Progress toward understanding follicle development in vitro: appearances are not deceiving

Area of Science:

• Reproductive Biology
• Developmental Biology
• Cell Biology

Background:

• Follicle development is complex, influenced by interactive factors determining ovulation or atresia.
• In vitro models are crucial for simplifying and understanding these dynamic processes.
• Current models require refinement to enhance their utility in research.

Purpose of the Study:

• To evaluate the progress of in vitro follicle development models.
• To identify areas needing further consideration for improving model usefulness.
• To compare attached and intact follicle culture approaches.

Main Methods:

• Overview of two primary in vitro follicle culture approaches: attached and intact 3D culture.
• Attached culture involves enzyme-digested or mechanically harvested follicles adhering to a surface.
• Intact follicle culture utilizes mechanically dissected, free-floating preantral follicles.

Main Results:

• Intact follicle culture more closely emulates in vivo development compared to non-intact structures.
• Intact follicle culture facilitates investigation of hormonal and paracrine factor interactions in isolation.
• Studies are exploring local effects of steroids, inhibin, activin, follistatin, and gonadotrophins.

Conclusions:

• Intact follicle culture offers a favorable model for studying isolated follicle development.
• Standardization of in vitro follicle culture conditions is urgently needed for future research.
• Further investigation into gonadotrophin roles, particularly FSH isoforms, is ongoing.