Clinical Chemistry, Vol 24, 414-419, Copyright © 1978 by American Association for Clinical Chemistry

Radioimmunoassay of creatine kinase isoenzymes in human serum: isoenzyme MM

AC Van Steirteghem, MH Zweig and AN Schechter

Measurement of the mass concentration of serum enzymes by radioimmunoassay provides direct quantitation of specific isoenzymes and may be less subject to some of the limitations of traditional assay procedures for enzymes. We describe the development of a sensitive and specific radioimmunoassay for the muscle isoenzyme of creatine kinase, CM-MM, in human serum. CK-MM, purified from human skeletal muscle, was used to raise high-titer antisera and for iodination by the Chloramine T method. The radioimmunoassay required 50 microliter of sample, utilized a double-antibody separation method, and was completed in 24 h. Cross reactivity with CK-BB was virtually zero, 3--17% with CK-MB. The mass concentration of CK-MM in the serum of healthy subjects ranged from 36 to 1668 microgram/liter and correlated closely with total CK enzymatic activity. Serum concentrations of CK-MM from casually selected patients correlated less well with total CK enzymatic activity, suggesting the existence of other CK isoenzymes or the presence of inactive forms.

The following articles in journals at HighWire Press have cited this article:

				M. C. GEOKAS, R. S. YALOW, E. W. STRAUS, and E. M. GOLD Peptide Radioimmunoassays in Clinical Medicine Ann Intern Med, September 1, 1982; 97(3): 389 - 407. [Abstract] [PDF]

				M. H. Zweig, A. C. Van Steirteghem, and E. F. Torrey Creatine Kinase Isozymes in the Serum and CSF of Schizophrenic Patients Arch Gen Psychiatry, October 1, 1981; 38(10): 1107 - 1109. [Abstract] [PDF]