Detection and quantitation of the beta-subunit of human chorionic gonadotropin in serum by radioimmunoassay.
Qualitative and quantitative radioimmunoassays (RIA) specific for the beta-subunit of human chorionic gonadotropin (HCG) produced by Wampole Laboratories and Monitor Science Corporation were compared in a study involving the sera from 213 individuals. Qualitative assays from both manufacturers were found to be equivalent in clinical specificity (99.2%). However, the clinical sensitivity of the Wampole beta-Tec qualitative RIA (95.6%) was greater than that of the Monitor Science beta-CG qualitative RIA (89%) in detecting hCG in serum. In quantitative assays, the Wampole beta-Tec RIA gave serum values 1- to 10-fold higher than those obtained using the Monitor Science beta-hCG system when the same patient or control serum was assayed. Preliminary studies comparing two additional quantitative RIA kits (Serno hCG-beta and Bio-RIA hCG-beta rapid RIA) indicate that the results obtained with the quantitative Wampole and Monitor Science reagents are not peculiar to these two assay systems. Possible explanations of the cause of such aberrant results are presented. It is concluded that variable results can be expected when assaying the same serum sample with different RIA reagents for beta-hCG owing to the lack of an acceptable reference preparation for hCG that can be utilized by all commercial or private producers of such reagents.
D055598:Chemical Phenomena; D002621:Chemistry; D006063:Chorionic Gonadotropin / Q000097:blood*; D006801:Humans; D007202:Indicators and Reagents; D011863:Radioimmunoassay / Q000379:methods*
D006063:Chorionic Gonadotropin; D007202:Indicators and Reagents