Lentiviral vector encoding cytomegalovirus protein identifies epitopes.

2004 SEP 1 - (NewsRx.com & NewsRx.net) -- Investigators have used a lentiviral vector encoding a human cytomegalovirus chimeric IE1-pp65 protein for epitope identification in HLA-transgenic mice.

"H2-deleted, HLA-A2, or HLA-B7 transgenic mice were used to identify new human cytomegalovirus (HCMV)-derived major histocompatibility complex class I-restricted epitopes. Three different approaches for mice immunization were compared for their ability to induce a cytotoxic CD8+ T cell (CTL) response: inoculation of infectious HCMV, injection of immunogenic synthetic peptides, and infection with a newly designed HIV-derived central DNA flap positive lentiviral vector encoding the chimeric IE1-pp65 protein (Trip-IE1-pp65). Targets pulsed with either known immunogenic peptides or computer predicted ones were used to characterize CTL," scientists writing in the journal Human Immunology report.

"Most of the mice immunized with the pp65 (495-NLVP-MVATV-503) immunodominant peptide responded after one injection whereas only two of six mice responded to two successive inoculations with HCMV," stated Pierre S. Rohrlich at INSERM U563 and collaborators throughout France. "Infection of mice with Trip-IE1-pp65 induced activation and expansion of CTL directed against peptides from both pp65 and IE1 and allowed identification of new epitopes. We further demonstrated the high capacity of monocyte-macrophage cells transduced with Trip-IE1-pp65 to activate and ...