Origins of Antibody Diversity: Insights Gained from Amino Acid Sequence Studies of Elicited Antibodies

One of the great unsolved questions of im-munology is the mechanism ofB-cell diversification. Klinman et al. (this volume) suggest hat the ma-ture animal is able to manifest at least 107 antibody specificities. How is the information generated to create this number of structurally unique binding sites? Various lines of experimentation directed at answering this question have often provided contra-dictory results. Nucleic acid hybridization studies indicate that the number of germ-line variable (V)-region genes is relatively small (Leder et al., Tonegawa et al.; both this volume). The clear demonstration of inheritance of complementarity-region phenotypes (idiotypes) is incontrovertible evidence that germ-line genes for some V region