Genetic modulation of tumor antigen presentation

An effective cancer-cell vaccine is created by expressing major-histocompat ibility-complex (MHC) class II molecules without the invariant chain protei n (li) that normally blocks the antigenic-peptide-binding site of MHC class II molecules at their synthesis in the endoplasmic reticulum. Such tumor-c ell constructs are created either by the transfer of genes for MHC class II alpha and beta chains, or by the induction of MHC class II molecules and I i protein with a transacting factor, followed by Ii suppression using antis ense methods. Preclinical validation of this approach is reviewed with the goal of using this immunotherapy for metastatic human cancers.