[Immunochemical identification of onco-ovarian acid-soluble alpha-2-globulin]

Antisera were obtained by rabbits immunization with pooled extract from ovarian carcinoma and its metastases into the ome tum. Using standard test-system antigen, precipitating in agar, was identified in the tissue of 12 out of 24 primary ovarian carcinomas and in 8 out of 20 metastases. It was not revealed in adult healthy internal organs tissues and in fetal tissues, except embryonal large intestine, where it was determined in trace amounts in isolated samples. Using immunodiffusion method it wasn't determined in blood serum of healthy people and patients, pregnant women and neonates. Immunochemical identification using standard test-systems showed that this antigen is not identical with already known carcino-embryonic antigen, placental, reactive and onco-ovarian proteins. It presents acid-soluble alpha-2-globulin (ASAG-2) with MW 55 kD determined by gel-filtration and 55 kD determined by electrophoresis in 10% polyacrylamide gel with dodecylsulfate under reducing conditions. Physico-chemical and antigenic properties of ASAG-2, as we think, give the opportunity to present it as a new onco-ovarian antigen, which differs from the known proteins.