Purification, Characterization and Pharmacokinetic Study of a Novel Long-acting Follicle-stimulating Hormone

Abstract

Follicle-stimulating hormone( FSH) has been utilized to treat male and female infertility. However,frequent injection of FSH to patients is required due to its short serum half-life. Developing a longacting recombinant FSH is clinically desirable. A DNA construct containing FSH-CTP-vFc was made by fusing the coding sequence of carboxyl-terminal peptide( CTP) of the β-subunit of human chorionic gonadotropin and a variant of human Immunoglobulin G2( IgG2) Fc fragment( vFc) into FSH gene. The DNA construct was transfected into Chinese Hamster Ovary( CHO) cells,and cell clones with highly and stably expressed FSHCTP-vFc fusion protein were selected. The cultured medium of cell was collected for protein purification by protein A based chromatography. Biochemical and physical characterization were performed for the fusion proteins purified from the samples of different culture time. ELISA assay and animal study shows that the purified FSHCTP-vFc protein has significant activity in vitro and in vivo. Pharmacokinetic research demonstrates that the serum half-life of the fusion protein is almost ten fold of the recombinant FSH's. Obviously,this novel long-acting FSHCTP-vFc protein could greatly reduce the injection frequency and improve the patient compliance.