FIG. 5.
TLR2 is essential for TNF-α secretion induced by Lactobacillus spp. (A) Splenic mononuclear cells were isolated from TLR2 gene-disrupted mice, along with the control (TLR2+/−). The cells (2 × 106 cells/ml) were stimulated with the indicated amounts of heat-killed L. fermentum and L. casei, synthetic lipoprotein, or synthetic lipid A. After 12 h of incubation, the TNF-α concentration in the supernatants was measured by ELISA. Measurements were done in triplicate, and the averages and the SD values are shown. The experiment was repeated three times, yielding similar results, and a typical result is shown. (B) Splenic mononuclear cells from C3H/HeN and its variant, C3H/HeJ. The cells were treated as in panel A. The TNF-α concentration in the supernatants was measured in triplicate, and the averages and the SD values are shown. The experiment was repeated three times producing similar results, and a typical result is shown.