Dsg3-specific immunization of the HLA tg mice allows cellular characterization and therapeutic intervention studies in a preclinical setting (i.e., during the formation of antigen-specific T and B cells and subsequent auto-Ab formation) or a therapeutic setting (i.e., after the onset of immunization with an ongoing auto-Ab formation as in human PV). The gene discussed is DSG3; the disease is acquired polycythemia vera.