A perivascular origin for mesenchymal stem cells in multiple human organs

Area of Science:

• Cell Biology
• Regenerative Medicine
• Stem Cell Research

Background:

• Mesenchymal stem cells (MSCs) are crucial multipotent progenitor cells with poorly understood origins and native locations.
• Identifying the native source of MSCs is vital for understanding their role in tissue repair and development.

Purpose of the Study:

• To prospectively identify and characterize the native cell population responsible for mesenchymal stem cell (MSC) characteristics.
• To investigate the potential of these identified cells to differentiate into various cell types and their role in tissue regeneration.

Main Methods:

• Prospective isolation of perivascular cells from human skeletal muscle, pancreas, adipose tissue, and placenta using specific cell surface markers (CD146, NG2, PDGF-Rbeta).
• Assessment of myogenic potential in vitro and in vivo, and evaluation of osteogenic, chondrogenic, and adipogenic differentiation capacities at clonal levels.
• Analysis of MSC marker expression on both cultured and native perivascular cells, alongside chemotaxis migration studies.

Main Results:

• Perivascular cells, primarily pericytes, were identified in multiple human organs and expressed key MSC markers.
• Purified perivascular cells demonstrated robust myogenic potential in culture and in vivo, irrespective of tissue origin.
• Long-term cultured perivascular cells retained multipotency, exhibiting osteogenic, chondrogenic, and adipogenic differentiation, and showed chemotactic migration.

Conclusions:

• Blood vessel walls contain a reserve of progenitor cells, likely pericytes, that serve as the origin of mesenchymal stem cells (MSCs).
• These perivascular progenitor cells possess multipotent differentiation capabilities and are integral to the understanding of MSCs and related adult stem cells.