Objective: To determine the effect of insulin-like growth factor-II (IGF-II) on human granulosa cell proliferation in vitro.
Design: Thymidine incorporation and cell count were determined to assess human granulosa cell proliferation.
Setting: The study was performed in an academic research environment.
Patients: Granulosa cells were obtained from women undergoing IVF procedures.
Interventions: Granulosa cells were dispersed enzymatically and cultured in both serum-containing and serum-free medium.
Main outcome measure: Granulosa cell proliferation in basal conditions and after stimulation with IGF-II given alone or in combination with basic fibroblast growth factor (basic FGF).
Results: Treatment of human granulosa cells with IGF-II for 24 hours significantly increased thymidine incorporation. Furthermore, this mitogenic effect was confirmed when granulosa cells were cultured in presence of IGF-II for 7 to 10 days and their proliferation was evaluated by cell counting. The association of IGF-II and basic FGF did not result in a synergistic or additive effect.
Conclusion: As already demonstrated in other species, IGF-II also is able to stimulate human granulosa cell proliferation in vitro. Thus, it might be considered among the intraovarian modulators of granulosa cell physiology.