Fig. 4.

The V3 loop is involved in gp120 LAV-induced NLRP3 inflammasome activation. a Production of IL-1β from BV2 cells stimulated with gp120 LAV (0.5 μg/ml) or increasing doses of heat-inactivated gp120 LAV (0.5–2 μg/ml) for 24 h. b, c ELISA of IL-1β (b) and western blots of Casp-1-p20 and IL-1β-p17 (c) in supernatants of BV2 cells stimulated with gp120 LAV (0.5 μg/ml) or the different variable loop peptides (V1–V5 loops, 0.2 μg/ml) for 24 h. NLRP3, pro-caspase-1, and pro-IL-1β in cell lysates (Lys) were also detected. d Immunoblot analysis of ASC in crosslinked pellets (upper panel) and cell lysates (lower panel) of BV2 cells stimulated with gp120 LAV (0.5 μg/ml) or the different variable loop peptides (V1–V5 loops, 0.2 μg/ml) for 24 h. e IL-1β in supernatants of BV2 cells treated with gp120 LAV (0.5 μg/ml) or V3 loop peptide (0.2 μg/ml) in the absence or presence of Z-YVAD-fmk (20 μM). The data are displayed as the mean ± SEM (n = 5) from three independent experiments (a, b, e). Western blot results are representative of two (d) and three (c) independent experiments. ***P < 0.001; NS, no significance