FIGURE 3.

R753Q TLR2 mediates impaired activation of NF-κB luciferase reporter in response to inactivated M. tuberculosis, S. aureus, mycobacteria-derived cell wall, and culture filtrate fractions, LAM and Pam3Cys. HEK293T cells were transiently transfected with pcDNA3-YFP plasmids encoding WT or R753Q TLR2, along with pELAM-Luc (NF-κB reporter) and pTK-Renilla-Luc (to normalize for transfection efficiency). A, after recovery for 24 h, cells were stimulated with irradiated M. tuberculosis (Mtb) or heat-killed S. aureus (HKSA) using inactivated bacteria/HEK cell ratios 50:1 and 10:1. B, HEK transfectants were treated for 5 h with medium or stimulated with 100 ng/ml Pam3Cys, M. tuberculosis-derived CW and culture filtrate (CF) fractions, and LAM (5 μg/ml each). Firefly versus Renilla luciferase activities were determined in cell lysates, and the numbers in bacteria- or lipid-stimulated cells were normalized to medium control values and presented as -fold induction. The summary of three experiments (mean ± S.D.) is shown. *, p < 0.05, **, p < 0.01, ***, p < 0.005.