Characterization of the human fetal rete region by single cell transcriptional analysis of gonads and mesonephros/epididymis

TAELMAN, J.; CZUKIEWSKA, S. M.; MOUSTAKAS, I.; CHANG, Y. W.; HILLENIUS, S.; van der HELM, T.; MEI, H.; FAN, X.; Chuva de Sousa Lopes, S. M.

doi:10.1101/2022.07.20.500903

bioRxiv · 10.1101/2022.07.20.500903

Characterization of the human fetal rete region by single cell transcriptional analysis of gonads and mesonephros/epididymis

TAELMAN, J.·CZUKIEWSKA, S. M.·MOUSTAKAS, I.·CHANG, Y. W.·HILLENIUS, S.·van der HELM, T.·MEI, H.·FAN, X.·Chuva de Sousa Lopes, S. M.

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Abstract

During development of the male reproductive tract, the human rete functions as a bridging structure between the seminiferous tubes and the efferent ducts of the epididymis. However, despite its significant contribution to human sex-specific gonadogenesis and future male fertility, the rete testis remains poorly understood. To investigate fetal rete testis development, we have performed single-cell transcriptomics on human fetal testes (and ovaries) and mesonephros/epididymis from first and second trimester. By revealing KRT19 and PAX8 as rete markers, we were able to identify the molecular signatures of the rete epithelial cells and mesonephros/epididymis epithelial cells. In the process, we have identified a population of Sertoli cells and germ cells in the rete testis. Moreover, we also revealed a small population of epithelial cells in the rete ovarii, comparable to the epithelial cells in the rete testis. Together, our study provides insights into human fetal sex-specific gonadogenesis and development of the male reproductive tract beyond the gonads.

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TAELMAN, J., CZUKIEWSKA, S. M., MOUSTAKAS, I., CHANG, Y. W., HILLENIUS, S., van der HELM, T., MEI, H., FAN, X., Chuva de Sousa Lopes, S. M.. 2022-07-22. Characterization of the human fetal rete region by single cell transcriptional analysis of gonads and mesonephros/epididymis. https://doi.org/10.1101/2022.07.20.500903

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