Binding of mAb 11-1F4 to plate-immobilized Len(1–22) and phage peptides in the presence and absence of peptide inhibitors. (a) Binding of 11-1F4 to phage peptides or Len(1–22). (b) Competitive inhibition of 2 nM 11-1F4 binding to Len(1–22) in the presence of phage peptides or Len(1–22). The dashed line indicates 50% inhibition. a12, (▼); g4, (■); b2, (▽); a7, (□); and Len(1–22), (○).