Immunogenicity of microbial peptides grafted in self immunoglobulin molecules.

The advent of genetic engineering has allowed for the expression and production of recombinant proteins carrying short immunogenic epitopes of foreign antigens. These antigenized molecules represent valuable tools to investigate the molecular basis of antigen fragmentation, generation and presentation of peptide to lymphocytes, the induction of epitope specific immunity and potentially the development of a new generation of vaccines. Recently, we expressed viral epitopes on immunoglobulin molecules by replacing the D segment of a variable region of the heavy chain (VH) gene with a B cell epitope from the V3-loop of HIV-1 envelope protein, as well as a cytotoxic T lymphocyte (CTL) and a T helper epitope from influenza virus nucleoprotein and hemagglutinin, respectively. The T cell peptides generated from the immunoglobulin molecules produced by cells transfected with chimeric V genes, activated specific T cells as they do when generated from viral proteins. Possible practical applications for the development of prophylactic and immunotherapeutic reagents are envisioned for immunoglobulin molecules bearing foreign epitopes.