Fig. 4

Analysis of processed state of products of caspase 1. Mice (5–6 per group) were challenged with LPS (500 µg i.p.) followed 1 hr later by treatment with IDN 1529, IDN 1965, or vehicle 2. Sera were collected 3 hr after LPS administration, pooled, immunoprecipitated, and immunoblotted with antibodies against mouse IL-1β (A) or IL-18 (B). In A, standards included rIL-1β and lysate from peritoneal macrophages exposed to LPS in vitro for 4 hr as a source of pro-IL-1β. In B, standards included rIL-18 and macrophage lysate prepared as in A as a source of pro-IL-18. (A,B) Bands migrating at ∼27 kD represent light chain from the antibodies used for immunoprecipitation. Experiments were performed twice with similar results.