In-vitro biopotency and glycoform distribution of recombinant human follicle stimulating hormone (Org 32489), Metrodin and Metrodin-HP

In this study the in-vitro biopotency and glycoform distribution of human recombinant follicle stimulating hormone (FSH, Org 32489) has been assessed. The biopotency of recombinant FSH was studied using animal (rat Sertoli) and human (granulosa-lutein) cell models. Recombinant FSH, as measured in the rat Sertoli cell assay, was more potent than the urinary preparations Metrodin, Metrodin-HP and IS 70/45 with half maximal stimulation (ED50; mean ± SEM, n 3) occurring at 2.2 ± 0.5 IU/I (recombinant FSH), 4.7 ± 1.1 IU/I (Metrodin), 13.2 ± 0.7 IU/I (Metrodin-HP) and 6.4 ± 0.3 IU/I (IS 70/45); the pituitary preparation IRP 83/575 had an EDM of 10.4 ± 0.1 IU/I. Using human granulosa-lutein cells, cultured for up to 4 days in the absence of exogenous steroid precursors, recombinant FSH was either without effect (three out of five patients) or inhibited both oestradiol and progesterone secretion. FSH (83/575) was without effect on oestradiol with preparations from any of the patients but slightly stimulated (134 ± 8%; mean ± SEM, P < 0.05) progesterone production at the highest dose (80 IU/I). The distribution of FSH isoforms, assessed by polyclonal radioimmunoassay, following chromatofocusing over the ranges pH < 3.5 and pH 3.5–7.0 respectively was recombinant FSH, 12.4 and 87.6%; Metrodin, 19.8 and 80.2%; Metrodin-HP, 50.2 and 49.8%; IS 70/45, 15.0 and 85.0%; IS 83/575, 70.9 and 29.1%. All glycoforms were pi