Desorption of antigenantibody complexes bound to immobilized Protein A by isoelectric focusing (abstract)
- B. W. Maidment, Jr., L. D. Papsidero, T. M. Chu
- Fed. Proc.,
A new technique for the recovery of immunologically reactive antibodies and putative antigens from breast cancer-associ ated immune complexes was described. Soluble immune com plexes were isolated from extracellular fluids by 2.5% poly ethylene glycol fractionation and affinity chromatography on Protein A:Sepharose CL-4B. The immune complexes bound to immobilized Protein A were then subjected to preparative isoelectric focusing. The dissociated immunoglobulins and puta tive antigens were recovered from the appropriate pH regions of the preparative isoelectric focusing gel. G-type immunoglob ulins recovered from immune complexes isolated from a breast cancer patient bound to the recovered putative antigen(s) and three breast cancer cell culture lines, but these immunoglobu lins did not bind to carcinoembryonic antigen or other cancer cell culture lines originating in colon, pancreas, prostate, or lymphoblast. The recovered putative antigens had Â¡soelectric points between pH 3.0 and 5.0 and molecular weights of 20,000 and 42,000.