Figure 4.
B. mallei (Bm) and B. pseudomallei (Bp) are closely related species but activate TLR2 and TLR4 differently. Burkholderia spp. were grown at 37°C for ~48 h, and bacterial suspensions were diluted in PBS to inoculate HEK293-TLR2 or -TLR4 cells. The following Burkholderia spp. were evaluated: (A) TLR2: Bm FMH, Bp K96243, Bp 1106a, Bp 406e, Bp MSHR305, and Bp MSHR668; (B) TLR2: Bp 1026b, Bp MSHR 5855, Bp MSHR5848, Bp MSHR5858, Bp HBPUB10134a, and Bp HBPUB10303a. (C, D) are TLR4 incubated with the same strains as listed for (A, B), respectively. Media controls contained only PBS rather than bacterial cells and positive controls contained either HKLM cells (2 x 106 cells) for TLR2 or E. coli LPS (0.2 ng) for TLR4. All samples were analyzed in triplicate, and results represent one of two independent repeats. Results are presented as geometric mean with standard error of the mean. Significant values compared to media control are shown: *P ≤ 0.05; **P ≤ 0.01; ***P ≤ 0.001; ****P ≤ 0.0001; *****P ≤ 0.00001.