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

Abstract

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.

Kinetic Analysis of Synthetic Analogues of Linear‐Epitope Peptides of Glycoprotein D of Herpes Simplex Virus Type 1 by Surface Plasmon Resonance

“…The present kinetic study with surface plasmon resonance precisely defines the epitope at residues 11 -17 and shows that this linear fragment of gD binds mAb A16 with approximately the same affinity as the larger gD fragment [gD-(9-19)-peptide]. These results differ from the previous results obtained with a competition ELISA, when gD-(10-18)-peptide was found to be the smallest peptide able to inhibit binding of mAb A16 to a coat of gD-(9-21)-peptide [7]. An important difference in the studies is the peptides tested, since in the present study the epitope length was examined by means of peptide amides, whereas in the competition ELISA the epitope boundaries were examined by by means of peptides with a free COOH at the C-terminus.…”

“…The importance of Argl6 in the interaction with group V11 mAbs was previously shown in a competition ELISA with analogues of gD-(9-21)-peptide and in studies with HSV-1 mutants. The relative binding of mAb A16 to a peptide analogue of gD-(9-21)-peptide, in which Argl6 was substituted by His, was more than 200-fold reduced [7], and an HSV mutant resistant to neutralization by another group VII mAb LP14 has His instead of Arg at position 16 1211.…”

“…In a previous study, antigenic site VII of gD was located between residues 11 and 19 for another group VII antibody, mAb 170 [4]. In a previous study by our group, the boundaries of the epitopes for six group VII antibodies, including mAb A16, were determined by competition ELISA [7]. It was found that gD-(lO-I8)-peptide and gD-(9-17)peptide bound mAb A16, but the relative binding was 130-fold weaker than with gD-(9-21 j-peptide.…”

“…Immunization with synthetic peptides comprising this region of HSV gD protected mice against a lethal challenge with HSV [8, 91. Substitution studies showed that Pro14 and Argl6 are important for binding of mAb A16 [7]. Additional information on residues that interact with mAb A16 was obtained by screening a random peptide library displayed on a filamentous bacteriophage [lo] with the antibody.…”

Identification of the core residues of the epitope of a monoclonal antibody raised against glycoprotein D of herpes simplex virus type 1 by screening of a random peptide library

“…Here, we describe the application of a 1s-residue random peptide library in bacteriophage M13, for screening with mAb A16 [17], a group VII antibody [18] as a target. Affinity measurements of the native and phage-derived peptide with the mAb were performed using a biosensor based on the surface plasmon resonance (SPR) principle.…”