Induction of Antiviral Antibodies by DNA Immunization Requires neither Perforin-Mediated nor CD8(+)-T-Cell-Mediated Lysis of Antigen-Expressing Cells

DNA immunization induces antibodies to the encoded protein, which indicates that the protein must gain access to the extracellular milieu, allowing it to interact with naïve B lymphocytes. It has been suggested that antigen release may be effected by cytotoxic-T-lymphocyte-mediated lysis of transfected antigen-expressing cells; this might be particularly important for the induction of responses to a noncytopathic, cytosolic protein. Here we show that the induction of antibody responses to one such DNA-encoded protein required neither perforin nor CD8(+) T cells. In addition, there was no skewing of the immunoglobulin G isotypes in the absence of perforin.