Mycobacterial killing assay in Raw 264.7 macrophages

Abstract

Mycobacterial killing assay is an important method to determine mycobacterial pathogenesis and antimycobacterial response in host cells. In our study, we analyzed the survival of Mycobacterium abscessus in mouse macrophage cell line, Raw 264.7 cells. Mycobacterium abscessus survival in macrophages is measured through a multiple step process: (1) Infection of the cells with Mycobacterium abscessus for 1 hour, 24 hours and 72 hours, (2) Plating cell lysates on agar plates, (3) Incubating plates at 37oC, and (4) Counting colonies on the plates. We study Mycobacterium abscessus survival in host cells to gain knowledge on this disease and how it affects patients with cystic fibrosis and chronic obstructive pulmonary disease. Prevalence of this disease has increased over the years, especially drug-resistant mycobacterial strains. It becomes important to understand the interaction between the host and Mycobacteria. In our mycobacterial killing assay, we observed that Mycobacterium abscessus can adapt to grow successfully in Raw 264.7 cells. Further studies are needed to halt and reduce Mycobacterium abscessus growth within host cells.