TLR ligands do not generate calcium signals. IgE-primed MC/9 cells and BMMCs were loaded with Fura-2 and then stimulated or not (NS) with 20 ng/mL antigen (Ag), 1 μg/mL P3C, 100 ng/mL LPS, 100 ng/mL MALP2, or 10 μg/mL PGN, individually or in combination as indicated. Arrows indicate time of addition of stimulant(s). Values are expressed as the ratio of Fura-2 fluorescence at 510 nm when cells were excited alternately at 340 nm and 380 nm. The results are representative of 3 or more separate experiments.