Heterophilic antibodies produce spuriously elevated concentrations of the MB isoenzyme of creatine kinase in a selected patient population.
Dual-site murine antibody-based immunoassays are commonly used in clinical laboratories to quantitate the MB isoenzyme of creatine kinase (CK-MB). Because the serum level of CK-MB is a relatively specific and sensitive indicator of myocardial ischemic damage, accurate quantitation is essential for a correct diagnosis. Heterophile antibodies (eg, human anti-murine antibodies) can interfere with these assays, however, and produce erroneous results. A subpopulation of 19 surgical patients with colorectal carcinoma who had received injections of an 125I-labeled murine monoclonal antibody directed against a tumor-associated glycoprotein was studied. Serum specimens from eight patients (42%) showed a marked increase in the level of CK-MB and normal total CK concentrations. The increased concentrations of CK-MB, which were attributed to interference by human antimurine antibodies, were substantially reduced in these specimens after a heterophile blocking reagent was added. However, this reagent did not significantly alter the serum level of CK-MB in patients who had clinical evidence of acute myocardial ischemia.
Sosolik
R C
RC
Ohio State University Medical Center, Columbus 43210, USA.
Hitchcock
C L
CL
Becker
W J
WJ
D000818:Animals; D000910:Antibodies, Heterophile / Q000008:administration & dosage / Q000627:therapeutic use*; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000627:therapeutic use; D000951:Antigens, Neoplasm / Q000276:immunology*; D001797:Blood Protein Electrophoresis; D002277:Carcinoma / Q000201:enzymology* / Q000628:therapy; D015179:Colorectal Neoplasms / Q000201:enzymology* / Q000628:therapy; D003402:Creatine Kinase / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005189:False Positive Reactions; D006023:Glycoproteins / Q000276:immunology*; D006801:Humans; D007527:Isoenzymes; D051379:Mice; D017202:Myocardial Ischemia / Q000201:enzymology; D011237:Predictive Value of Tests
D000910:Antibodies, Heterophile; D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D006023:Glycoproteins; D007527:Isoenzymes; C047052:tumor-associated antigen 72; D003402:Creatine Kinase