Creatine kinase isoenzyme--antibody reactions in immuno-inhibition and immunonephelometry.

I have raised, in rabbits, antibodies against MM and BB isoenzymes of creatine kinase. The antibodies produced were homogeneous by Ouchterlony double immunodiffusion and did not cross react with their opposite antigens. Both antisera, however, appeared to be mixtures of antibodies, displaying different equivalences for activation, inactivation, and, possibly, precipitation. Inactivation studies indicated the presence of antibodies effective against dimer only and antibodies effective against monomer or dimer. Both antisera cross reacted with MB and displayed antibodies that appeared to block only half of the activity as well as antibodies that blocked all of the activity. The antisera produced were useful for measuring MB by both immuno-inhibition and immunonephelometry, but neither appears to be advantageous over current electrophoresis or ion-exchange methods. A comparison of decay of MB in patients between activity and mass measurements indicated that activity decay is about 12-fold faster than mass decay.