[Basic studies of BALL ELSA CA125-II KIT for detection of serum cancer antigen 125]

We made basic studies of BALL ELSA CA125-II KIT which is a solid phase two site immunoradiometric assay. The first monoclonal antibody (M11) is coated on the BALL ELSA solid phase, and the second one (OC125), radiolabeled with 125I, is used as a tracer. Since serum CA125 values varied by incubation time, incubation temperature and agitation speed, the conditions of the assay had to be kept strictly. Intra- and interassay reproducibility, recovery test and dilution test were well satisfied. Prozone phenomenon was observed over 5,000 U/ml. The minimum detectable concentration was 7.5 U/ml. Serum CA125 values measured using BALL ELSA CA125-II KIT was correlated with those measured using conventional CENTOCOR CA125 RIA KIT (y = 1.058x-0.106 r = 0.973), although in the serum of a patient with chronic pancreatitis the discrepancy between serum CA125 values measured using these kits was observed.