Affinity Maturation by Chain Shuffling and Site Directed Mutagenesis

In the human immune system, antibodies with high affinities for antigen are created in two stages. A diverse primary repertoire of antibody structures is produced by the combinatorial rearrangement of germline V gene segments, and antibodies are selected from this repertoire by binding to the antigen (Alt et al. 1987). Antibody affinities are then further improved by somatic hypermutation and further rounds of selection (Allen et al. 1987).