Infectious disease
Abstract
Mycobacteriumtuberculosis (Mtb), the causative agent of tuberculosis (TB), is the most common coinfection in people living with HIV-1 (PLWH). This coinfection is associated with accelerated HIV-1 disease progression and reduced survival. However, the immunological and virological mechanisms driving this progression are not completely understood. To address this knowledge gap, using pleural effusion samples from PLWH and TB, we investigated how the HIV-1 genetic landscape and the anti-HIV-1 immune response are impacted by a TB-associated microenvironment. Our results revealed an enrichment of genetically intact HIV-1 and impaired CD8+ T cell-mediated antiviral response at this site of HIV-1/Mtb coinfection. Moreover, efficient CD8+ T cell activation was inhibited by lipids present in the TB-associated pleural effusion. These findings indicate that this immune microenvironment induced by TB promotes the persistence of cells infected with replication-competent HIV-1 by creating a niche of reduced antiviral immune pressure, potentially contributing to the worsened clinical outcomes observed in PLWH and TB.
Authors
Samantha Cronin, Jennifer Simpson, Andrea Pereyra-Casanova, Yuchen Li, Josefina Marín-Rojas, Freja A. Warner van Dijk, Katie Fisher, Daniel J. Buffa, Hafsa Rana, Zoï Vahlas, Joaquina Barros, Mariano Maio, Thomas R. O'Neil, Kirstie M. Bertram, Eunok Lee, Najla Nasr, Andrew N. Harman, Gabriela Turk, Maria Florencia Quiroga, Anthony D. Kelleher, Christel Vérollet, Luciana Balboa, Sarah Palmer, Gabriel Duette
Abstract
Plasmodium falciparum sporozoite (PfSPZ) vaccines, comprised of aseptic, purified, live parasites that arrest during or just after liver stage development, show excellent safety and efficacy in humans. They can induce complete protection against Pf infection, mediated primarily by cellular immune responses against parasite antigens expressed in hepatocytes. Current PfSPZ vaccines rely on the West African PfNF54 parasite, which uniquely produces high numbers of PfSPZ in mosquitoes, facilitating manufacturing efficiency. However, PfNF54 has relatively low hepatocyte infectivity, limiting potency. We created hybrid pan-African Pf strains by genetically crossing PfNF54 with East African Pf strains. The hybrid, AV27, was selected for development based on balanced contribution of parental genomes, high PfSPZ production and high liver stage infectivity. As compared to NF54-based PfSPZ vaccines, we expect AV27-based vaccines will have greater and broader efficacy at lower doses due to higher liver stage infectivity and inclusion of unique East African CD8+ T cell epitopes.
Authors
Lucia Pazzagli, Bethany Jenkins, Ankit Dwivedi, Asha Patil, Yonas Abebe, Tales V. Pascini, Urvashi Rai, Priya Gupta, Nastaran Rezakhani, Chakshu Gandhi, Yiwei Yang, Sudhir Kumar, Mohd Kamil, Gigliola Zanghí, Manuel Llinás, Stephen L. Hoffman, Joana C. Silva, Ashley M. Vaughan, B. Kim Lee Sim
Abstract
CFTR in the lung epithelium contributes to the secretion of a surface liquid layer that is essential to lung homeostasis and defense. The understanding of how liquid is secreted in the lung is derived largely from studies of the airway epithelium. Comparatively little is known about liquid secretion mechanisms in the alveolar epithelium, including its cellular source. To define which cell type drives alveolar liquid secretion, we generated transgenic mice that expressed a Cftr null allele in alveolar type 1 (AT1) cells, type 2 (AT2) cells, or both, then viewed liquid secretion in live alveoli using confocal microscopy of isolated, perfused lungs. Our findings show liquid secretion was blocked in alveoli of all three transgenic mice, indicating that both AT1 and AT2 cells contribute to alveolar liquid secretion. Cftr null expression in AT1 cells also blocked the secretion-mediated clearance of small particle and bacterial clusters from alveolar walls, indicating that AT1 cell CFTR contributes to alveolar defense. Together, these findings show alveolar liquid secretion depends on both AT1 and AT2 cell CFTR, and that CFTR in AT1 cells – a cell type not traditionally considered in liquid secretion mechanisms or CFTR-related lung diseases – contributes to lung liquid dynamics and host defense.
Authors
Sayahi Suthakaran, Sonya Homami, Deebly Chavez, Stephanie Tang, Sarah K.L. Moore, Chaya Sussman, Jimmy Zhang, Clemente J. Britto, Alice Prince, Alison J. May, Jaymin J. Kathiriya, Jaime L. Hook
Abstract
Authors
Ian A. Mellis, Madeline Wu, Kristin Daniel, Hsiang Hong, Yicheng Guo, David D. Ho
Abstract
Neonatal sepsis is a predominant cause of neonatal mortality and long-term morbidity which severely effects preterm and low birth weight newborns. Antibiotic resistance and long-term developmental issues associated with neonatal sepsis necessitates finding new and improved treatment options. Interleukin-27 (IL-27) has diverse influences on the immune response, is elevated during the neonatal period compared to adulthood, and continues to rise further during infection. Elevated levels of IL-27 early in life predispose the host to impaired control of the pathogen burden and increased mortality. This study explored the therapeutic potential of IL-27p28 antibody administration to improve treatment outcomes during murine neonatal sepsis. Sepsis was induced by subcutaneous inoculation of K1-encapsulated Escherichia coli and the neonatal pups were rescued with IL-27p28 monoclonal antibody. Pups that received prophylactic antibody prior to the infection demonstrated superior bacterial clearance and significant weight gain compared to controls during infection. The combination of subclinical dose of gentamicin and IL-27p28 antibody administered 2h post-infection, significantly improved bacterial clearance, glucose homeostasis, with reduced serum levels of IL-6 and TNF-α, vital organ damage and significantly improved the survival rate of infected pups compared to gentamicin alone. These findings suggest that IL-27p28 antagonization represents a promising therapeutic tool for treatment of neonatal sepsis.
Authors
Madhavi Annamanedi, Jessica M. Povroznik, Samantha Arevalo-Marcano, Cory M. Robinson
Abstract
Single-cell RNA sequencing (scRNA-seq) of peripheral blood mononuclear cells (PBMCs) has enhanced our understanding of host immune mechanisms in small cohorts, particularly in diseases with complex and heterogeneous immune responses such as sepsis. However, standard PBMC isolation from blood requires technical expertise and over two hours of onsite processing using Ficoll density gradient separation (‘Ficoll’) for scRNA-seq compatibility, precluding large-scale sample collection at most clinical sites. To minimize onsite processing, we developed Cryo-PRO (Cryopreservation with PBMC Recovery Offsite), a method of immediate onsite whole blood cryopreservation and subsequent batched PBMC isolation in a central laboratory prior to sequencing. We compared multimodal single-cell immune profiling results from samples processed using Cryo-PRO versus standard onsite Ficoll separation in 23 patients with sepsis. Critical outputs including cell substate fractions, marker genes, and surface protein expression were similar for each method across multiple cell types and substates, including an important monocyte substate enriched in patients with sepsis. Capture of T cell receptor transcripts was also comparable across both methods. Cryo-PRO reduced onsite sample processing time from >2 hours to <15 minutes and was reproducible across two enrollment sites, thus demonstrating potential for expanding multimodal single-cell analyses in multicenter studies of sepsis and other diseases.
Authors
Alyssa K. DuBois, Pierre O. Ankomah, Alexis C. Campbell, Renee Hua, Olivia K. Nelson, Christopher A. Zeuthen, M. Kartik Das, Shira Mann, Abigail Mauermann, Blair A. Parry, Nathan I. Shapiro, Michael R. Filbin, Roby P. Bhattacharyya
Abstract
The estrogen receptor is hypothesized to directly influence HIV-transcription and latency but is also critical for immune signaling. However, the mechanisms of action of the estrogen receptor (ER) in immune cells in the context of HIV are limited, and relevant to HIV cure strategies, the influence of latency reversal agents (LRAs) on the ER pathway are unknown. We evaluated a) the impact of estrogen (E2) on the nuclear translocation of estrogen receptor α (ERα) in CD4+ T cells, b) the ability of Fulvestrant, a selective estrogen receptor degrader (SERD), and ARV-471, a novel, potent, PROteolysis TArgeting Chimera (PROTAC) selective ERα degrader to modulate ER and c) the impact of different classes of LRAs on ER signaling. In contrast to what has been demonstrated in oncology, E2 does not induce ERα nuclear translocation in CD4+ T cells. Similarly, neither Fulvestrant nor ARV-471 induced degradation of ERα in CD4+ T cells. LRAs significantly downregulated ERα gene and protein expression in both PBMCs and CD4+ T cells. Collectively, our results suggest that estrogen influences on HIV transcription are not likely a consequence of canonical nuclear ERα mechanisms. The consequences of LRA downregulation of ER, a protein important for immune signaling, warrants further investigation.
Authors
Cristina Ceriani, Priya Khetan, Anthony Abeyta-Lopez, Kena J. Lemu, Prachi Meher, Brigitte Allard, Katherine S. James, Anne-Marie W. Turner, David M. Margolis, Nancie M. Archin
Abstract
BACKGROUND There are no known serum biomarkers that provide mechanistic insight or prognostic enrichment for post–COVID-19 pulmonary fibrosis.METHODS We tested associations of serum biomarkers with radiographic fibrosis-like abnormalities (reticulation, traction bronchiectasis, or honeycombing) on thoracic computed tomography (CT) scans 4 months, 15 months, and 3 years after hospitalization in an American discovery cohort of severe-to-critical COVID-19 survivors, and externally validated findings in 2 Canadian cohorts of moderate-to-critical COVID-19 survivors. In the discovery cohort, we investigated the dose-response relationship of the biomarker with CT-derived airway-to-lung ratio. We performed single-cell RNA sequencing (scRNA-seq) of transbronchial lung biopsies from COVID-19 survivors obtained 3 years after COVID-19 hospitalization and conducted immunofluorescence analysis of COVID-19 lung explants.RESULTS Among 150 discovery cohort participants, only higher levels of circulating club cell secretory protein-16 (CC16, encoded by the SCGB1A1 gene) at hospital discharge, 4 months, 15 months, and 3 years were associated with thoracic CT fibrosis-like abnormalities in cross-sectional and longitudinal analyses. Higher CC16 levels were associated with thoracic CT fibrosis-like abnormalities in 2 validation cohorts (n = 56 and n = 37). CC16 levels were linearly associated with increased airway-to-lung ratio. scRNA-seq revealed increased proportions of epithelial cells expressing SCGB1A1 and SCGB1A1/MUC5B in COVID-19 survivors with fibrosis. Immunofluorescence analysis of COVID-19 lung explants demonstrated increased numbers of SCGB1A1-expressing epithelial cells only in small (<100 μm) airways, with 3-fold more CC16/MUC5B-coexpressing cells in respiratory bronchioles..CONCLUSION. Higher CC16 levels are associated with CT fibrosis-like abnormalities for up to 3 years following moderate-to-critical COVID-19. Increased CC16 reflects dysregulated small airway epithelial progenitor cell remodeling and increased expansion of CC16+MUC5B+ epithelial cells in respiratory bronchioles after COVID-19.TRIAL REGISTRATION Not applicable.FUNDING Department of Defense, NIH, and Japan Society for the Promotion of Science for Young Scientists.
Authors
Matthew R. Baldwin, Ansley E. Jones, David Zhang, Chandan Gurung, Zain Khan, Anjali Saqi, Xuehan Yang, Ying Wei, Renu Nandakumar, Scarlett O. Murphy, Claire F. McGroder, Faisal Shaikh, Selim Arcasoy, Luke Benvenuto, Harpreet Grewal, Benjamin M. Smith, Eric A. Hoffman, Agnes C.Y. Yuen, Parteek Johal, Christopher Carlsten, Christopher J. Ryerson, J. Brent Richards, Alyson W. Wong, Tomoko Nakanishi, Aditi S. Shah, Christine Kim Garcia
Abstract
Influenza A virus (IAV) infection is a major cause of morbidity and mortality for patients worldwide. Alveolar type 2 (AT2) cells are the preferential target of IAV as part of the pathogenesis of viral pneumonia and acute respiratory distress syndrome (ARDS). Early IAV infection of alveolar cells has been challenging to model both in vitro and in vivo. To address this challenge, we used a combination of murine and human primary alveolar organoids to define methods for robust IAV infection and evaluated cell-autonomous consequences of IAV using a temporal series of multiome paired single nuclei RNA and ATAC sequencing assays. Infected AT2 cells demonstrated conserved changes defined by early loss of surfactant secretion, decreased lipid biogenesis, a rapid burst of antiviral response, and late viral-mediated suppression. Surprisingly, uninfected AT2 cells underwent substantial transcriptional and epigenomic changes in IAV-treated cultures, leading to transition to damage-associated cell states within hours via a process driven by the inflammatory milieu of murine organoids. Together, these data provide new methods for high-fidelity modeling of IAV infection in alveolar cells and defined a conserved AT2 cell response signature to IAV with implications for ARDS pathogenesis.
Authors
Amber Elitz, Sharlene Fernandes, Kathleen C.S. Cook, Helen I Warheit-Niemi, Barbara Zhao, Andrea Toth, Amanda L. Zacharias, William J. Zacharias
Abstract
Vaccine development for tuberculosis is a global priority. Our studies using Collaborative Cross (CC) mice show that genetic diversity influences the efficacy of BCG, the most widely used TB vaccine. BCG vaccination of CC042 mice reduced their lung bacillary burden and increased their survival following low-dose aerosol Mycobacterium tuberculosis infection (MTBI), despite impaired T cell trafficking due to a defective Itgal gene. BCG vaccination conferred early bacillary control which appeared to be independent of B cell or T cell recall responses following MTBI. In contrast, long term survival of BCG-vaccinated CC042 mice after MTBI required T cells. Thus, CC042 mice reveal two phases of immunity induced by BCG: an early phase mediated by innate immunity or innate-like T cells and a later phase mediated by conventional memory CD4 and/or CD8 T cells. Although measurement of vaccine-induced protection 30 days after MTBI is a standard measure of vaccine efficacy in the TB model, this time point might be independent of memory T cells in CC042 mice. Our results suggest that vaccine-elicited innate/innate-like responses could have a larger role in protection than previously considered. The concordance between lung CFU, pathology, and survival make CC042 mice useful for mechanistic studies on vaccine-induced immunity.
Authors
Abiola F. Ogunsola, Rocky Lai, Kelly Cavallo, Anthony V. Tran, Gillian L. Beamer, Samuel M. Behar
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