①Measured by its binding ability in a functional ELISA. Immobilized SIRPA at 2 μg/ml can bind human CD47, the EC50 of human CD47 protein is 65.91-82.42 ng/ml.
②Human SIRPA protein His/Myc tag captured on COOH chip can bind Human CD47 protein Fc tag with an affinity constant of 19.1 nM as detected by LSPR Assay.