ESPE Abstracts

Background: Determination of the gonads in men is closely dependent on Sertoli cells differentiation and maturation. Many cases of differences of sex development (DSD) are caused by variations in these processes. The study of the mechanisms underlying these complex conditions is crucial for optimal clinical management and Sertoli cells would be an ideal model for this purpose. Our human Sertoli-like cell model (SLCs) may shed some light on the identification of new genes and common pathways involved in the mechanism of disease in DSD.

Objective and Hypothesis: To explore the transcriptomes of three Sertoli cell models Ntera2 (NT2d1), primary human Sertoli cells (HSerCs) and the new SLCs in order to find significant expression differences and similarities that prove the quality of SLCs as a human Sertoli cell model and highlight new potential genes involved in the development of human Sertoli cells.

Methods: We used RNA-Sequencing to analyze the transcriptome of NT2d1, HSerCs and SLCs. Gene Ontology (GO) enrichment of the significantly regulated genes (P<0.05, FC>=2) in NT2/D1, HSerC and SLCs, compared to induced pluripotential stem cells (iPSCs) using ToppCluster. Similarities and differences in the transcriptome of the three Sertoli-like cell lines were visualized using Cytoscape.

Results: This approach revealed that SLCs and HSerCs are much more similar among each other (37 upregulated genes in common) than NT2d1 cells (only 3 upregulated genes in common). We observed that SLCs and HSerCs significantly expressed PAX2 and Hox gene complex from the Homeobox family, a renowned sub-family of genes expressed in both fetal and adult reproductive organs. Both Pax2 and Hox genes are linked to multiple steps of urogenital development and bipotential gonad formation. The functional redundancy among members of this large family may be masking a role in sex developmental defects. Of special interest is the observed significant upregulation of TBX18, (member of the T-box family), with some members of this family forming a complex with HOX proteins to initiate Sf1 gene expression during adrenal development.

Conclusion: Sertoli-like cells have proved to be a better model than the commonly used NT2d1 cells to study human Sertoli cells. Moreover, the comparison of high-quality Sertoli cell models highlighted several common genes that may conceal a not yet known role in male gonadal development.