EFFICIENT BISPECIFIC MONOCLONAL-ANTIBODY PURIFICATION USING GRADIENT THIOPHILIC AFFINITY-CHROMATOGRAPHY

Bispecific monoclonal antibodies (bsMAbs), due their unique design, ha ve a wide range of potential applications in immunodiagnostics and imm unotherapy. One of the major limitations for the use of bsMAbs produce d by hybrid-hybridomas is the concomitant production of parental monos pecific antibodies. The relative amount of bsMAb secreted may vary bet ween different hybrid-hybridomas. Hence, the purification of the desir ed bispecific molecule from other forms is crucial. Current purificati on methods include anion-exchange, HPLC on different matrices, and dua l affinity methods. Most of those methods include multiple steps and h ave limitations on the purity or yield of the desired species. We repo rt here a simple single-step purification method, using inexpensive th iophilic chromatography. This new method can potentially be scaled up, for industrial proposes. Finally, based on the amino acid sequences a nd assembly of the two heavy chains we attempt to explain the possible mechanism by which thiophilic chromatography was able to resolve the bsMAbs from the monospecific species. (C) 1998 Elsevier Science B.V. A ll rights reserved.