Introduction: gene vaccination, current concepts and future directions

Abstract

Intramuscular (i.m.) inoculation with plasmid (p) DNA encoding a specific antigen (gene vaccination) has been shown to induce both antibodies and cytotoxic T lymphocyte (CTL) responses [12, 23, 37, 40, 41]. In different models of viral diseases, in which challenge of immunized animals with virulent virus is possible, these responses have been found to be protective [28, 37]. Antibodies have been raised in various species (e.g., chickens, mice, ferrets, cattle and non-human primates) by the injection of pDNA that encode various antigens such as: hemagglutinin [37], matrix protein and nucleoprotein from the influenza virus [9], glycoprotein (gp) 120 and pg160 from the HIV-1 ([40, 41] and Kim et al. in this issue), gIV from bovine herpes virus [7], surface gp from rabies virus [43], hepatitis B virus (HBV) surface antigen ([8, 14] and Davis et al. in this issue), the malaria sporozoite protein ([16] and Hedstorm et al. in this issue), the heat-shock protein (hsp) 65 antigen from mycobacteria tuberculosis ([36] and Lowrie et al. in this issue), and hepatitis C virus (HCV) core antigen ([15] and Inchauspe in this issue). The immune response induced by injection of pDNA-encoded viral antigens persisted more than 12 months in Rhesus monkeys [9, 40, 41].