Comparison of the characteristics of human gingival fibroblasts isolated by tissue explants and by enzyme digestion methods

Objective: To compare the characteristics of human gingival fibroblasts (hGFs) obtained by tissue-explant and enzyme-digestion methods. Methods: The hGFs were isolated using tissue explants and enzyme digestion methods and identified by immunocytochemical analysis. Cell-surface molecules were detected by flow cytometry analysis. The colony-forming activity was examined by CFU-F assay. Oil red O staining and alizarin red staining were performed to identify the adipogenic and osteogenic differentiation of hGFs and the differentiation capacity was quantified using spectrophotometric method. Results: Flow cytometry analysis showed that hGFs expressed CD44, CD29, Strol-1, but not CD34 and CD45. Strol-1 was significantly higher in enzyme-digestion hGFs [(14.84±2.00)%] than in tissue-explant hGFs [(6.64±0.95)%] (P<0.05). CFU-F assay showed that the self-renewal capacity of hGFs in enzyme-digestion group [(21±8)%] was significantly higher than that in tissue-explant group [(14±8)%] (P<0.05). The quantification test of adipogenic differentiation capacity showed the absorbance of enzyme-digestion group [0.66±0.03] was much higher than that tissue-explant group [0.45±0.04] (P<0.05). And the similar result was showed in the osteogenic differentiation capacity test that the absorbance of enzyme-digestion group [0.14±0.01] was obviously higher than that tissue-explant group [0.12±0.01] (P<0.05). Conclusions: Compared with tissueexplant hGFs, enzyme-digestion hGFsshowed much more mesenchymal stem cell-like properties with significantly higher self-renewal capacity and adipogenic and osteogenic differentiation ability.