ACTIVIN-B - DETECTION BY AN IMMUNOENZYMOMETRIC ASSAY IN HUMAN SERUM DURING OVARIAN STIMULATION AND LATE PREGNANCY

A recently developed immunoenzymometric assay for activin B has been c haracterized further by measurement during ovarian stimulation and pre gnancy. The assay is based on a monoclonal anti-peptide antibody, anti -beta(B(101-115)). In addition to quantitative analyses, the antibody has been used for immunohistochemical localization of the activin beta B-subunit in human term placenta. Serum samples obtained from patient s suffering from tubal factor infertility who were admitted for in-vit ro fertilization (IVF) treatment protocols or from patients with prove n fertility who were admitted for laparoscopic tubal ligation were col lected. The aim was to correlate serum activin B concentrations with o ther parameters during IVF and with phases of the menstrual cycle, Ser um samples obtained from healthy pregnant volunteers were studied to c orrelate activin B concentrations with clinical parameters. During the IVF treatment protocols, activin B was detectable in all patients stu died, and a significant negative correlation was observed between seru m activin B and oestradiol concentrations. On the other hand, no signi ficant difference was observed in activin B concentrations when serum samples obtained from patients at different phases of the menstrual cy cle were compared, and low concentrations of activin B were observed i n the samples obtained from these patients. During pregnancy, a positi ve correlation was observed between serum activin B concentrations and gestational age, In immunohistochemical analyses of human placental t issue obtained from healthy parturients, the activin PB-subunit was pr esent in trophoblast, amniotic epithelial and Hofbauer cells. The resu lts suggest a potential clinical application in female reproductive me dicine for serum activin B measurements.