Co-culture induces expression of female primordial germ cell-specific genes in human Wharton's jelly-derived mesenchymal stem cells

Am J Transl Res. 2022 Dec 15;14(12):8828-8842. eCollection 2022.

Abstract

Objective: To detect mRNA and protein expression of meiosis-specific genes in human umbilical cord mesenchymal stem cells (hUMSCs) in an in vitro co-culture microenvironment with mouse primordial germ cells (PGCs), and to further explore the effective potential of hUMSCs to differentiate into PGCs.

Methods: HUMSCs were obtained from human Wharton's jelly fragments by adherent culture. PGCs were derived from 12.5 days post-coitum (dpc) BalbC mice. Then hUMSCs were co-cultured with PGCs in Matrigel, inside or outside of a culture chamber, respectively. The changes in morphology and cytogenetic characteristics were observed. SCP3 and DDX4 expression in hUMSCs were detected and analyzed using immunofluorescence staining. Oct-4, Stra8, Zp3 and Dmc1 gene expressions in PGCs, hUMSCs, and hUMSCs after co-culture with PGCs were analyzed by real time reverse transcription-polymerase chain reaction.

Results: Both hUMSCs and PGCs expressed Oct-4 at different degrees. After co-culture with PGCs, hUMSCs became rounded and showed AKP activity. HUMSCs suspension-cultured in Matrigel or adherent cultured with cell chamber significantly expressed Stra8, DMC1, SCP3 and DDX4 genes.

Conclusion: HUMSCs can be induced to express PGC-specific genes Stra8 and DMC1, spermatogonium/oogonium-specific genes SCP3 and DDX4 that predict directed differentiation potential into early germ cells at a molecular level.

Keywords: Human umbilical cord mesenchymal stem cells; induced differentiation; primordial germ cells; specific gene expression.