Immunophenotypical Characterization of Limbal Mesenchymal Stromal Cell Subsets during In Vitro Expansion

Area of Science:

• Ophthalmology
• Regenerative Medicine
• Cell Biology

Background:

• Limbal mesenchymal stromal cells (LMSCs) are vital for corneal integrity and regeneration.
• Limited understanding exists regarding LMSC subpopulations and their specific roles.
• Mesenchymal stem/stromal cells (MSCs) are utilized in regenerative therapies, highlighting the potential of LMSCs.

Purpose of the Study:

• To characterize human LMSC subpopulations and their surface markers.
• To investigate the impact of in vitro expansion on LMSC characteristics.
• To elucidate the potential roles of LMSCs in ocular surface repair and regeneration.

Main Methods:

• Flow cytometry was used to assess fifteen cell surface markers in primary LMSCs.
• LMSCs were derived from human corneal transplant remnants.
• Cells were passaged eight times to observe subculture-dependent changes.

Main Results:

• Consistent expression of typical MSC markers was observed.
• Distinct LMSC subpopulations showed passage-dependent expression of wound healing, immune regulation, and differentiation markers.
• High CD166, CD248, CD29, and sustained CD201 expression indicated roles in ocular repair, immunomodulation, and differentiation potential.
• VEGF expression in LMSCs was higher than in fibroblasts and endothelial cells, suggesting roles in angiogenesis and inflammation modulation.

Conclusions:

• Human LMSC subpopulations display significant heterogeneity and multipotent potential during in vitro expansion.
• Specific markers (CD166, CD248, CD29, PEDF, CD201, VEGFR2) highlight LMSCs' roles in ocular surface repair, immunomodulation, and differentiation.
• Findings support the development of standardized protocols for LMSC-based regenerative therapies for ocular surface disorders.