INDUCTION OF HUMAN CYTOMEGALOVIRUS (HCMV)-GLYCOPROTEIN B (GB)-SPECIFIC NEUTRALIZING ANTIBODY AND PHOSPHOPROTEIN 65 (PP65)-SPECIFIC CYTOTOXIC T-LYMPHOCYTE RESPONSES BY NAKED DNA IMMUNIZATION

Plasmids expressing the human cytomegalovirus (HCMV) glycoprotein B (g B) (UL55) or phosphoprotein 65 (pp65) (UL83) were constructed and eval uated for their ability to induce immune responses in mice. The full-l ength gB as well as a truncated form expressing amino acids 1-680 of g B, and lacking the fragment encoding amino acids 681-907 including the transmembrane domain of gB (gB680) were evaluated. Immunization of mi ce with plasmids coding for gB or gB680 induced ELISA and neutralizing antibodies, with the highest titres in mice immunized with the gB680 plasmid, Mice immunized with the gB plasmid predominantly produced IgG 2a gB-specific antibody, while the gB680 plasmid raised mostly IgG1 an ti-gB antibody. Mice immunized with the pp65 plasmid developed pp65-sp ecific cytotoxic T lymphocytes (CTL) and ELISA antibodies. Immunizatio n with a mixture of both gB and pp65 plasmids raised antibodies to bot h proteins and pp65-specific CTL, indicating a lack of interference be tween these two plasmids. These results suggest that DNA immunization is a useful approach for vaccination against HCMV disease. (C) 1998 El sevier Science Ltd. All rights reserved.