FIG. 8.

Effect of 90% normal human serum on the viability of the A. baumannii strains 307-0294, 853, 855, 900, and 979 in vitro. Assays were performed as described in Materials and Methods. All strains were also assessed in the presence of 90% heat-inactivated (56°C for 30 min) normal human serum, and their growth rates were similar; therefore, these data are not shown. The survival of 853 and 900 was significantly decreased compared to that of 307-0294, 855, and 979. Data are means ± standard errors of the means for n = 4 to 6. *, 853 compared to 307-0294, 855, and 979. P is <0.0001 for all comparisons between 853 and 307-0294 and 979. P is <0.0001, 0.0006, and 0.002 for 853 compared to 855 for 1, 2, and 3 h, respectively. #, 900 compared to 307-0294, 855, and 979. P is < 0.0001, 0.0006, and <0.0001 for 900 compared to 307-0294; P = 0.002, 0.008, and 0.009 for 900 compared to 855; P = 0.0004, <0.0001, and < 0.0001 for 900 compared to 979 for 1, 2, and 3 h, respectively.