Abstract: The invention provides a method of regulating a Th2 immune response which comprises contacting a cell with an amount of a molecule effective to modulate an ERK ½ pathway and/or a c-FOS pathway in the cell so as a to regulate the TH2 immune response, which molecule is any of (a) an agonist of a TLR2 or a TLR2 variant; (b) an agonist of an intracellular pathway that is initiated by activation of a TLR2; (c) an agonist of an intracellular pathway that is initiated by activation of a receptor activated by SEA; (d) an antagonist of an intracellular pathway that opposes TLR2 signaling or activation; (e) an agonist of an ERK ½ pathway; (f) an antagonist of a p38 pathway; (g) an antagonist of a JNK ½ pathway; or (h) an agonist of the c-FOS pathway, or a molecule that induces c-Fos gene expression, c-Fos messenger RNA stability, c-Fos protein induction, c-Fos protein stability, or c-Fos protein phosphorylation.