Project description:Validation of gene expression levels to assess classification of TB patients and healthy controls qPCR gene expression profiling. Whole blood gene expression from TB patients (positive in GenXpert assay) and healthy controls; both tuberculin skin test positive (TSTpos) and -negative (TSTneg).
Project description:The aim of this study was to compare the transcriptional response to TB in regions of different incidence / prevalence. Experimental Design: Whole blood collected in tempus tubes from patients with different spectra of TB disease. All patients were sampled prior to the initiation of any antimycobacterial therapy. Active Pulmonary TB: PTB - All patients confirmed by isolation of Mycobacterium Tuberculosis on culture of sputum. Latent TB: LTB - All patients were screened at a tuberculosis clinic. All were positive by Interferon-Gamma Release assay(IGRA); specifically Quantiferon Gold In-Tube Assay (Cellestis, Australia). Latent patients had no clinical, or microbiological evidence of active infection and were asymptomatic. Experimental Variables: Patient group: Active PTB; Latent TB. There are no healthy controls in this dataset as it was being used for validation only. Controls: Latent TB individuals are used as a control for PTB in this dataset since there are few to no unexposed adult controls in Cape Town.
Project description:Most individuals infected with Mycobacterium tuberculosis can control the infection by forming and maintaining TB granulomas at the local infection foci. However, when the chronic infection (also known as latency) becomes active, the caseous center of TB granuloma enlarges, and it liquefies and cavitates, ultimately releasing bacilli into airway. Deciphering how genes are regulated within TB granulomas will help to understand the granuloma biology. Therefore, we performed genome-wide microarray on caseous human pulmonary TB granulomas and compared with normal lung tissues.
Project description:Transcriptome microarray analysis was conducted to examine the gene expression profiling of PBMCs from active TBs and HCs. All 18,853 mRNAs in the microarray were used to draw a Heatmap of differential genes according to their expression levels. The genes that exhibited significant changes in expression were used for further validation. The TB group (n=15) exhibited a significantly different profile compared to the HC (n=15) group (Fig. 1a). A total of 1,595 differentially expressed mRNAs were identified between the two groups. Of these, 335 mRNAs were up-regulated (fold change ≥ 2), and 1,260 mRNAs were down-regulated (fold change ≥ 2).