Figure 4
Impact of the strain background on the ClpC effect on intracellular survival of S. aureus in non-professional phagocytes. HaCaT and EA.hy926 cells were infected with the S. aureus strains LS1 (a), Newman (b), SH1000 (c) (WT; black bars), and the isogenic clpC mutants (clpC; white bars) at a MoI of 100, respectively, and co-cultured for 90 min. Extracellular and adherent bacteria were subsequently removed by washing and lysostaphin/gentamicin treatment, and the infected cell lines cultured for up to 168 h in cell culture medium supplemented with gentamicin. At the time points indicated, cells were removed, lysed by sonication, and surviving bacteria in lysates determined by plate counting. Data are presented as mean + SD (n = 6 biological replicates). *P < 0.05; **P < 0.01 (Mann-Whitney U test between WT and isogenic clpC mutant at a given time point). TpL/G, time post lysostaphin/gentamicin treatment.
