STUDIES ON HUMAN PORIN .6. PRODUCTION AND CHARACTERIZATION OF 8 MONOCLONAL MOUSE ANTIBODIES AGAINST THE HUMAN VDAC PORIN 31HL AND THEIR APPLICATION FOR HISTOTOPOLOGICAL STUDIES IN HUMAN SKELETAL-MUSCLE

We report on the production and characterization of eight monoclonal mouse antibodies against the complete human VDAC "Porin 31HL". The antigen used was purified from a total membrane preparation of the transformed human B-lymphocyte cell line H2LCL. In Western blots all eight mAbs react with a single 31-kDa band in solubilized H2LCL membrane preparations thus demonstrating their specificity for the human VDAC "Porin 31HL". Concerning the epitope specificity we show that all eight mAbs equally react with the N-terminal part of human porin. Moreover, we demonstrate the expression of VDAC in the sarcolemma by indirect immunoenzyme labelling of cryosections of human skeletal muscle applying four of our mAbs. These data support our recent observations on the expression of porin channels in the plasmalemma of different normal and transformed human cell lines. VDAC in the plasmalemma is discussed as the molecular basis of the Blatz and Magleby channel (Blatz, A.L. & Magleby, K.L. (1983) Biophys. J. 43, 237-241).