We have previously shown ERK activation in the pancreas and lung in ligation-induced acute pancreatitis in mice.[3] Here we have shown that IL-33 increases ERK activation and CXCL2/MIP-2α, CCL2/MCP-1 and IL-6 production in mouse acinar cells and that specific inhibition of ERK with DN.ERK expression inhibits IL-33-induced cytokine production. The gene discussed is IL33; the disease is acute pancreatitis.