Endosialin defines human stem Leydig cells with regenerative potential

Area of Science:

• Reproductive Biology
• Stem Cell Research
• Endocrinology

Background:

• Human stem Leydig cells (SLCs) are crucial for testosterone production.
• Previous markers like PDGFRα and NGFR lack specificity, leading to contamination with other cell types.
• A specific marker is needed for accurate SLC isolation and research advancement.

Purpose of the Study:

• To determine if endosialin is a specific marker for human SLCs.
• To assess the in vitro and in vivo differentiation potential of endosialin-positive cells into Leydig cells (LCs).

Main Methods:

• Re-evaluation of PDGFRα and NGFR specificity in human testes.
• Analysis of single-cell sequencing data to identify potential markers.
• Isolation and characterization of endosialin+ cells using flow cytometry.
• In vitro differentiation assays and in vivo xenotransplantation into immunodeficient mice.

Main Results:

• Endosialin is a more specific marker for human SLCs compared to PDGFRα and NGFR.
• Isolated endosialin+ cells demonstrated self-renewal and multipotent differentiation capabilities in vitro.
• These cells differentiated into functional, testosterone-producing LCs in vitro and partially in vivo.
• Transplanted cells localized, proliferated, and differentiated within the murine testes.

Conclusions:

• Endosialin is a specific marker for human SLCs, enabling their purification.
• Human endosialin+ cells possess stem cell properties and can differentiate into functional LCs.
• This finding supports the potential clinical translation of SLC-based therapies for male hypogonadism.