Objective: To investigate the distribution and content of transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor (VEGF) in concentrated growth factors (CGF) gel, and to clarify the difference among different layers of CGF.
Methods: Venous blood samples were collected from 6 healthy volunteers to prepare CGF. The distribution, integrated optical density (IOD) and average optical density (AOD) of TGF-β1 and VEGF in CGF gel and red blood cell (RBC) layer were measured using immunohistochemistry. The concentrations of TGF-β1 and VEGF in the supernatant serum at baseline and the CGF releasate after 1 day were evaluated with enzyme-linked immunosorbent assays.
Results: Abundant TGF-β1 and VEGF were concentrated in CGF gel. However, only a little could be found in polykaryocytes and sporadic platelets in RBC layer. Platelets and leukocytes were concentrated in between the two layers with high expression of TGF-β1. The concentrations of TGF-β1 and VEGF in the CGF releasate(55 236.78±3 686.34), (610.99±148.81) ng/L were significantly higher than those in the supernatant serum (20 710.20±4 523.14), (335.20±51.69) ng/L (P<0.001).
Conclusion: CGF contains high quantities of TGF-β1 that can promote new bone formation and tissue healing. We suggest that CGF gel should be used right after being prepared. Supernatant serum and the area between CGF gel and RBC layer could also be mixed with bone substitute materials.