Competitive binding of scFv antibodies with HM-1 to nMAb-KT. ELISA plates coated with nMAb-KT were incubated with increasing concentrations of the selected scFv antibodies and the control scFv antibody as described in Materials and Methods. The symbols represent the respective binding of scFv antibodies (solid symbols) and HM-1 (open symbols) with nMAb-KT. •, scFv-A1; ▴, scFv-A2; ▪, scFv-A3; ♦, scFv-A4; ▾, control scFv antibody. The maximum binding activities (A405nm, absorption at 405 nm) of scFv-A1, -A2, -A3, and -A4 were 0.928, 0.968, 0.891 and 0.852, respectively.