An enzyme-linked immunoassay for pregnancy-associated plasma protein A is described. The assay is sensitive (7·6 IU/1) and precise (overall CV varied between 8·9% and 10·8%). Recovery was 100% over the working range. Parallel behaviour was observed between the International Reference Preparation 78/610 and pregnancy serum, thus allowing calibration of a laboratory standard pool against IRP 78/610.
References
1.
BischofP. Purification and characterization of pregnancy associated plasma protein A (PAPP-A). Arch Gynecol1979; 315–326
2.
HughesGBischofPWilsonGKlopperA. Assay of a placental protein to determine fetal riskBr Med J1980; 280: 671–3
3.
BischofPHaenggeliLSizonenkoMHerrmannW. Radioimmunoassay for the measurement of pregnancy associated plasma protein A (PAPP-A) in humans. Biol Reprod1981; 24: 1076–81
4.
BischofPBruceDCunninghamPKlopperA. Measurement of pregnancy associated plasma protein A (PAPP-A)Clin Chim Acta1979; 95: 243–7
5.
SinosichMJTeisnerBFolkersenJSaundersDMGrudzinskasJG. Radioimmunoassay for pregnancy-associated plasma protein A. Clin Chem1982; 28: 50–3
6.
MacdonaldDJBelfieldASteeleCJMackDS. The quantitation of pregnancy specific B1.-glycoprotein by enzyme linked immunoassay. Clin Chim Acta1979; 94: 41–9
7.
AvrameasSTernynckT. Enzyme-conjugated antibody methods. In: SteinbergerLA, eds. Immunochemistry. Prentice Hall Inc, Englewood Cliffs, New Jersey1974; 122–3
8.
KrickaLCarterTBurtSusannahKennedyJ. Variability in the absorption properties of microtitre plates used as solid supports in enzyme immunoassay. Clin Chem1980; 741–4
9.
PledgerDBelfieldAStrombergP. Pregnancy specific B1. glycoprotein: A comparison of analysis by radioimmunoassay and enzyme linked immunosorbent assay. Observations on patients with malignant teratoma of testis. J Clin Chem Clin Biochem1981; 19: 943–6
10.
BohnHGrudzinskasJGRosenSSeppalaM. Reference preparation for assay of some pregnancy and cancer-associated antigens. Lancet1980; ii: 796
11.
SmithRCooperWThomsonM. Pregnancy associated plasma protein A. A measure of placental ageing. In: KlopperAGenazzaniACrosignaniP, eds. The human placenta: Proteins and hormones, Academic Press, London1980; 109–13
12.
FolkersonJGrudzinskasJGHindersonPTeisnerB. Pregnancy associated plasma protein A: Circulating levels during normal pregnancy. Am J Obstet Gynecol1981; 139: 910–4
