Construction and expression of vectors encoding biologically active rodent gonadotropins

Area of Science:

• Reproductive endocrinology
• Molecular biology
• Biotechnology

Background:

• Gonadotropins, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), are crucial for vertebrate reproduction.
• Pituitary gland isolation of gonadotropins suffers from cross-contamination, affecting activity measurements.
• Recombinant hormone production offers a solution to improve purity and consistency.

Purpose of the Study:

• To express recombinant rat, mouse, and mastomys FSH and LH in Chinese hamster ovary (CHO) cells.
• To confirm the production and biological activity of these recombinant rodent gonadotropins.

Main Methods:

• Co-expression of common α-subunits and hormone-specific β-subunits in a single mammalian expression vector.
• Utilizing Chinese hamster ovary (CHO) cells for recombinant protein production.
• Immunohistochemistry to confirm the presence of dimeric hormone subunits.
• In vitro bioassays to assess hormonal activity (estradiol and testosterone production).

Main Results:

• Follicle-stimulating hormone (FSH) was successfully expressed from all three rodent species (rat, mouse, mastomys).
• Mouse luteinizing hormone (LH) was expressed, but rat and mastomys LH expression was not achieved.
• Immunohistochemistry confirmed the assembly of dimeric gonadotropins in CHO cells.
• Recombinant FSH stimulated estradiol production in granulosa cells, and recombinant LH stimulated testosterone production in Leydig cells, confirming biological activity.

Conclusions:

• Recombinant expression of rodent gonadotropins in CHO cells is a viable method for producing biologically active hormones.
• This approach overcomes limitations associated with pituitary-derived gonadotropins.
• Further development could enable the production of other species' LH and improve recombinant hormone therapies.