality of virus-specific CD8+ T-cells prior to ATI. These findings implicate immune control of reservoir size and post-ART viral dynamics in early-treated infants and suggest that AAV9-eCD4-IgG1 + AZD5582 increases the likelihood of post-ART viral control.
Authors
Jairo A. Fonseca, Alexis C. King, Kaleaha S. Davis, Daniel O'Hagan, Adrian Khoei, Lucas Alves Britto Da Costa, Camryn Cockerham, Mackenzie Cottrell, Stephanie Ehnert, Jennifer S. Wood, Michael D. Alpert, Matthew R. Gardner, Jeffrey D. Lifson, Maud Mavigner, Mauricio A. Martins, Ann Chahroudi
Abstract
Ubiquitination is an important post-translational modification associated with essential cellular processes and implicated in regulation of immunity. Here we show that deletion of the E3 ubiquitin ligase Hectd3, germline or in hematopoietic compartment, including in CD11c+ cells, causes a more severe DSS-induced colitis and increased production of proinflammatory cytokines. Hectd3 mRNA levels were found reduced in colonic tissues of patients with ulcerative colitis (UC), which highlights a potential role for Hectd3 in regulating inflammatory responses in UC. We identified Myd88, a central adaptor in the TLR/IL1R signaling and inflammatory response, as a target for Hectd3 ubiquitination. We demonstrate that Hectd3 directly ubiquitinates Myd88 through K27-linked Poly-Ub chains in a nondegradative manner. Hectd3 KO GM-CSF-bone marrow derived cells treated with the TLR4 ligand lipopolysaccharide (LPS) produced more proinflammatory cytokines, show elevated phosphorylation of NF-κB and IRAK4, as well as elevated association of Myd88 with IRAK4, demonstrating that Hectd3 controls Myd88-IRAK4-NF-κB axis. Inhibition of Myd88 activity rescued colitis severity in the Hectd3 KO mice, including the elevated proinflammatory cytokine production. Thus, our results establish Myd88 as a new target for Hectd3 non-degradative polyubiquitination and restriction of immune colonic inflammation.
Authors
Shamima Islam, Shahnewaj Mannan, Ashley Zuniga, Upasana Parthasarathy, Valeriu B. Cismasiu, Leonardo Silvane, Sayan Chakraborty, Divya Priyanka Talada, Raghwendra Pratap Singh, Tomas Zelenka, Amreen Naveen, Sephra Chyanne Vickers, Michael G.M. Grant, Jonathan J. Cho, Theodore Drashansky, Alexander J. Kwiatkowski, Xintong Liu, Ross Tomaino, Olga A. Guryanova, Mariola J. Ferraro, Sang Yong Kim, Christian Jobin, Benjamin G. Keselowsky, Hongmin Li, Paulo C. Rodriguez, Martina Molgora, Amer A. Beg, Timothy I. Shaw, Zheng Ruan, Lixin Wan, Dorina Avram
Abstract
Severe SARS-CoV-2 infection is characterized by lung hyperinflammation, impaired IFN responses, and defective T cell activation, yet the molecular drivers of these immune dysregulations remain incompletely understood. Caspase-11 (CASP11), a key effector of the noncanonical inflammasome, has been shown to mediate an innate hyperinflammatory response and cytokine release in a mild SARS-CoV-2 infection model. However, the role played by CASP11 in severe SARS-CoV-2 disease and how it affects adaptive immunity has not been identified. Here, we found that CASP11 exacerbates severe SARS-CoV-2 pathogenesis by amplifying early innate immune responses while concurrently impairing antiviral CD8+ T cell immunity. Using global KO mice, hematopoietic BM chimeras, and Cx3cr1-expressing mononuclear phagocyte system cell–specific CASP11 deletion models, we show that targeting CASP11 reduces lung inflammation, promotes early NK cell–mediated IFN-γ production, and enhances robust virus-specific effector CD8+ T cell responses. This was associated with enhanced viral clearance and improved survival, even under lethal infection conditions. Importantly, CASP11-KO mice also exhibited faster resolution of postviral inflammation. These findings position CASP11 as a promising immunomodulatory target for acute and delayed manifestations of severe SARS-CoV-2 infection.
Authors
Mostafa M. Eltobgy, Mohamed M. Shamseldin, Owen D. Whitham, Heba M. Amer, Jeffrey R. Atkinson, Asmaa Badr, Jesse M. Hall, Gauruv Gupta, Yara Y. Hassan, Rabab El-Mergawy, Richard Perez, Sarah E. Faber, Maciej Pietrzak, Amy Webb, Xiaoli Zhang, Adam D. Kenney, Destiny Bissell, Jihad I. Omran, Shady Estfanous, Kylene P. Daily, Amir Yousif, Marisa R. Joldrichsen, Andrew McNamara, Mahesh KC, Mark E. Peeples, Emily A. Hemann, Hazem E. Ghoneim, Shahid M. Nimjee, Estelle Cormet-Boyaka, Jianrong Li, Prosper N. Boyaka, Jacob S. Yount, Benjamin M. Segal, Purnima Dubey, Amal O. Amer
Abstract
Mycoplasma pneumoniae pneumonia (MPP) can cause serious extrapulmonary complications, including life-threatening thrombosis. This study aimed to elucidate the roles of neutrophils and neutrophil extracellular traps (NETs) in vascular endothelial cell (EC) activation in pediatric MPP-associated thrombosis. We analyzed the relationship between neutrophils and thrombosis in children with MPP and used mouse models of neutrophilia (Csf3 plasmid injection), neutropenia (Csf3 deficient, Csf3–/–), and defective NETs formation (Pad4 deficient, Pad4–/–). The effects of neutrophils and NETs on EC activation were further examined in vivo, in vitro, and in human samples. Elevated neutrophil count was observed in patients with thrombosis and functioned as a potential diagnostic marker as well as a risk factor for MPP-associated thrombosis. EC activation was enhanced in MPP mice with neutrophilia but attenuated in neutropenic or Pad4–/– mice. NETs activated ECs through TLR2 and JAK/STAT3 signaling, and inhibition of NETs formation (Cl-amidine), TLR2 (C29), and JAK (upadacitinib) each attenuated this response. Strong correlations among neutrophils, NETs, EC activation, and thrombosis were observed in pediatric patients. These findings suggest that neutrophils promoted thrombosis in MPP via NETs-mediated EC activation involving TLR2 and JAK/STAT3 signaling. This study provides mechanistic insights into the inflammatory-thrombotic processes in MPP-associated thrombosis and offers a rationale for further investigation of neutrophils, NETs, TLR2, and JAK/STAT3 signaling in this context.
Authors
Xia Huang, Yifan Zhu, Yun Guo, Tian Lv, Haiyan Gu, Yingying Luo, Dan Li, Hang Sun, Deyu Zhao, Feng Liu
Abstract
Surgical stress, such as liver ischemia/reperfusion (I/R) injury characterized by robust neutrophil infiltration and immune activation, induces sterile inflammation that reshapes tissue immunity and contributes to organ dysfunction, yet the intercellular circuits that spatially orchestrate these responses within the hepatic immune microenvironment remain incompletely defined. Here, we integrate single-cell RNA sequencing, spatial transcriptomics, high-dimensional spectral flow cytometry, and metabolomics to resolve the hepatic immune landscape following I/R at cellular and spatial resolution. While confirming extensive immune remodeling, we identify a dominant neutrophil–Kupffer cell communication axis mediated by neutrophil-derived thrombospondin-1 (TSP-1), which selectively engages CD36 on Kupffer cells. This interaction drives coordinated immune-metabolic reprogramming in Kupffer cells, characterized by suppression of oxidative phosphorylation, enhanced glycolysis, and remodeling of sphingolipid metabolism, including accumulation of hexosylceramides. Spatial analyses reveal preferential neutrophil–Kupffer cell colocalization within necrotic niches, and cross-species integration with human liver transplant datasets demonstrates conserved upregulation of the TSP-1/CD36 axis following reperfusion. Pharmacologic inhibition of TSP-1 attenuates liver injury and inflammatory responses in vivo. Together, these findings define a spatially organized, neutrophil-driven immune-metabolic circuit that governs functional reprogramming of Kupffer cells during surgical stress and identify the TSP-1/CD36 pathway as a conserved and targetable mediator of sterile liver injury.
Authors
Hongji Zhang, Xingping Huang, Preethi Jayakumar, Yunwei Zhang, Ti Yang, Xiaorong Guo, Grace Wu, Amrendra Kumar, Vijaya Bharti, Amblessed Onuma, Chengli Shen, Dequan Lou, Patricia S. Latham, James M. Crawford, Kong Chen, Anna E. Vilgelm, Lopa Mishra, Allan Tsung, Meihong Deng, Hai Huang
Abstract
Type 2 innate lymphoid cells (ILC2) are a population of lineage-negative cells in the lung, gastrointestinal tract, and skin which have emerged as a significant component of type 2 allergic inflammation. The regulation of cyclooxygenase-2 (COX-2) metabolites is critical to the pathophysiology of many inflammatory disorders, including allergic asthma. While COX-2 regulates Th9 and Th17 cell differentiation and function during allergic lung inflammation, it remains unknown whether COX-2 also regulates ILC2 cell differentiation and function under similar conditions. To address this question, we examined lung ILC2 cells from COX-2+/+ and COX-2-/- mice after ovalbumin (OVA)- or Alternaria-induced allergic lung inflammation. ILC2 cells were significantly increased in COX-2-/- lungs compared with COX-2+/+ lungs after OVA exposure in vivo. The increase in ILC2 cells was accompanied by an increase in expression of the cytokines IL-5 and IL-13, and the transcription factor GATA3. Both genetic disruption and selective inhibition of COX-2 significantly increased ILC2 cell differentiation from isolated common lymphoid progenitor cells (CLP) in vitro. Furthermore, COX-2-derived PGE2 acting via EP2 receptors significantly reduced IL-33 and TSLP expression, and attenuated ILC2 cell differentiation in vitro and in vivo. Thus, during allergic lung inflammation, COX-2-derived PGE2 signals through the EP2 receptor to negatively regulate lung ILC2 cell differentiation and function.
Authors
Hong Li, Matthew L. Edin, Daniel Menendez, J. Alyce Bradbury, Joan P. Graves, Artiom Gruzdev, Gregory S. Whitehead, Maria I Sifre, Laura M. DeGraff, Darryl C. Zeldin
Abstract
Sterile tissue injury triggers a rapid neutrophil response that can be either pathogenic or protective, reflecting substantial functional heterogeneity of neutrophils; however, the neutrophil subsets underlying these divergent functions remain poorly defined. Here, using a well-established sterile corneal injury model, we delineate the time-dependent functional and transcriptional heterogeneity of neutrophils following sterile injury. Temporal neutrophil depletion revealed that neutrophils recruited at day 1, but not day 7, are essential for suppressing inflammation, promoting epithelial healing, and preserving nerve density. Single-cell RNA sequencing uncovered substantial transcriptional heterogeneity among circulating neutrophils and their rapid reprogramming within 24 hours after injury. Specifically, Il1r2 was highly enriched in these early injury-responsive neutrophils. Functional validation demonstrated that adoptive transfer of IL-1R2+ neutrophils markedly attenuated inflammation and accelerated epithelial and nerve repair, restoring tissue integrity, whereas IL-1R2- neutrophils exacerbated inflammatory responses. Together, these findings identify IL-1R2+ neutrophils as an early protective neutrophil subset expanded by sterile injury that restrains excessive inflammation and preserves tissue homeostasis, providing mechanistic insight into injury-induced neutrophil reprogramming and highlighting a potential therapeutic target for enhancing tissue repair.
Authors
Hyun Ju Lee, Jung Hwa Ko, Joo Youn Oh
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