Immunoradiometrical Measurement of Tissue Polypeptide Specific Antigen (TPS) in Normal, Healthy, Nonpregnant and Pregnant Japanese Women

Abstract

Using a monoclonal immunoradiometrical assay, we measured the concentrations of the specific epitope M3 of tissue polypeptide antigen (TPA), namely, tissue polypeptide specific antigen (TPS), in serum and amniotic fluid obtained from normal, healthy, nonpregnant and pregnant Japanese women (NHNJW and NHPJW). The cut-off value of the serum TPS level was set at 130 U/l, based on the mean +2 standard deviations in the NHNJW. The serial measurement of serum TPS levels demonstrated the significant temporal elevation of TPS level near the time of ovulation (+/- 3 days) in the ovulatory women. In the NHPJW, the mean serum TPS level and the positivity rate (> 130 U/l) increased with the advance of gestation, reaching 183.7 U/l and 66.7%, respectively, in the third trimester. Maternal serum levels were much elevated just before (mean: 982.3 U/l) and after (mean: 824.6 U/l) delivery, and were reduced to about one-fourth by 3 days. In addition, markedly high TPS concentrations were found in the retroplacental blood (one case: 9,076 U/l) and the amniotic fluid (mean: 11,650 U/l). The serum TPS level correlated well (r = 0.871) with the serum TPA level in the TPS range of 2-2,000 U/l, while a poor correlation (r = 0.273) was found in the TPS range of 2-500 U/l. The present study thus obtained fundamental data on TPS in Japanese women. The fluctuation and change of serum TPS levels during the menstrual cycle and in pregnancy should be taken into consideration when we apply TPS as a tumor marker for women.