DERIVATION AND APPLICATION OF MONOCLONAL-ANTIBODIES RECOGNIZING SEVERAL EPITOPES ON BOVINE SERUM-ALBUMIN

Three(AB-3, AB-4 and AB-6) monoclonal antibodies (mAb) to bovine serum albumin (BSA) were derived and characterized for their physicochemica l and immunological properties. AB-3 recognized an epitope distinct fr om epitopes recognized by AB-4 and AB-6 as determined by binding inhib ition assay. AB-4 and AB-6 mAbs recognized similar but not identical e pitopes on BSA. Based on the antigenic specificity, we applied these m Abs to quantitative analysis of BSA in medium and to depletion of BSA from culture medium containing fetal calf serum (FCS). For quantitativ e analysis, we employed a sandwich enzyme-linked immunosorbent assay ( ELISA) using biotinylated AB-3, solid-phase of AB-6 and an avidin-biot in-peroxidase complex system. This assay was highly sensitive and quan titative in the range of BSA concentration at 10 to 1,500 ng/ml. To de plete BSA from medium, we prepared affinity-gel coupled to AB-6. Repea ted treatment of FCS-containing medium with the affinity-gel efficient ly depleted BSA from the medium. The depletion capacity was 0.74 to 1. 0 moles of BSA/mole of coupled mAb.