Expression of human choriogonadotropin in monkey cells using a single simian virus 40 vector

We have inserted the cDNAs coding for both polypeptide subunits, alpha and beta, of human choriogonadotropin (hCG) into a single simian virus 40 expression vector in such a way that they replace the viral VP2 and VP1 coding sequences, respectively. Monkey cells infected with this virus and the appropriate helper virus produce dimeric hCG. hCG produced in this system was shown to chromatograph identically to standard hCG preparations on gel filtration and to be biologically active in the mouse uterine weight assay.