ANTIBODIES AND T-CELLS AGAINST SYNTHETIC PEPTIDES OF THE C-TERMINAL DOMAIN (H-C) OF BOTULINUM NEUROTOXIN TYPE-A AND THEIR CROSS-REACTION WITH H-C

Seventeen peptides containing T cell and/or antibody (Ab) epitopes pre viously localized on H-c of botulinum neurotoxin type A were used in S JL and BALB/c mice as immunogens either individually or as an equimola r mixture of groups that contained epitopes of T cells, Abs or both, t o determine their abilities to generate T cells and/or Abs that recogn ize intact H-c. In SJL, peptide 897-915 which included both T cell and Ab epitopes, elicited Abs that cross-reacted very strongly with H-c. In BALB/c, peptides 869-887, 883-901, 981-999 and 1275-1296 which cont ained Ab epitopes generated Abs that cross-reacted strongly with H-c. A mixture of peptides that contained T cell and Ab epitopes was effect ive in both strains in eliciting T cells and Abs that cross-reacted wi th H-c. This mixture form gave a quicker rise (after two injections) i n cross-reactive (with H-c) Ab titer as compared to other peptide mixt ures or the individual peptides, and sustained in BALB/c a high Ab tit er upon further booster injections. Some of the regions that elicited crossreactive immunity to H-c have sequence similarity to other clostr idial toxins, suggesting that one or more of these synthetic peptides might provide cross-protection against those toxins. (C) 1998 Elsevier Science B.V.