Skip to main content
. 2018 Apr 19;13(4):e0196120. doi: 10.1371/journal.pone.0196120

Fig 8. Intra- and extracellular neutrophil killing of M. abscessus.

Fig 8

Neutrophils (n = 7) were pre-incubated with DNase (100 units/ml) or DPI (10 μM), or left untreated (C). Neutrophils were exposed to (A) smooth (n = 6) or (B) rough M. abscessus (n = 7) for 1h, and surviving mycobacteria were compared to the initial infection. (C) Neutrophils (n = 7) were treated with cytochalasin D (cytoD; 5 μg/ml) or left untreated (C) and killing of smooth (closed bars) and rough (open bars) M. abscessus was assessed after 1h. Panels A-C were analyzed by t-test; *P<0.05. (D) Targeting of M. abscessus, without regard for morphotype, by cell-free conditioned media (CM) from neutrophils treated with smooth M. abscessus (Sm) or rough M. abscessus (R), and represents composite data from E and F. Data analysis by paired t-test; n = 14. Morphotype-specific targeting of (E) smooth or (F) rough M. abscessus by conditioned media (CM) from neutrophils treated with smooth M. abscessus (Sm), rough M. abscessus (R), or peptidoglycan (PGN); conditioned media were incubated at 95°C, as indicated, before killing assays. Killing of each morphotype was normalized to that of M. abscessus exposed to supernatants from untreated neutrophils. Data were analyzed by two-way ANOVA; n = 7; an interaction (P = 0.01) was found for heat-treatment of CM for targeting rough M. abscessus (F), but not smooth (E).