Project description:Tuberculosis (TB) is one of the deadliest infectious disorders in the world. To effectively TB manage, an essential step is to gain insight into the lineage of Mycobacterium tuberculosis (MTB) strains and the distribution of drug resistance. Although the Campania region is declared a cluster area for the infection, to contribute to the effort to understand TB evolution and transmission, still poorly known, we have generated a dataset of 159 genomes of MTB strains, from Campania region collected during 2018-2021, obtained from the analysis of whole genome sequence data. The results show that the most frequent MTB lineage is the 4 according for 129 strains (81.11%). Regarding drug resistance, 139 strains (87.4%) were classified as multi susceptible, while the remaining 20 (12.58%) showed drug resistance. Among the drug-resistance strains, 8 were isoniazid-resistant MTB (HR-MTB), 7 were resistant only to one antibiotic (3 were resistant only to ethambutol and 3 isolate to streptomycin while one isolate showed resistance to fluoroquinolones), 4 multidrug-resistant MTB, while only one was classified as pre-extensively drug-resistant MTB (pre-XDR). This dataset expands the existing available knowledge on drug resistance and evolution of MTB, contributing to further TB-related genomics studies to improve the management of TB infection.
Project description:This is a four dimensionsal ordinary differential equation mathematical model that explores the contribution of PI3P during Mycobacterium tuberculosis (Mtb) phagocytosis. The model was built in an effort to understand the mechanisms by which Mtb eliminates phagosome-lysosome fusion during the hosts enactment of anti-microbial pathways.
Project description:Latent tuberculosis infection (LTBI) relies on a homeostasis of macrophages and Mycobacterium tuberculosis (Mtb). The small heat shock protein, Mtb Hsp16.3 (also known as latency-associated antigen), plays an important role in Mtb persistence within macrophages. However, the mechanism of LTBI remains elusive. The aim of this study was to delineate LTBI-related miRNA expression in U937 macrophages expressing Mtb Hsp16.3 protein. This study intends to explore the potential function of miRNAs in the interaction of macrophages with Mtb Hsp16.3 and provide insights for investigating the role of macrophage homeostasis in LTBI.
Project description:Reports on common mutations in neuroendocrine tumors (NET) are rare and clonality of NET metastases has not been investigated in this tumor entity yet. We selected a NET and a the corresponding lymph node and liver metastases as well as the derivative cell lines to screen for somatic mutations in the primary NET and to track the fate of genetic changes (by Affymetrix SNP 6.0 micorarray and targeted resequencing by 454 GS FLX) and during metastasis and in vitro progression. using Affymetrix SNP 6.0 Arrays.
Project description:The purpose of this study was to identify Mtb- and hsa-encoded miRNAs produced in infected macrophages. RNA from 9 THP-1 samples (3 were uninfected, 3 were infected with Mtb H37Rv for 3 days and 3 were infected with Mtb H37Rv for 6 days) was sequenced and miRNAs were detected.
Project description:The cytokine IL-10 antagonizes pathways that control Mycobacterium tuberculosis (Mtb) infection. Nevertheless, the impact of IL-10 during Mtb infection has been difficult to decipher because loss of function studies in animal models have yielded only mild phenotypes. We have discovered that the transcription factor Bhlhe40 is required to repress Il10 expression during Mtb infection. Loss of Bhlhe40 in mice results in higher Il10 expression, higher bacterial burden, and early susceptibility similar to that observed in mice lacking IFN-g. Deletion of Il10 in Bhlhe40-/- mice reverses these phenotypes. Bhlhe40 deletion in T cells or CD11c+ cells is sufficient to cause susceptibility to Mtb. Bhlhe40 represents the first transcription factor found to be essential during Mtb infection to specifically regulate Il10 expression, revealing the importance of strict control of IL-10 production by innate and adaptive immune cells during infection. Our findings uncover a previously elusive but significant role for IL-10 in Mtb pathogenesis.
Project description:Respiratory ATP-synthesis is at present the only known mechanism for ATP synthesis in Mtb. This makes Mtb particularly vulnerable to inhibition of respiratory ATP synthase inhibitors such as TMC207, a novel compound for treatment of tuberculosis. We now provide first evidence that Mtb possesses a pathway that is fermentative in nature that could compensate lack of respiratory ATP synthesis. We identified acetate as a fermentation product in Mtb. Production of acetate was mediated by phosphotransacetylase (Pta) and acetate kinase (AckA). In acetate fermenting Mtb cultures, ATP levels remained stable despite inhibition of respiratory ATP synthase. Deletion of the PtaAckA pathway in Mtb decreased ATP content and impaired survival. This study provides evidence that in Mtb substrate level phosphorylation can compensate lack of oxidative phosphorylation, and thus facilitates survival of Mtb in the absence of respiration. Acetate fermentation contributes to adaptation to respiration-limiting conditions, and plays an important role in the emerging field of fermentative metabolism of Mtb. We performed DNA microarray analysis to validate the reduction of oxygen concentration by comparing aerobic and hypoxic cultures. RNA was prepared from Mtb after two days of cultivation in aerobic and in hypoxic cultures. At each condition, Mtb were cultured in medium supplemented with glycerol and glucose. Labelled cDNA from three independent experiments was subjected to array analysis.
Project description:Mycobacterium tuberculosis (Mtb) is evolutionarily equipped to resist exogenous reactive oxygen species but shows vulnerability to an increase in endogenous ROS (eROS). Since eROS is an unavoidable consequence of aerobic metabolism, understanding how Mtb manages eROS levels is essential yet needs to be characterized. By combining the Mrx1-roGFP2 redox biosensor with transposon mutagenesis, we identified 368 genes (redoxosome) responsible for maintaining homeostatic levels of eROS in Mtb. Integrating redoxosome with a global network of transcriptional regulators revealed a hypothetical protein (Rv0158) as a critical node managing eROS in Mtb. Disruption of rv0158 (rv0158 KO) impaired growth, redox balance, respiration, and metabolism of Mtb on glucose but not on fatty acids. Importantly, rv0158 KO exhibited enhanced growth on propionate, and the Rv0158 protein directly binds to methylmalonyl-CoA, a key intermediate in propionate catabolism. Metabolite profiling, ChIP-Seq, and gene-expression analyses indicate that Rv0158 manages metabolic neutralization of propionate toxicity by regulating the methylcitrate cycle. Disruption of rv0158 enhanced the sensitivity of Mtb to oxidative stress, nitric oxide, and anti-TB drugs. Lastly, rv0158 KO showed poor survival in macrophages and persistence defect in mice. Our results suggest that Rv0158 is a metabolic integrator for carbon metabolism and redox balance in Mtb.
Project description:In our rabbit model of pulmonary tuberculosis, infection with Mtb HN878, a hyper-virulent W-Beijing strain, results in progressive cavitary disease. However, infection of rabbit lungs with Mtb CDC1551, a hyper-immunogenic strain is effectively controlled overtime, establishing latent Mtb infection. Using these two Mtb strains, we tested the hypothesis that the initial host response in the lungs within hours of infection determines later outcome. The microarray experiments was performed to identify gene expression changes in the Mtb-HN878 or CDC1551- infected rabbit lungs at 3 hours post infection, compared to uninfected naïve rabbit lungs. New Zealand White rabbits were infected with Mtb HN878 or CDC1551 at ~3.5log10. At 3 hours post infection, lung tissue from Mtb-infected and uninfected rabbits were isolated and used for total RNA extraction. Total rabbit lung RNA was used for microarray analysis to determine infection induced changes in host gene expression.