Differential Macrophage Response to Slow- and Fast-Growing Pathogenic Mycobacteria
Figure 3
Integrity of THP-1 macrophages monolayer after mycobacterial infection. THP-1 macrophages were infected with fast-growing (M. abscessus and M. fortuitum) or slow-growing mycobacteria (M. celatum and M. tuberculosis) using a MOI of 5. After 6 h of infection, cells were washed and incubated with fresh RPMI medium. Infection kinetics were stopped at 6 h, 12 h, 24 h, 48 h, and 72 h, fixed using 4% p-formaldehyde, and visualized by microscopy. Monolayer integrity of infected cells was compared with monolayer of noninfected macrophages. (a) Monolayer integrity percentage of infected macrophages. Large cell damage is shown within a blue box. : M. abscessus; : M. fortuitum; : M. celatum; : M. tuberculosis. The experiment was performed in triplicate and repeated on three independent occasions. (b) Microscope photographs of THP-1 macrophages at 48 h of infection with the indicated mycobacteria (600x, Kinyoun stain).
