Regulatory effects of apoptosis-associated speck-like protein on cytokines in the P388D1 macrophage-like cell line.

Apoptosis-associated speck-like protein (ASC) is an adaptor molecule of caspase-1 activation that stimulates the secretion of multiple pro-inflammatory cytokines. We investigated the regulatory effects of ASC in the P388D1 macrophage-like cell line. Data showed that ASC overexpression induced by pEGFP-ASC-C2 transfection significantly increased caspase-1 expression and interleukin (IL)-1β and IL-6 secretion, but did not affect tumor necrosis factor (TNF)-α secretion. However, siRNA against ASC significantly decreased the caspase-1 expression and IL-1β and IL-6 secretion, but did not affect TNF-α secretion in the P388D1 cells. We suggest that ASC acts as an inflammatory response-associated gene by regulating caspase-1 activation and IL-1β and IL-6 secretion, which may correlate with its biological effects.