Allergenic structure of allergen M from cod. II. Allergenicity of the limited tryptic hydrolysis peptides of fragment TM 2.

The peptides P1B3 (amino acid residues No. 88-113) and LT3N1 (residues No. 88-108), obtained from the limited tryptic hydrolysis of fragment TM 2 from codfish allergen M inhibited the interaction between allergen M and reaginic IgE antibodies both in vitro (87 and 62% RAST inhibition, respectively) and in vivo (total PK test inhibition). The peptide A7B1 (residues No. 97-113) overlapping the former at the COOH-terminus, was inactive in PK test inhibition experiments and produced only a minor inhibition of RAST (15%). The findings suggest that the nonapeptide residue No. 88-96 is partially indispensible for the allergenic activity of fragment TM 2, and is likely to incorporate allergenic determinant(s).