Figure 3.

Appropriate serum dilution. RS-ATL8 cells were sensitized with serial dilution of pooled healthy donor's serum overnight. Cells were stimulated with 1 μg/ml anti-human IgE (closed circles), or solvent alone (open circles) for 3 h. (A) IgE crosslinking–induced luciferase expression by anti-human IgE; (B) Cytotoxicity of human serum on the RS-ATL8 cells revealed by lactate dehydrogenase release. Dashed line in a, two-fold level of background (control without serum) luciferase expression. Data are means ± SEM (n = 4). *P < 0.05, **P < 0.01 (Dunnett's test).