Conjugates of Synthetic Lymphocyte-Activating Lipopeptides with Segments from HIV Proteins Induce Protein-Specific Antibody Formation

Abstract
Lipopeptide analogues of bacterial lipoprotein activate macrophages and B lymphocytes. The products formed by coupling these lipopeptides to low molecular mass antigens can be used to induce antigen-specific antibodies in mice. In the present work, it is shown that HIV-1 gp160-derived synthetic oligopeptides coupled to the synthetic lipodipeptide N-palmitoyl-S-[2,3-bis(palmitoyloxy)-(2RS)-propyl]-(R)-cysteinyl-seryl serine (P3CSS) induce peptide-specific antibodies in mice without adding further adjuvants. Depending on the peptides applied, the conjugates exhibited different lymphocyte stimulatory activity, immunoglobulin isotope patterns, and boost reactions; lipopeptide conjugates inducing a pronounced secondary immune response are considered to possess both B- and T-cell epitopes. Antibodies induced by the lipopeptide-HIV-1-peptide conjugates were also reactive against the recombinant gp160 of HIV-1.