Figure 4. ELISA experiments. Schematic (A) and structural (B) views of the constructs are shown. Human specific residues are indicated in white; * indicates the position of the G-D-P-L unresolved loop. Calculated surface of humanized areas are 1 467 Å2, 2 068 Å2 and 2 407 Å2 for 1/3D1, 2/3D1, and 2/3D1mutD2, respectively. (C) Double sandwich ELISA experiment with H27K15 mAb. The purified chimeric proteins were coated on plate and incubated in the presence of either H27K15 (dark gray bars) or PBS (light gray bars). Bound H27K15 was revealed with an anti-Fc human-HRP antibody followed by TMB incubation.