Project description:Rifampicin plays an important role during tuberculosis treatment, which historically contributed for shortening therapy; however, rifampicin resistance has been the intersection for the definition of multi (MDR-TB) and extensively (XDR-TB) resistant outcomes. A key aspect which has contributed for investigations of drug action/resistance is the understanding of the dynamic genome expression, as that analyzed by Proteomics. Proteins from the reference strain, Mycobacterium tuberculosis H37Rv were extracted after 12, 24 and 48 hours over rifampicin challenge at the minimal inhibitory concentration (0.03 μg•mL-1) and identified by LC-MS.
Project description:Extensively drug resistant tuberculosis (XDR-TB) showed many different characteristics including the extreme drug resistance versus the drug sensitive clinical isolates (DS-TB), to know better about the reasons we used the tuberculosis host cells named as THP-1 (one kind of the macrophage cells) to be infected by the XDR-TB and DS-TB.DS strain A36 and the XDR strain B42 and was typical and selected by our lab. Then the total RNA of infected or uninfected THP-1 cells was extract and purified for the analysis by the chip (22K Human Genome chip representing the 21522 ORF of human with the oligonucleotide probe of 70 mer from CapitalBio Corp., Beijing, China). The results reflected the different expressed genes involved in apoptosis, secreted cytokines and signal pathway and so on. Those results might indicate the how the XDR-TB cause the pathogenesis.
Project description:Blood transcriptional signatures may discriminate individuals with tuberculosis (TB) from disease-free controls, or from patients with other infectious or respiratory diseases. To systematically evaluate the diagnostic accuracy of published transcriptional signatures in a clinically relevant population with high burden of TB and human immunodeficiency virus (HIV), adults presenting for investigation of possible pulmonary TB were consecutively recruited at a TB clinic in South Africa. At enrolment, peripheral blood was collected in Tempus tubes (for RNA sequencing) and patients provided two sputum samples (for Xpert and liquid culture). Amongst 181 patients (median age 35 years), 44 (24%) were infected with human immunodeficiency virus (HIV). 54 patients (30%) were diagnosed with Xpert- or culture-positive TB. No alternate diagnoses were available for Xpert- and culture-negative non-TB patients.
Project description:Despite more than a century fighting against tuberculosis, the World Health Organisation has estimated that around 1.7 million people died of tuberculosis in 2016 and over a quarter of the world’s population is infected. One of the critical hurdles for stopping tuberculosis transmission is early and effective diagnosis of patients with the active pulmonary disease. Although important innovations in molecular diagnosis have been recently developed (e.g. Xpert MTB/RIF, Cepheid Inc., USA), there are no suitable tests for population screening at point-of-care. The current tuberculosis diagnosis pipeline presents a highly variable performance and requires access to reference laboratory facilities. A non-sputum based rapid test with high specificity and sensitivity could save ~400,000 lives per year. Therefore, new biomarkers for diagnosis are urgently required for identifying patients with early symptoms and to expedite treatment. Variable sensitivity and specificity can be overcome using a combination of multiple biomarkers (5). Proteins, as ultimate biological effectors, are ideal candidates for diagnostic biomarkers; consequently, proteomic studies are a crucial platform for biomarker discovery in tuberculosis. This work aims to develop a multi-marker panel for tuberculosis diagnosis with high performance capable of differentiating tuberculosis patients from relevant controls. Quantitative Multidimensional Protein Identification Technology (qMudPIT) is applied for biomarker discovery identifying candidates for early diagnosis of tuberculosis. The multidimensional method optimised in this work led to the identification of 5022 plasma proteins and 3577 quantified proteins using iTRAQ labelling. Known and completely novel markers for active tuberculosis in plasma were identified including a peptide derived from Mycobacterium tuberculosis. Complementary statistical and bioinformatic analysis were applied to prioritise candidates for validation in one or two independent cohorts. The plasma proteomic profile here described represents a power strategy for biomarker discovery and the panel proposed has the potential to be translated to a rapid test and which might contribute to tuberculosis control.
Project description:The emergence of drug resistance among tuberculosis (TB) patients is often associated with their non-compliance to the length of the chemotherapy, which can reach up to 2 years for the treatment of multi-drug-resistant (MDR) TB. Drugs that would kill TB faster and would not lead to the development of drug resistance could shorten chemotherapy significantly. In Escherichia coli, the common mechanism of cell death by bactericidal antibiotics is the generation of highly reactive hydroxyl radicals via the Fenton reaction. Since ascorbic acid (vitamin C) is known to drive the Fenton reaction, we tested whether the Fenton reaction could lead to a bactericidal event in Mycobacterium tuberculosis by treating M. tuberculosis cultures with vitamin C. Here, we report that the addition of vitamin C to drug-susceptible, MDR and extensively drug-resistant (XDR) M. tuberculosis strains results in sterilization of the cultures in vitro. We show that the sterilizing effect of vitamin C on M. tuberculosis was dependent on the production of high ferrous ion levels and reactive oxygen species. Although, this potent sterilizing activity of vitamin C against M. tuberculosis in vitro was not observed in mice, we believe this activity needs further investigation. Comparison of vitamin C treated Mycobacterium tuberculosis transcriptome relative to untreated; Three biological replicates, second is a dye flip
Project description:The emergence of drug resistance among tuberculosis (TB) patients is often associated with their non-compliance to the length of the chemotherapy, which can reach up to 2 years for the treatment of multi-drug-resistant (MDR) TB. Drugs that would kill TB faster and would not lead to the development of drug resistance could shorten chemotherapy significantly. In Escherichia coli, the common mechanism of cell death by bactericidal antibiotics is the generation of highly reactive hydroxyl radicals via the Fenton reaction. Since ascorbic acid (vitamin C) is known to drive the Fenton reaction, we tested whether the Fenton reaction could lead to a bactericidal event in Mycobacterium tuberculosis by treating M. tuberculosis cultures with vitamin C. Here, we report that the addition of vitamin C to drug-susceptible, MDR and extensively drug-resistant (XDR) M. tuberculosis strains results in sterilization of the cultures in vitro. We show that the sterilizing effect of vitamin C on M. tuberculosis was dependent on the production of high ferrous ion levels and reactive oxygen species. Although, this potent sterilizing activity of vitamin C against M. tuberculosis in vitro was not observed in mice, we believe this activity needs further investigation.
2013-05-24 | GSE42293 | GEO
Project description:Extensively Drug-Resistant (XDR) Mycobacterium tuberculosis in Zhejiang, China
Project description:We report the application of RNA sequencing to assess the expression dynamics of miRNAs and their isoforms over time upon infection with a panel of six intracellular bacteria (Mycobacterium tuberculosis H37Rv, Mycobacterium tuberculosis Beijing strain GC1237, Mycobacterium bovis BCG, Salmonella typhimurium strain Keller, Staphloccocus epidermidis and Yersinia pseudotuberculosis)
Project description:Transcriptional profiling of SirR and manganese regulated expression of genes in Mycobacterium tuberculosis strains comparing high manganese vs. low manganese in Rv (wild type Mycobacterium tuberculosis) and ST70 (mntR mutant strain of Mycobacterium tuberculosis)