Publications by authors named "Shabaana A Khader"

To radically diminish TB incidence and mortality by 2035, as set out by the WHO End TB Strategy, there is a desperate need for improved TB therapies and a more effective vaccine against the deadly pathogen Mycobacterium tuberculosis (Mtb). Aerosol vaccination with the MtbΔsigH mutant protects two different species of NHPs against lethal TB challenge by invoking vastly superior T and B cell responses in the lungs through superior antigen-presentation and interferon-conditioning. Since the Geneva consensus on essential steps towards the development of live mycobacterial vaccines recommends that live TB vaccines must incorporate at least two independent gene knock outs, we have now generated several rationally designed, double (DKO)- and triple (TKO) knock-out mutants in Mtb, each containing the ΔsigH deletion.

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Infections with non-tuberculous mycobacterium (NTM) are on the rise. Here, we investigated an uncommon NTM infection, by M. haemophilum (Mh, n = 3), from a shared geographic location in the USA.

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Unlabelled: The COVID-19 pandemic, triggered by the SARS-CoV-2 virus, has led to global consequences since its emergence in late 2019, impacting health, economies, and societies worldwide. Understanding the early responses following infection will provide crucial insights into the immune mechanisms governing disease progression and protection. We employed the single-cell RNA-sequencing approach using bronchoalveolar lavage cells of rhesus macaques at 0-3 days post-infection (dpi) in a non-human primate model of SARS-CoV-2.

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The need for novel vaccination strategies to control tuberculosis (TB) is underscored by the limited and variable efficacy of the currently licensed vaccine, Bacille Calmette-Guerin (BCG). SigH is critical for Mycobacterium tuberculosis (Mtb) to mitigate oxidative stress, and in its absence Mtb is unable to scavenge host oxidative/nitrosative bursts. The MtbΔsigH (ΔsigH) isogenic mutant induces signatures of the innate immunity in macrophages and protects rhesus macaques from a lethal Mtb challenge.

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Disease tolerance is an evolutionarily conserved host defense strategy that preserves tissue integrity and physiology without affecting pathogen load. Unlike host resistance, the mechanisms underlying disease tolerance remain poorly understood. In the present study, we investigated whether an adjuvant (β-glucan) can reprogram innate immunity to provide protection against influenza A virus (IAV) infection.

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Tuberculosis (TB), caused by the bacterium (), infects approximately one-fourth of the world's population. While most infected individuals are asymptomatic, latent TB infection (LTBI) can progress to cause pulmonary TB (PTB). We recently reported an increased accumulation of mast cells (MCs) in lungs of macaques with PTB, compared with LTBI in macaques.

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Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is one of the top infectious killers in the world. The only licensed vaccine against TB, Bacille Calmette-Guérin (BCG), provides variable protection against pulmonary TB, especially in adults. Hence, novel TB vaccine approaches are urgently needed.

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Calprotectin, a metal ion-binding protein complex, plays a crucial role in the innate immune system and has gained prominence as a biomarker for various intestinal and systemic inflammatory and infectious diseases, including inflammatory bowel disease (IBD) and tuberculosis (TB). Current clinical testing methods rely on enzyme-linked immunosorbent assays (ELISAs), limiting accessibility and convenience. In this study, we introduce the Fab-Enabled Split-luciferase Calprotectin Assay (FESCA), a novel quantitative method for calprotectin measurement.

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Interleukin-1 (IL-1) signaling is essential for controlling virulent Mycobacterium tuberculosis (Mtb) infection since antagonism of this pathway leads to exacerbated pathology and increased susceptibility. In contrast, the triggering of type I interferon (IFN) signaling is associated with the progression of tuberculosis (TB) disease and linked with negative regulation of IL-1 signaling. However, mice lacking IL-1 signaling can control Mtb infection if infected with an Mtb strain carrying the rifampin-resistance conferring mutation H445Y in its RNA polymerase β subunit (rpoB-H445Y Mtb).

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Tuberculosis (TB) caused by () infects up to a quarter of the world's population. Although immune responses can control infection, 5%-10% of infected individuals can progress to active TB disease (progressors). A myriad of host factors regulate disease progression in TB and a better understanding of immune correlates of protection and disease is pivotal for the development of new therapeutics.

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Unlabelled: Tuberculosis is the leading cause of death due to an infectious disease worldwide. Innate lymphoid type 3 cells (ILC3s) mediate early protection during () infection. However, the early signaling mechanisms that govern ILC3 activation or recruitment within the lung during infection are unclear.

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Article Synopsis
  • Early innate immune responses are crucial in determining how the body responds to Mycobacterium tuberculosis (Mtb) infections.
  • Research using conditional knockout mice showed that disabling NF-κB signaling in all myeloid cells made them more susceptible to Mtb, while selectively disabling it in CD11c+ myeloid cells led to stronger immune responses.
  • The findings highlight that NF-κB signaling has different roles depending on the type of myeloid cell, providing early resistance in CD11c-expressing cells and contributing to protection later in LysM-expressing cells during Mtb infection.
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Tuberculosis (TB), caused by the intracellular pathogen (), affects the lungs of infected individuals (pulmonary TB) but can also affect other sites (extrapulmonary TB). The only licensed vaccine bacillus (BCG) protects infants and young children but exhibits variable efficacy in protecting against adult pulmonary TB. Poor compliance and prolonged treatment regimens associated with the use of chemotherapy has contributed to the development of multidrug-resistant (MDR) and extensively drug-resistant (XDR) .

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The alarmin calprotectin (S100A8/A9) is thought to drive a cytokine storm, a hallmark of severe COVID-19. Recent studies report circulating S100A8/A9 levels can distinguish COVID-19 severity but have only been conducted in non-U.S.

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Hematopoietic stem and progenitor cells (HSPCs) play a vital role in the host response to infection through the rapid and robust production of mature immune cells. These HSPC responses can be influenced, directly and indirectly, by pathogens as well. Infection with () can drive lymphopoiesis through modulation of type I interferon (IFN) signaling.

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This study highlights the impact of specific rifampicin-resistance-conferring mutations on the host immune response to (), the causative agent of tuberculosis (TB). Clinical reports have previously suggested that multi-drug-resistant) TB patients exhibit altered peripheral immune responses as compared with their drug-sensitive TB counterparts. The murine model of infection with strains carrying drug-resistance-conferring mutations recapitulated these findings and allowed us to mechanistically interrogate the pathways responsible for driving the divergent immune responses.

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Processing and analyzing single-cell RNA-seq (scRNA-seq) from lung cells are challenging due to the complexity of cell subtypes and biological variations within sample groups. Here, we present a protocol for performing an in-depth assessment on lung lymphocyte populations derived from healthy and Mycobacterium tuberculosis-infected mice. We describe steps for downloading processed scRNA-seq data, integrating samples across different conditions, and performing cluster analysis.

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Tuberculosis (TB) is the leading cause of death due to an infectious agent, with more than 1.5 million deaths attributed to TB annually worldwide. The global dissemination of drug resistance across Mycobacterium tuberculosis (Mtb) strains, causative of TB, resulted in an estimated 450 000 cases of drug-resistant (DR) TB in 2021.

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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.

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Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is a global cause of death. Granuloma-associated lymphoid tissue (GrALT) correlates with protection during TB, but the mechanisms of protection are not understood. During TB, the transcription factor IRF4 in T cells but not B cells is required for the generation of the T1 and T17 subsets of helper T cells and follicular helper T (T)-like cellular responses.

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Introduction: Recent reviews summarize evidence that some vaccines have heterologous or non-specific effects (NSE), potentially offering protection against multiple pathogens. Numerous economic evaluations examine vaccines' pathogen-specific effects, but less than a handful focus on NSE. This paper addresses that gap by reporting economic evaluations of the NSE of oral polio vaccine (OPV) against under-five mortality and COVID-19.

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Tuberculosis (TB) caused by the pathogenic bacterium () is one of the most lethal infectious diseases in the world. Presently, Bacillus Calmette-Guerin, the vaccine approved for use against TB, does not offer complete protection against the disease, which necessitates the development of new therapeutics to treat this infection. Overexpression of transforming growth factor beta (TGF-β) is associated with pulmonary profibrotic changes.

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The mammalian airways and lungs are exposed to a myriad of inhaled particulate matter, allergens, and pathogens. The immune system plays an essential role in protecting the host from respiratory pathogens, but a dysregulated immune response during respiratory infection can impair pathogen clearance and lead to immunopathology. Furthermore, inappropriate immunity to inhaled antigens can lead to pulmonary diseases.

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Severity of pulmonary viral infections, including influenza A virus (IAV), is linked to excessive immunopathology, which impairs lung function. Thus, the same immune responses that limit viral replication can concomitantly cause lung damage that must be countered by largely uncharacterized disease tolerance mechanisms. Here, we show that mitochondrial cyclophilin D (CypD) protects against IAV via disease tolerance.

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