Abstract: BACKGROUND: Previous studies have shown that composite scaffolds prepared from a certain proportion of gelatin-methacryloyl and treated dentin matrix exhibit excellent biological properties, which are beneficial for cell proliferation and adhesion. Composite biological scaffolds loaded with basic fibroblast growth factor provide a new idea for dental pulp revascularization.
OBJECTIVE: To observe the effect of gelatin-methacryloyl/treated dentin matrix composite biological scaffold loaded with basic fibroblast growth factor on the proliferation, migration, and angiogenic properties of human dental pulp stem cells.
METHODS: Composite biological scaffolds loaded with 0, 50, 100, 200, and 500 ng/mL of basic fibroblast growth factor were prepared. The proliferation ability of dental pulp stem cells was detected by CCK-8 assay and the optimal mass concentration of basic fibroblast growth factor was screened. The dental pulp stem cells were divided into three groups, namely gelatin-methacryloyl/treated dentin matrix group, basic fibroblast growth factor- gelatin-methacryloyl/treated dentin matrix group, and blank control group. The scratch assay was used to detect the migration ability of dental pulp stem cells. Matrigel tubule formation assay was used to detect the number of branch points of dental pulp stem cell tubules. The immunofluorescence staining was used to detect the expression of vascular endothelial growth factor protein in dental pulp stem cells. qPCR was used to detect the expression of angiogenesis-related genes (vascular endothelial growth factor, transforming growth factor β, and ephrin B2) in dental pulp stem cells.
RESULTS AND CONCLUSION: (1) CCK-8 assay showed that the gelatin-methacryloyl/treated dentin matrix composite scaffolds loaded with basic fibroblast growth factor could promote the proliferation of dental pulp stem cells at 3 and 5 days of culture, among which the proliferation-promoting effect of basic fibroblast growth factor (100 ng/mL)- gelatin-methacryloyl/treated dentin matrix composite scaffold was the most obvious. (2) Cell scratch assay showed that the cell migration area of basic fibroblast growth factor (100 ng/mL)-gelatin-methacryloyl/treated dentin matrix composite scaffold group was significantly larger than that of gelatin-methacryloyl/treated dentin matrix group and blank control group. (3) Matrigel tubule formation assay showed that the number of branch points of basic fibroblast growth factor (100 ng/mL)-gelatin-methacryloyl/treated dentin matrix composite scaffold was greater than that of gelatin-methacryloyl/treated dentin matrix and blank control groups. (4) Immunofluorescence assay showed that the average positive absorbance value of vascular endothelial growth factor in basic fibroblast growth factor (100 ng/mL)-gelatin-methacryloyl/treated dentin matrix composite scaffold group was higher than that of gelatin-methacryloyl/treated dentin matrix and blank control groups. (5) qPCR assay showed that the expression of vascular endothelial growth factor, transforming growth factor β, and ephrin B2 in the basic fibroblast growth factor (100 ng/mL)-gelatin-methacryloyl/treated dentin matrix composite scaffold group was higher than that in the gelatin-methacryloyl/treated dentin matrix and blank control groups. The results showed that basic fibroblast growth factor (100 ng/mL)-gelatin-methacryloyl/treated dentin matrix composite scaffold exhibited good ability to promote the proliferation, migration, and angiogenesis of dental pulp stem cells.

Key words: human dental pulp stem cell, alkaline fibroblast growth factor, cell proliferation, composite bioscaffold, angiogenesis, tissue engineering