Figure 2
MoDC apoptosis induced by successive challenge of influenza virus and pneumococcus. (A) MoDCs were infected with H1N1 at MOI 0.1. The percentage of apoptotic cells was examined at 24 hr, 30 hr or 48 hr after virus infection. (B) MoDCs were treated with heat killed pneumococcus at 1 × 106, 5 × 106 or 10 × 106 CFU. The percentage of apoptotic cells was examined at 24 hr after pneumococcal stimulation. (C-D) MoDCs were concurrently or successively challenged by both influenza virus and heat killed pneumococcus. (C) MoDCs were first infected with H1N1 at MOI 0.1 for 0 hr, and then immediately treated with 5 × 106 CFU heat killed pneumococcus for another 24 hr. The total incubation time at harvest was 24 hr. Alternatively, MoDCs were first infected with H1N1 at MOI 0.1 for 6 hr or 24 hr, and then treated with 5 × 106 CFU heat killed pneumococcus for another 24 hr to make up a total incubation time at harvest of 30 hr or 48 hr respectively. (D) MoDCs were infected with H1N1 at MOI 0.1 for 6 hr, and then treated with 1 × 106, 5 × 106 or 10 × 106 CFU heat killed pneumococcus for another 24 hr, with a total incubation time at harvest was 30 hr. Data (n = 6) represented mean ± SD of five individual experiments. Please note that some groups of data were presented twice in different panels for easy interpretation. *p < 0.05, **p < 0.01, ***p < 0.001 (ANOVA) and ##p < 0.01 (Post test for trend).