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.
View Article and Find Full Text PDFTuberculosis (TB) remains the leading cause of death due to infection globally. Bacillus Calmette Guérin (BCG), a live attenuated bacterial strain, is the only available TB vaccine, but it has poor efficacy in preventing pulmonary TB in adults. There are advantages associated with the BCG platform however, including a remarkable safely profile, billions of administered doses and a public health ecosystem associated with its production, administration and care.
View Article and Find Full Text PDFMicrobiol Spectr
September 2025
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.
View Article and Find Full Text PDFThe 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.
View Article and Find Full Text PDFHum Vaccin Immunother
December 2024
, the causative agent of amebiasis, is one of the top three parasitic causes of mortality worldwide. However, no vaccine exists against amebiasis. Using a lead candidate vaccine containing the LecA fragment of Gal-lectin and GLA-3M-052 liposome adjuvant, we immunized rhesus macaques via intranasal or intramuscular routes.
View Article and Find Full Text PDFWith devastating health and socioeconomic impact worldwide, much work is left to understand the Coronavirus Disease 2019 (COVID-19), with emphasis in the severely affected elderly population. Here, we present a proteomics study of lung tissue obtained from aged vs. young rhesus macaques (Macaca mulatta) and olive baboons (Papio Anubis) infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
View Article and Find Full Text PDFThe aim of this study was to determine the effect of non-surgical periodontal therapy (NSPT) on mRNA expression of metallothionein (MT) and its levels in serum, saliva and gingival crevicular fluid (GCF) of smokers (S) and non-smokers (NS) with periodontitis (P).A total of 100 participants were included: 48 periodontally healthy (PH) subjects (24 S [PH + S] and 24 NS [PH + NS]) and 52 patients with P (27 S [P + S] and 25 NS [P + NS]). Clinical parameters were recorded, and biofluids (serum, saliva and GCF) and gingival tissue samples were obtained at baseline in all groups and 3 months after NSPT in P groups.
View Article and Find Full Text PDFJ Anaesthesiol Clin Pharmacol
December 2023
HIV and TB are the cause of significant worldwide mortality and pose a grave danger to the global public health. TB is the leading cause of death in HIV-infected persons, with one in four deaths attributable to TB. While the majority of healthy individuals infected with (Mtb) are able to control the infection, co-infection with HIV increases the risk of TB infection progressing to TB disease by over 20-fold.
View Article and Find Full Text PDFMycobacterium tuberculosis, the causative agent of tuberculosis, is acquiring drug resistance at a faster rate than the discovery of new antibiotics. Therefore, alternate therapies that can limit the drug resistance and disease recurrence are urgently needed. Emerging evidence indicates that combined treatment with antibiotics and an immunomodulator provides superior treatment efficacy.
View Article and Find Full Text PDFTuberculosis (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.
View Article and Find Full Text PDFThe expression of indoleamine 2,3-dioxygenase (IDO), a robust immunosuppressant, is significantly induced in macaque tuberculosis (TB) granulomas, where it is expressed on IFN-responsive macrophages and myeloid-derived suppressor cells. IDO expression is also highly induced in human TB granulomas, and products of its activity are detected in patients with TB. In vivo blockade of IDO activity resulted in the reorganization of the granuloma with substantially greater T cells being recruited to the core of the lesions.
View Article and Find Full Text PDF() has developed specialized mechanisms to parasitize its host cell, the macrophage. These mechanisms allow it to overcome killing by oxidative burst and persist in the wake of an inflammatory response. infection in the majority of those exposed is controlled in an asymptomatic form referred to as latent tuberculosis infection (LTBI).
View Article and Find Full Text PDFSensitive and specific blood-based assays for the detection of pulmonary and extrapulmonary tuberculosis would reduce mortality associated with missed diagnoses, particularly in children. Here we report a nanoparticle-enhanced immunoassay read by dark-field microscopy that detects two Mycobacterium tuberculosis virulence factors (the glycolipid lipoarabinomannan and its carrier protein) on the surface of circulating extracellular vesicles. In a cohort study of 147 hospitalized and severely immunosuppressed children living with HIV, the assay detected 58 of the 78 (74%) cases of paediatric tuberculosis, 48 of the 66 (73%) cases that were missed by microbiological assays, and 8 out of 10 (80%) cases undiagnosed during the study.
View Article and Find Full Text PDFA once-weekly oral dose of isoniazid and rifapentine for 3 months (3HP) is recommended by the CDC for treatment of latent tuberculosis infection (LTBI). The aim of this study is to assess 3HP-mediated clearance of M. tuberculosis bacteria in macaques with asymptomatic LTBI.
View Article and Find Full Text PDFDespite a century of research into tuberculosis (TB), there is a dearth of reproducible, easily quantifiable, biomarkers that can predict disease onset and differentiate between host disease states. Due to the challenges associated with human sampling, nonhuman primates (NHPs) are utilized for recapitulating the closest possible modelling of human TB. To establish a predictive peripheral biomarker profile based on a larger cohort of rhesus macaques (RM), we analyzed results pertaining to peripheral blood serum chemistry and cell counts from RMs that were experimentally exposed to in our prior studies and characterized as having either developed active TB (ATB) disease or latent TB infection (LTBI).
View Article and Find Full Text PDFWith the advent of the novel SARS-CoV-2, the entire world has been thrown into chaos with severe disruptions from a normal life. While the entire world was going chaotic, the researchers throughout the world were struggling to contribute to the best of their capabilities to advance the understanding of this new pandemic and fast track the development of novel therapeutics and vaccines. While various animal models have helped a lot to understand the basic physiology, nonhman primates have been promising and much more successful in modelling human diseases compared to other available clinical models.
View Article and Find Full Text PDFAm J Respir Crit Care Med
July 2022
Different () strains exhibit variable degrees of virulence in humans and animal models. Differing stress response strategies used by different strains of could influence virulence. We compared the virulence of two strains of with use in animal model research: CDC1551 and Erdman.
View Article and Find Full Text PDFCirculating pathogen-derived proteins can serve as useful biomarkers for infections but may be detected with poor sensitivity and specificity by standard immunoassays due to masking effects and cross-reactivity. Mass spectrometry (MS)-read immunoassays for biomarker-derived peptides can resolve these issues, but lack standard workflows to select species-specific peptides with strong MS signal that are suitable for antibody generation. Using a () protein as an example, candidate peptides were selected by length, species-specificity, MS intensity, and antigenicity score.
View Article and Find Full Text PDFEmergence of mutant SARS-CoV-2 strains associated with an increased risk of COVID-19-related death necessitates better understanding of the early viral dynamics, host responses and immunopathology. Single cell RNAseq (scRNAseq) allows for the study of individual cells, uncovering heterogeneous and variable responses to environment, infection and inflammation. While studies have reported immune profiling using scRNAseq in terminal human COVID-19 patients, performing longitudinal immune cell dynamics in humans is challenging.
View Article and Find Full Text PDFMar Pollut Bull
January 2022
The dynamics of the coastal aquifers are well-expressed by geochemical and isotopic signatures. Coastal regions often exhibit complex groundwater recharge pattern due to the influence of depression in the Bay of Bengal, tidal variations on surface waters, saline water intrusion and agricultural return flows. In this research, groundwater recharge processes occurring in coastal Tamil Nadu, South India were evaluated using major ion chemistry and environmental isotopes.
View Article and Find Full Text PDFFront Cell Infect Microbiol
January 2022
Coronavirus disease 2019 (COVID-19) is a highly contagious, infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which emerged in late 2019 in Wuhan China. A year after the World Health Organization declared COVID-19 a global pandemic, over 215 million confirmed cases and approximately 5 million deaths have been reported worldwide. In this multidisciplinary review, we summarize important insights for COVID-19, ranging from its origin, pathology, epidemiology, to clinical manifestations and treatment.
View Article and Find Full Text PDFEcotoxicol Environ Saf
January 2022
The present research reports the level of nitrate (NO), associated health risks and possible sources of contamination in groundwater from south India. Many samples (32%) are above or approaching the recommended level of NO for safe drinking water. The correlation analysis indicates different sources of NO contamination in different regions rather than a common origin.
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