Research On Vascularization Of The VEGF And Collagen Ⅰ Modified β-tricalcium Phosphate Porous Scaffold

Objective: To objective the angiogenesis and osteogenesis of the VEGF and collagenI modified β-tricalcium phosphate porous scaffold in guinea pig’ s otocyst and do apreliminary exploration in search of better composite materials of ossicular prosthesis.Methods: Totally60guinea pigs were randomly divided into experimental group(implant the VEGF and collagen I modified β-tricalcium phosphate porousscaffold),collagen I control group（implant the collagen I modified β-tricalciumphosphate porous scaffold）and blank control group. The guinea pigs were executedunder anesthesia at week1,2,3,4respectively. The surface of scaffolds wereobserved by scanning electron microscopy. The angiogenesis of scaffolds wereobserved by hematoxylin-eosin staining and CD34immunohistochemistry staining,then count the microvascular density. The osteogenesis of the scaffolds were observedby toluidine blue staining.Results: Endothelial cells proliferation and lumen formation can be observed after1week in each group. The density of endothelial cells increases in each group after2weeks, the sprouting of new blood vessels in the pores can be observed inexperimental group，a lot of endothelial cells, fibroblast cells and tubes can beobserved in the other two control groups. The angiogenesis reach the peak after3weeks. However, the vascularization begin to decline after4weeks in each group. The microvascular density of experimental group is more than the other two groups(P>0.05), There was no significant difference between collagen I control group andblank control group. The adherence and proliferation of cells could be examined in thesurface and pores of the scaffold by scanning electron microscope. The osteogenesiscould be observed after4weeks by toluidine blue staining, especially in experimentalgroup.Conclusion:(1) It demonstrated that the VEGF and collagen I modified β-tricalcium phosphateporous scaffold have good biocompatibility and get an effective vascularization in theenvironment of guinea pigs’ middle ear. What’s more, the scaffold also can promotebone formation when compared with the β-TCP porous scaffolds that without VEGF.(2) This research provides a new experimental basis for vascularization in vivo ofporous biological ceramic in tissue engineering. In addition, this research makes apreliminary exploration in search of better composite materials of ossicular prosthesisand provides experimental basis and research foundation.