FIG. 1.

IFN-γ-inducing ability and cytotoxicity of full-length PLY with or without cholesterol treatment. To determine IFN-γ-inducing ability, normal spleen cells were stimulated for 24 h with PLY471 (full-length PLY) that had been treated with or without 10 μ g of cholesterol/ml and the level of IFN-γ in the culture supernatant was assayed by EIA. To determine cytotoxicity for spleen cells, cells were incubated with the same PLY471 preparations for 6 h, and the level of LDH released in the culture supernatant from the cells was measured. Each column represents the level of IFN-γ induced by PLY471 with (open column) or without (closed column) cholesterol, and each point connected by a line represents the cytotoxicity of cholesterol-treated (open squares) or nontreated (closed circles) PLY471. Data are shown as the mean of triplicate determinations ± the standard deviation (SD). The result shown here is the representative of three similar experiments.