Isolation of Intracellular Pathogenic Bacteria from Infected Host Cells

Source: Sigal, N., et al. RNA Purification from Intracellularly Grown Listeria monocytogenes in Macrophage Cells. J. Vis. Exp. (2016).This video demonstrates the isolation of internalized pathogenic bacteria from infected bone marrow-derived macrophages (BMDMs). Bacteria are allowed to attach to host cells, and unattached bacteria are washed away. After internalization, an antibiotic is added to eliminate non-internalized bacteria. The host cells are lysed, centrifuged, and the supernatant is filtered to capture the bacteria on filter paper, which is flash-frozen and stored for further use.