Monoclonal antibodies against bovine β-casein:: Production and epitope characterization

Twenty-one murine monoclonal antibodies (MAbs) were raised against bovine beta -casein (beta -CN). They were discriminated by: (1) their specificity in ACP-ELISA towards beta -CN fragments and beta -CN from buffalo, ewe, goat, human and mare; and (2) their reactivity in BIAcore assays with bovine beta -CN. The antigen sequences were compared to delineate epitopes. The MAbs recognized 14 distinct epitopes clustered in six discrete determinants (4-8, 14-24, 33-48, 49-91, 178-183, 184-209). Within the determinants, all clustered epitopes except one were found to be overlapping by BIAcore additivity assay. Epitopes were delineated at position 4-8 and 178-183. One-quarter of the residues at both termini shared equally similar to 72% of the epitopes. No MAb was bovine-specific. A single MAb discriminated bovine whole casein from that of ewe and goat. Epitopes were included in each of the plasmin-released proteose peptone and gamma -CN peptides, and the panel of MAbs may thus provide probes suitable for their detection.