ENHANCEMENT OF PEPTIDE IMMUNOGENICITY BY INSERTION OF A CATHEPSIN-B CLEAVAGE SITE BETWEEN DETERMINANTS RECOGNIZED BY B-CELLS AND T-CELLS

The insertion of two lysine residues (cleavage sites of cathepsin B) a t the boundary of a peptide recognized by B cells (BD) and a class-II- presentable sequence (TD(h)) enhanced the anti-BD antibody induction capacity of this type of peptide construct, as well as production of I L2. It is postulated that these lysines generate a neoprocessable site which helps in release of the TD(h) moiety from the construct, enabli ng its presentation to class II molecules, an essential step in clonal expansion of the antibody-producing B cell after internalization of t he construct via the BD moiety.