Project description:The main project purpose is to investigate the fundamental physiological state of Mycobacterium tuberculosis during the infection and the mycobacterial response within the infected host tissue, human lung. High-throughput proteomic analysis of M. tuberculosis cells will be involved to solve this problem. The description of pattern of proteins expressed in M. tuberculosis cells extracted directly from clinical material of patients with tuberculosis defines the main novelty of the given project. Undoubtedly, the intermediate project results describing the features of M. tuberculosis strains proteome in vitro will also be essential for the global scientific community.
Project description:Tuberculosis and non-tuberculous mycobacterial (NTM) diseases are infections caused by Mycobacterium tuberculosis and non-tuberculous mycobacteria, leading to the formation of granulomatous lesions with caseous necrosis in the lungs. We applied spatial transcriptomics at single-cell resolution (CosMx Spatial Molecular Imaging) to human lung samples from patients with mycobacterial infections. RNA-seq was also performed on the samples.
Project description:Tuberculosis and non-tuberculous mycobacterial (NTM) diseases are infections caused by Mycobacterium tuberculosis and non-tuberculous mycobacteria, leading to the formation of granulomatous lesions with caseous necrosis in the lungs. We applied spatial transcriptomics at single-cell resolution (CosMx Spatial Molecular Imaging) to human lung samples from patients with mycobacterial infections. RNA-seq was also performed on the samples.
Project description:The alarming rise of antimicrobial resistance in Mycobacterium tuberculosis coupled with the shortage of new antibiotics has made tuberculosis (TB) control a global health priority. Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit the growth of multi-drug resistant isolates of M. tuberculosis. Repurposing NSAIDs, with known clinical properties and safety records, offers a direct route to clinical trials. Therefore we investigated the novel mechanisms of anti-mycobacterial action of the NSAID, carprofen. Integrative molecular and microbiological approaches revealed that carprofen, a bactericidal drug, inhibited bacterial drug efflux mechanisms. In addition, carprofen restricted mycobacterial biofilm-like growth, highlighting the requirement of efflux-mediated communicative systems for the formation of biofilms. Transcriptome profiling revealed that carprofen likely acts by inhibiting respiration through the disruption of membrane potential, which may explain why spontaneous drug-resistant mutants could not be raised due to the pleiotropic nature of carprofen’s anti-tubercular action. This immunomodulatory drug has the potential to reverse TB antimicrobial resistance by inhibiting drug efflux pumps and biofilm formation, and paves a new chemotherapeutic path for tackling tuberculosis.
Project description:Human tuberculosis (TB) is caused by various members of the Mycobacterium tuberculosis (Mtb) complex. Differences in host response to infection have been reported, illustrative of a need to test vaccines against multiple Mtb strains in preclinical studies. We have previously shown that the murine lung and spleen mycobacterial growth inhibition assay (MGIA) can be used to assess control of ex vivo mycobacterial growth by host cells. The number of mice required for the assay is lower than in vivo Mtb challenge studies, facilitating testing of multiple strains and/or the incorporation of other cellular analyses which may inform the design of future in vivo studies. Here, we present an optimised mycobacterial growth inhibition assay (MGIA) for testing TB vaccines against multiple Mtb clinical isolates. Using an ancient and modern strain of the Mtb complex, we demonstrate that ex vivo bacillus Calmette–Guérin (BCG)-mediated mycobacterial growth inhibition recapitulates protection observed in the lung and spleen following in vivo infection of mice. Further, cellular and transcriptional correlates of growth inhibition in the lung MGIA were identified. Flow cytometric analysis revealed an increased proportion of dendritic cells and interstitial macrophages in the lung cell input from mice vaccinated parentally with BCG compared with unvaccinated mice. RNA-seq analysis of the lung cell input revealed shared and strain-specific transcriptional correlates of BCG-mediated growth inhibition. The ex vivo MGIA may represent a platform to gain early insight into vaccine performance against a collection of Mtb strains to improve preclinical evaluation of TB vaccines.
Project description:Human tuberculosis (TB) is caused by various members of the Mycobacterium tuberculosis (Mtb) complex. Differences in host response to infection have been reported, illustrative of a need to test vaccines against multiple Mtb strains in preclinical studies. We have previously shown that the murine lung and spleen mycobacterial growth inhibition assay (MGIA) can be used to assess control of ex vivo mycobacterial growth by host cells. The number of mice required for the assay is lower than in vivo Mtb challenge studies, facilitating testing of multiple strains and/or the incorporation of other cellular analyses which may inform the design of future in vivo studies. Here, we present an optimised mycobacterial growth inhibition assay (MGIA) for testing TB vaccines against multiple Mtb clinical isolates. Using an ancient and modern strain of the Mtb complex, we demonstrate that ex vivo bacillus Calmette–Guérin (BCG)-mediated mycobacterial growth inhibition recapitulates protection observed in the lung and spleen following in vivo infection of mice. Further, cellular and transcriptional correlates of growth inhibition in the lung MGIA were identified. Flow cytometric analysis revealed an increased proportion of dendritic cells and interstitial macrophages in the lung cell input from mice vaccinated parentally with BCG compared with unvaccinated mice. RNA-seq analysis of the lung cell input revealed shared and strain-specific transcriptional correlates of BCG-mediated growth inhibition. The ex vivo MGIA may represent a platform to gain early insight into vaccine performance against a collection of Mtb strains to improve preclinical evaluation of TB vaccines.
Project description:The main project purpose is to investigate the fundamental physiological state of M. tuberculosis (MTB) during the infection and the mycobacterial response within the infected host tissue, human lung. High-throughput proteomic analysis of MTB cells will be involved to solve this problem. The description of pattern of proteins expressed in MTB cells extracted directly from clinical material of patients with tuberculosis defines the main novelty of the given project. Undoubtedly, the intermediate project results describing the features of MTB strains proteome in vitro will also be essential for the global scientific community.
Project description:We present an infection study with pathogenic and non-pathogenic mycobacterial strains that have vastly different characteristics. The early/late host response to infection with these detergent-free cultured strains will be analysed through Ampliseq and further validated through qPCR in an attempt to provide information on the subtleties which may ultimately contribute to the virulent phenotype. Proceeding to the next objective of the study is to knock-down (siRNA)/knock-up (saRNA) selected differentially expressed mRNA to study their role in the intracellular survival of M. tuberculosis
Project description:Mycobacterium tuberculosis is the causative agent of tuberculosis, a disease that affects one-third of the world’s population. The sole extant vaccine for tuberculosis is the live attenuated Mycobacterium bovis bacille Calmette-Guerin (BCG). We examined 13 representative BCG strains from around the world to ascertain their ability to express DosR-regulated dormancy antigens. These are known to be recognized by T-cells of M. tuberculosis infected individuals, especially those harboring latent infections. Differences in expression of these antigens could be valuable for use as diagnostic markers to distinguish BCG vaccination from latent tuberculosis. We determined that all BCG strains were defective for induction of two dormancy genes, narK2 (Rv1737c) and narX (Rv1736c). NarK2 is known to be necessary for nitrate respiration during anaerobic dormancy. Analysis of the narK2/X promoter region revealed a base substitution mutation in all tested BCG strains and M. bovis in comparison to the M. tuberculosis sequence. We also show that nitrate reduction by BCG strains during dormancy was greatly reduced compared to M. tuberculosis and varied between tested strains. Several dormancy regulon transcriptional differences were also identified among the strains, as well as variation in their growth and survival. These findings demonstrate defects in DosR regulon expression during dormancy and phenotypic variation between commonly used BCG vaccine strains. Keywords: Comparison of induction of a subset of genes between various mycobacterial strains.
Project description:Members of the Mycobacterium (M.) abscessus complex (MABC) are rapidly growing mycobacteria showing smooth and/or rough colony morphotype. While not as virulent as M. tuberculosis, they can cause soft tissue infection and fatal pulmonary disease, especially in patients with cystic fibrosis. Diagnosing MABC pulmonary disease is challenging since the isolation of M. abscessus from respiratory samples is in itself not diagnostic and the clinical features are often non-specific. Immunologic assays, which could aid in the understanding and diagnosis of the disease, are not available. In this study eight rough and six smooth colony morphotype isolates were collected from seven clinical MABC strains and the M. abscessus reference strain ATCC19977, as six strains showed both morphotypes simultaneously and two strains only showed a rough morphotype. Clinical isolates were submitted to whole genome sequencing. Quantitative proteomic analysis was performed on bacterial lysates and the culture supernatant of all 14 isolates. Supernatant proteins present in all isolates were compared in a BLAST search against other clinically significant mycobacterial species to determine species-specific proteins of MABC. In silico B- and T-cell epitope prediction was performed for species-specific proteins. All clinical strains were found to be M. abscessus ssp. abscessus. Six of seven rough colony clinical isolates contained genetic changes in the MAB_4099c gene, which is a likely genetic basis for the rough morphotype. Proteomic analysis detected 3 137 different proteins in total of which 79 proteins were found in the culture supernatants of all isolates. BLAST analyses of these 79 proteins identified 12 of those exclusively encoded by all members of MABC plus M. immunogenum. In silico prediction of epitopes predicted B- and T-cell epitopes in all these 12 species-specific proteins, rendering them promising candidates for future studies on immune pathogenesis and immune diagnostic tools for MABC disease.