In Vitro Modeling of Human Germ Cell Development Using Pluripotent Stem Cells.

Area of Science:

• Reproductive Biology
• Stem Cell Science
• Developmental Biology

Background:

• Mouse models are insufficient for understanding human germ cell development.
• Human pluripotent stem cells (iPSCs) offer a potential model system.
• Challenges exist in directing iPSC differentiation towards specific germ cell types.

Purpose of the Study:

• To develop an efficient protocol for inducing human iPSCs into spermatogonium-like cells (SLCs).
• To establish a platform for studying human germ cell development and male infertility.
• To investigate the recapitulation of germ cell development defects in vitro.

Main Methods:

• Developed a feeder- and xeno-free culture protocol.
• Induced human iPSCs into PLZF+/GPR125+/CD90+ spermatogonium-like cells (SLCs).
• Analyzed gene expression profiles of induced SLCs for key germ cell markers.

Main Results:

• Successfully generated SLCs expressing key germ cell development genes (MVH, DAZL, GFRα1, NANOS3, DMRT1).
• Observed spontaneous meiosis and haploid cell formation in a fraction of SLCs in vitro.
• Demonstrated recapitulation of NANOS3 deficiency and non-obstructive azoospermia patient iPSC line phenotypes.

Conclusions:

• Established a robust feeder- and xeno-free protocol for generating human SLCs from iPSCs.
• Created a valuable in vitro platform for investigating human spermatogenesis and male infertility.
• The protocol effectively models genetic and patient-derived defects in germ cell development.