The Binding Activity of Human CXCR4 with Anti-CXCR4 recombinant Antibody. Activity: Measured by its binding ability in a functional ELISA. Immobilized Human CXCR4 (CSB-MP006254HU(F1)) at 10 μg/mL can bind Anti-CXCR4 recombinant antibody, the EC<sub>50</sub> is 101.7-253.6 ng/mL.