Immortalization of epidural fat-derived mesenchymal stem cells: characterization and adipocyte differentiation potential.

Background: Mesenchymal stem cells (MSCs) are promising candidates for regenerative therapy due to their self-renewal capability, multilineage differentiation potential, and immunomodulatory effects. The molecular characteristics of MSCs are influenced by their location. Recently, epidural fat (EF) and EF-derived MSCs (EF-MSCs) have garnered attention due to their potential benefits to the spinal microenvironment and their high expression of neural SC markers. However, their clinical applications are limited due to cell senescence and limited accessibility of EF. Although many studies have attempted to establish an immortalized, stable SC line, the characteristics of immortalized EF-MSCs remain to be clarified.

Aim: To establish and analyze stable immortalized EF-MSCs.

Methods: The phenotypes of EF-MSCs were analyzed using optical microscopy. Cell immortalization was performed using lentiviral vectors. The biomolecular characteristics of the cells were analyzed by immunoblotting, quantitative PCR, and proteomics.

Results: The immortalized EF-MSCs demonstrated a significantly extended lifespan compared to the control group, with well-preserved adipogenic potential and SC surface marker expression. Introduction of human telomerase reverse transcriptase genes markedly increased the lifespan of EF-MSCs. Proteomics analysis revealed substantial increase in the expression of DNA replication pathway components in immortalized EF-MSCs.

Conclusion: Immortalized EF-MSCs exhibited significantly enhanced proliferative capacity, retained adipogenic potential, and upregulated the expression of DNA replication pathway components.