Project description:Transcriptional profiling of mycobacterium tuberculosis clinical isolates in China comparing extensively drug-resistant tuberculosis with drug sensitive one.
Project description:Transcriptional profiling of mycobacterium tuberculosis clinical isolates in China comparing extensively drug-resistant tuberculosis with drug sensitive one. The same condition experiment. The samples were from the different drug-resistant strains. Only one replicate.
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.
Project description:Mycobacterium tuberculosis (MTB) Beijing genotype is associated with high virulence and drug resistance worldwide. In Colombia, the Beijing genotype circulates since 1997 predominantly on the pacific coast, being the Beijing-Like SIT-190 more prevalent. This genotype conforms to a drug-resistant cluster and shows a fatal outcome in patients. To better understand virulence determinants, we performed a transcriptomic analysis with a Beijing-Like SIT-190 isolate (BL-323), and Beijing-Classic SIT-1 isolate (BC-391) in progressive tuberculosis (TB) murine model. RNA was extracted from mice lungs on days 3, 14, 28, and 60. On average, 0.6% of the total reads mapped against MTB genomes and of those, 90% against coding genes. The strains were independently associated as determined by hierarchical cluster and multidimensional scaling analysis. Gene ontology showed that in strain BL-323 enriched functions were related to host immune response and hypoxia, while proteolysis and protein folding were enriched in the BC-391 strain. Altogether, our results suggested a differential transcriptional program when evaluating these two closely related strains. The data presented here could potentially impact the control of this emerging, highly virulent and drug resistance genotype.
Project description:Tuberculosis continues as an important public health problem. Particularly considering Beijing-family strains of Mycobacterium tuberculosis, which have been associated with drug-resistance and hypervirulence. The Beijing-like SIT190 (BL) is the most prevalent Beijing strain in Colombia. The pathogenic mechanism and immune response against this pathogen is unknown. Thus, we compared the course of pulmonary TB in BALB/c mice infected with Classical-Beijing strain 391 and BL strain 323. The disease course was different among infected animals with Classical-Beijing and BL strain. Mice infected with BL had a 100% mortality at 45 days post-infection (dpi), with high bacillary loads and massive pneumonia, whereas infected animals with Classical-Beijing survived until 60 dpi and showed extensive pneumonia and necrosis. Lung RNA extraction was carried out at early (day 3 dpi), intermediate (day14 dpi), and late (days 28 and 60 dpi) time points of infection. Transcriptional analysis of infected mice with Classical-Beijing showed several over-expressed genes, associated with a pro-inflammatory profile, including those for coding for CCL3 and CCL4 chemokines, both biomarkers of disease severity. Contrary, mice infected with BL displayed a profile which included the over-expression of several genes associated with immune- suppression, including Nkiras, Dleu2 and Sphk2, highlighting an anti-inflammatory milieu which would allow high bacterial replication followed by an intense inflammatory response. In summary, both Beijing strains induced a non-protective immune response which induced extensive tissue damage, BL strain induced rapidly extensive pneumonia and death, whereas Classical-Beijing strain produced slower extensive pneumonia later associated with extensive necrosis.