Granulosa Cell Interactions in Ovarian Folliculogenesis

Granulosa cells form the somatic compartment of the ovarian follicle, surrounding and nurturing the developing oocyte through successive stages from primordial to preovulatory follicles. These cells differentiate into cumulus granulosa cells, which lie in intimate contact with the oocyte, and mural granulosa cells, which line the follicular wall and mediate endocrine interactions. Paracrine factors secreted by both oocyte and granulosa cells—including growth differentiation factor 9 (GDF9), bone morphogenetic protein 15 (BMP15) and stem cell factor (SCF)—establish bidirectional signalling networks that regulate granulosa proliferation, steroidogenesis and meiotic maturation. Follicle-stimulating hormone modulates this local milieu, promoting KIT ligand expression and follicle survival, while luteinising hormone triggers granulosa cell luteinisation and ovulation readiness. Disruption of these finely tuned interactions underlies a spectrum of reproductive disorders, and elucidation of the molecular crosstalk offers avenues for therapeutic intervention in infertility and for optimisation of in vitro maturation systems.

Research from Nature Portfolio

Recent studies have examined serum SCF levels immediately prior to ovulation induction and demonstrated that lower SCF concentrations on day 8 of stimulation and on the day of oocyte retrieval correlate with the formation of top-quality blastocysts in women with mild endometriosis. These findings suggest that SCF measurement could serve as a predictive biomarker for embryo developmental competence across diverse ovarian reserve profiles. In a complementary line of investigation, activation-induced cytidine deaminase (AID) has emerged as a novel regulator of oocyte-granulosa cell feedback. Loss of AID in murine models decreases oocyte expression of GDF9 and granulosa cell SCF, indicating a methylation-independent mechanism by which AID sustains the GDF9–SCF paracrine loop essential for follicle growth.

Granulosa Cell Interactions in Ovarian Folliculogenesis publication trend

The graph below shows the total number of articles in granulosa cell interactions in ovarian folliculogenesis across all publications each year (not limited to Nature Index journals).

Technical terms

Granulosa cells: Somatic cells within the follicle that support oocyte development and produce steroid hormones.
Folliculogenesis: The multistage process of ovarian follicle growth, maturation and ovulation.
Cumulus granulosa cells: Subset of granulosa cells that directly envelop the oocyte and mediate nutrient and signal exchange.
Mural granulosa cells: Granulosa cells that line the follicular wall, contribute to steroidogenesis and respond to gonadotrophins.
Paracrine signalling: Local communication between neighbouring cells via secreted factors.
Stem Cell Factor (SCF): Also known as KIT ligand, a growth factor that binds c-Kit receptor to regulate granulosa cell survival and oocyte maturation.
Single-cell RNA-sequencing (scRNA-seq): High-resolution transcriptomic profiling technique that dissects cellular heterogeneity within complex tissues.

References

1. Luteinizing Hormone Receptor Mutation (LHRN316S) Causes Abnormal Follicular Development Revealed by Follicle Single-Cell Analysis and CRISPR/Cas9. Interdisciplinary Sciences: Computational Life Sciences (2024).
2. Serum levels of stem cell factor for predicting embryo quality. Scientific Reports (2024).
3. Activation-induced cytidine deaminase is a possible regulator of cross-talk between oocytes and granulosa cells through GDF-9 and SCF feedback system. Scientific Reports (2021).
4. Effects of stem cell factor in follicular fluid and granulosa cells on oocyte maturity and clinical pregnancy. Medicine (2023).
5. The potential role of the KFG and KITLG proteins in preventing granulosa cell apoptosis in Bubalus bubalis. Journal of Genetic Engineering and Biotechnology (2023).