Analogues of peptide 9-21 of glycoprotein D of herpes simplex virus and their binding to group VII monoclonal antibodies.

Several analogues of the amino acid sequence of peptide 9-21 of glycoprotein D of herpes simplex virus type 1 (HSV-1) were synthesized and investigated for reactivity with different group VII monoclonal antibodies, Mabs LP14, ID3, 170, HD4, A16, EII-24 and Ev-10, in a competition enzyme-linked immunosorbent assay (ELISA). Replacement of Arg at position 16 by His resulted in a loss of binding with the group VII Mabs. Substitution of Pro at residue 14 by Leu gave a reduced binding for a number of Mabs and loss of binding for Mab A16. Substitution of Lys at position 10 by Glu gave reduced binding for three out of the seven Mabs. In addition substitutions of Met at position 11 by norleucine and oxidized Met were studied. The boundaries of the epitope cluster were mapped by studying synthetic variants of peptide 9-21 which were shorter either at the C-terminus or at the N-terminus, or both. Peptide 10-18 and peptide 9-17 were the shortest peptides, which were still reactive with the group VII Mabs. Mab HD4 requires the N-terminus of peptide 9-21 for effective binding, while for binding of other Mabs contribution of the residues in the C-terminal part of this peptide is more important.