CD146 expression on mesenchymal stem cells is associated with their vascular smooth muscle commitment

Area of Science:

• Stem cell biology
• Cellular and Molecular Medicine

Background:

• Mesenchymal stem cells (MSCs) are multipotent progenitors with diverse functions.
• Heterogeneity within MSC populations affects their differentiation and proliferation capacities.
• CD146 expression is a marker with variable presence in MSCs.

Purpose of the Study:

• To investigate the functional implications of CD146 expression heterogeneity in bone marrow MSCs.
• To determine if CD146 expression levels correlate with specific MSC functions and lineage commitment.

Main Methods:

• Comparison of CD146(-/Low) and CD146(High) MSC subpopulations.
• Analysis under clonal conditions and after cell sorting.
• Assessment of proliferation, differentiation potential (osteogenic, adipogenic, chondrogenic), and hematopoietic support.
• Evaluation of vascular smooth muscle cell (VSMC) lineage commitment markers.

Main Results:

• No significant differences in colony-forming unit-fibroblast number, differentiation potential, or hematopoietic support between CD146 subsets.
• CD146(-/Low) clones showed slightly faster proliferation than CD146(High) clones.
• High CD146 expression correlated with VSMC lineage commitment, indicated by increased calponin-1 and SM22α expression and collagen matrix contraction.

Conclusions:

• CD146 expression heterogeneity defines functional subpopulations within bone marrow MSCs.
• High CD146 expression marks a subpopulation committed to a vascular smooth muscle cell lineage.
• This finding aids in understanding MSC heterogeneity and potential therapeutic applications.