Project description:To understand nontuberculous mycobacterial (NTM) pathogenesis, we evaluated immune responses to Mycobacterium avium (Mav) in asymptomatic individuals with a previous history of M. avium complex lung disease (MACDZ). We analyzed global gene expression in paired Mav-infected and uninfected peripheral blood monocytes from 17 MACDZ and 17 healthy controls.
Project description:The incidence of pulmonary nontuberculous mycobacterial (PNTM) disease is increasing, but host susceptibility factors are not fully understood. We infected air-liquid interface (ALI) primary respiratory epithelial cell cultures with Mycobacterium avium complex (MAC) or Mycobacterium abscessus (MAB) and performed transcriptome sequencing (RNA-Seq) to identify relevant gene expression differences. We used cells from 4 different donors in order to try to obtain generalizable data. The differentiated respiratory epithelial cells in ALI were infected with MAC or MAB at MOI of 100:1 or 1000:1, and RNA-seq was performed at 1 and 3 days after infection. We found downregulation of ciliary genes, including several identified with polymorphisms in previous PNTM cohorts. The cytokine IL-32, the superpathway of cholesterol biosynthesis and downstream targets within the IL-17 signaling pathway were all elevated. The integrin signaling pathway was more upregulated by MAB than MAC infection. Working with primary respiratory epithelial cells infected with nontuberculous mycobacteria at ALI, we identified ciliary function, cholesterol biosynthesis, chemokine production and the IL-17 pathway as major targets of host responses to infection. Some of these pathways may be amenable to therapeutic manipulation.
Project description:Whole blood gene expression to predict susceptibility to nontuberculous mycobacterial pulmonary disease in adults with cystic fibrosis
Project description:Mycobacterium avium is the most common nontuberculous mycobacterium (NTM) species causing infectious disease. Here, we characterized a M. avium infection model in zebrafish larvae, and compared it to M. marinum infection, a model of tuberculosis. Using RNAseq analysis, we found a distinct transcriptome response in cytokine-cytokine receptor interaction for M. avium and M. marinum infection. In addition, we found substantial differences in gene expression in metabolic pathways, phagosome formation, matrix remodeling, and apoptosis in response to these mycobacterial infections.
