Three-step purification of bacterially expressed human single-chain Fv antibodies for clinical applications

We have obtained a cell line which secretes a human monoclonal IgM (B7) reacting with the myosin heavy chain of human heart. We have constructed single-chain fragments (scFv) of B7. The scFv may be useful for the imaging of myocardial necrosis after myocarditis, cardiac drug toxicosis or graft rejection. The aim of our work was to purify the scFv for immunoscintigraphy. We describe several purification steps including immobilized metal affinity chromatography (IMAC), anti-c-myc monoclonal antibody affinity chromatography, size-exclusion chromatography with SuperdexR 75 HR 10/30 and ion-exchange chromatography (mini Q TM 30Q).