Development of a radioimmunoassay for pregnancy‐specific beta₁‐globulin and its measurement in serum of patients with trophoblastic and non‐trophoblastic tumours

Abstract

Levels of human pregnancy-specific or trophoblast-specific beta1-globulin (TBG) were measured by double-antibody radioimmunoassay (RIA) in 103 patients with trophoblastic tumours and in 114 patients with a variety of non-trophoblastic tumours. The sensitivity of RIA for TBG was about 1 ng per ml. Twenty healthy adult females and males had levels below 1 ng per ml. Using the RIA for measurement of TBG in sera which were selected from immunodiffusion-TBG-negative samples, we detected elevated TBG levels in 76.7% of cases with trophoblastic tumours and in 15% of different cases with non-trophoblastic malignancies. The diagnostic and prognostic significance of the measurement of TBG levels by RIA in patients with trophoblastic tumours is discussed.

The diagnostic value of circulating trophoblast-specific β1-glycoprotein (TSG) in cancer patients

“…Subsequently, TSG was discovered in the serum of patients with trophoblastic (Tatarinov et al, 1974) and testicular tumours (Tatarinov et al, 1975;Johnson et al, 1977) and in non-trophoblastic malignancies (Horne et al, 1976;Tatarinov & Sokolov, 1977) and the frequency of raised levels of TSG was compared with HCCG in these tumour groups Seppala et al, 1978;Searle et al, 1978;Tatarinov et al, 1976;Johnson et al, 1977;Wuirz et al, 1979).…”

“…Sera radioimmunoassay as described previously (Tatarinov & Sokolov, 1977). The sensitivity of the double-antibody radioimmunoassay for TSG was -1 ng/ml; the lowest measurable serum level of TSG was 3 ng/ml.…”

“…TSG was labelled with 1251 (Tatarinov & Sokolov, 1977). 041 ml of 01M phosphate-buffered saline (PBS, pH 7-6) containing 30 Hug of TSG was added to 0-1 ml of PBS containing 041 mg of chloramine-T and 2 mCi carrier-free Na1 251 with a specific activity of 106 mCi/ml (Leningrad, I)epartment of 13iocliemistry, 2nd i\Ioscowr MIedical tubes were incubated at 4°C for 24 h in a Rotamixer.…”

“…For the assay, reagents were addied in the following order: (1) 0.15 ml anti-TSG appropriately diluted: e.g. 1:32,000; (2) 0 05 ml 1251-TSG dilution containing 32,000 ct/min; (3) 0*05 ml of test serum sample or standard TSG; (4) After 16 h of incubation at 20°C, 041 ml of immunoadsorbant containing anti-RGG was added and left to stand for 4 h in the The methods of immunoelectrophoresis in agar, disc-electrophoresis, double immunodiffusion in agar with standard test system and immunoradioautography for identification and titration of TSG, have been reported in previous publications (Tatarinov & Masyukevich, 1970;Tatarinov & Sokolov, 1977).…”

Radioimmunoassay of SP1(Pregnancy-specificβ1-glycoprotein) in maternal blood and in amniotic fluid in normal and pathologic pregnancies

“…SPj was isolated and characterized by BOHN [l, 2]. TATARINOV reported on comparative immunodiffusion investigations which showed identity of his pregnancy specific ß-globulin [20,21] andof PAPP-C of LIN et al [9] with pregnancy-specific ßi -glycoprotein (SPi). SPj was characterized äs a ß l -glycoprotein with a carbohydrate content of 29% and a molecular weight of 90000-110000 [3,9].…”