Interaction of mAb 11-1F4 with plate-immobilized, Ala-substituted Len(1–18) peptides. (a) Binding of 11-1F4 to Len(1–18), (▲); IA2, (○); V3A, (●); T5A, (Δ); D9A, (□); and P8A, (■). (b) Antibody binding to Len(1–18), (▲); I11A, (▽); V13A, (♦); S14A, (◊); and I15A, (×).