CTGF-Primed Wharton’s Jelly Mesenchymal Stem Cells Enhance Collagen Expression for Soft Tissue Regeneration

Background: Connective Tissue Growth Factor (CTGF) is a matricellular protein implicated in modulating mesenchymal stem cell (MSC) behaviour and extracellular matrix remodelling. This study investigated the dose-dependent effects of CTGF, in the presence or absence of Vitamin C, on Wharton’s Jelly-derived MSCs (WJ-MSCs) with respect to morphology, immunophenotype, collagen gene expression, and protein secretion. Methods: WJ-MSCs were expanded in vitro and treated with CTGF (0–120 ng/mL) and/or 0.5 mM Vitamin C. Morphological changes were evaluated by light microscopy, while flow cytometry was used to analyze surface marker expression (CD73, CD90, and CD105). Collagen gene expression (Col1a1 and Col3a1) was quantified by RT-qPCR, and protein secretion was measured with ELISA. Results: CTGF-treated WJ-MSCs maintained a spindle-shaped morphology and confluent monolayer organization. CD73 expression remained stable at high levels, whereas CD90 and CD105 expression was modulated in a dose-dependent manner. Vitamin C alone downregulated CD105, but this was mitigated by CTGF co-treatment. Col1a1 expression and secretion were significantly increased by CTGF at 50 ng/mL, reaching a maximum at 100 ng/mL with reduced inter-experimental variance. Col3a1 expression was decreased following treatment with CTGF at 10 ng/mL, suggesting a shift in collagen subtype balance. ELISA corroborated increased collagen secretion upon CTGF stimulation. Conclusion: CTGF, particularly at 100 ng/mL in combination with Vitamin C, promotes mesenchymal marker expression, stimulates Col1a1 synthesis, and supports an immunoprivileged phenotype in WJ-MSCs. These findings underscore the potential of CTGF for regenerative strategies aimed at extracellular matrix remodelling and targeted cell therapy.