This invention provides compositions and methods for inducing and
enhancing immune responses, such as antigen-specific cytotoxic T
lymphocyte (CTL) responses, using chimeric molecules comprising
endoplasmic reticulum chaperone polypeptides and antigenic peptides. In
particular, the invention provides compositions and methods for enhancing
immune responses induced by polypeptides made in vivo by administered
nucleic acid, such as naked DNA or expression vectors, encoding the
chimeric molecules. The invention provides a method of inhibiting the
growth of a tumor in an individual. The invention also provides novel
self-replicating RNA virus constructs for enhancing immune responses
induced by chimeric polypeptides made in vivo.