Studies of a human lambda-chain epitope related to a complementarity-determining region

A tryptic non-adecapeptide representing the 24-42 sequence of the MCG lambda-type Bence-Jones protein, and which contains its entire complementarity-determining region-1, was isolated. The peptide was utilized in preparing an affinity column that was used to isolate an antibody having the reactivity of a previously employed idiotypic antibody to MCG. This antibody preparation, as well as 13 monoclonal mouse antibodies to human lambda-chains, was employed in an enzyme-linked immunoassay to detect other Bence-Jones proteins with this serologic specificity. The results obtained with two of the monoclonal antibodies suggest that the epitope in question is a noncontiguous one.