FIG. 7.

Calcium influx and IL-1α secretion after treatment with recombinant LLO. Macrophages were treated with the indicated concentrations of recombinant LLO or 10 μM A23187, and the fluorescence intensity of Fluo-4 was measured to evaluate kinetics of the intracellular calcium concentration (A). Macrophages were cultured with various concentrations of LLO or 10 μM A23187 for 18 h, and the amount of LDH released from macrophages were measured (B). Macrophages were infected with the Δhly strain for 1 h and treated with various concentrations of LLO or 10 μM A23187 3 h later. The culture was continued for 15 h, and the amount of IL-1α in the culture supernatant was measured (C). In addition, the amounts of mature IL-1α in the culture supernatant and pro-IL-1α in the cell lysate were investigated by Western blotting (D).