Gingival epithelial cell-derived microvesicles activate mineralization in gingival fibroblasts

Area of Science:

• Oral biology
• Cell biology
• Biomineralization

Background:

• Soft tissue calcification is a widespread phenomenon affecting various body parts, including gingival tissues.
• The function of microvesicles (MVs) derived from epithelial cells in regulating fibroblast mineralization remains largely unexplored.

Purpose of the Study:

• To investigate the hypothesis that microvesicles (MVs) derived from gingival epithelial cells can regulate the calcification of gingival fibroblast cultures within an osteogenic environment.

Main Methods:

• Human gingival fibroblasts (HGFs) were cultured in an osteogenic differentiation medium.
• Cultures were stimulated with or without human gingival epithelial cell-derived MVs.
• Mineralization, MV localization, mineral deposit assessment, and gene expression profiling (including real-time qPCR) were performed.

Main Results:

• Epithelial MVs robustly stimulated HGF mineralization within one week, with further enhancement by four weeks.
• MVs were internalized by HGFs, inducing intracellular mineral accumulation without calcifying the MVs themselves.
• Gene expression analysis revealed an initial increase in inflammation-related genes, followed by significant upregulation of OSX, BSP, and MMPs in later cultures.

Conclusions:

• Gingival epithelial cell-derived MVs play a significant role in promoting the mineralization of gingival fibroblasts.
• These MVs induce intracellular mineral deposition and modulate gene expression profiles in fibroblasts.
• The findings suggest a novel association between epithelial cells and the pathogenesis of ectopic mineralization in soft tissues.