Cloning genes encoding MHC class II-restricted antigens: mutated CDC27 as a tumor antigen.

An approach was developed that allows the screening of an invariant chain-complementary DNA fusion library in a genetically engineered cell line expressing the essential components of the major histocompatibility complex (MHC) class II processing and presentation pathway, which led to the identification of a mutated form of human CDC27 which gave rise to an HLA-DR4-restricted melanoma antigen.