[Immunochemical identification of beta2-globulin in metastases of ovarian tumors]

Antisera were obtained upon immunization of rabbits with the extracts obtained from metastatic tissues of primary ovarian carcinoma into the omentum. Eight antigens were found, which were termed "ovarian-metastatic antigens" (OMA). OMA 1-7 showed cross-reactions with the antigens of one of the normal organs of the adult man: kidneys, spleen, brain. OMA-8 was not identified in the internal organ tissues of the adults and fetuses. Using immunodiffusion method, OMA-8 was revealed in the tissues of metastases of primary ovarian cancer into the omentum in 55% of cases (3-180 mg/l), in 50% of cases it was detected in primary ovarian carcinomas (3-50 mg/l) and in mature placenta (38-40 weeks) (6-12 mg/l). OMA-8 was detected in the chorion (8-20 weeks) and in the amniotic fluid at all periods at the maximum sensitivity of immunodiffusion method (1-2 mg/l). OMA-8 is a beta 2-globulin of protein nature with NW 35 kD, containing alpha- and beta-subunits with MW 18 and 19.5 kD. No carbohydrates, lipids and ferrum were determined in OMA-8. Its physico-chemical and antigenic properties differ from those of the described carcinoembryonic and placental proteins.