Comparative Analysis of the Effect of Gene-Activated Grafts Carrying a PBUD-VEGF165A-BMP2 Plasmid on Bone Regeneration in a Rat Femur Defect Model

Delayed union and non-union are widespread complications of bone fracture healing which are worse in cases of concomitant chronic diseases (diabetes mellitus, alcoholism, etc.). Osteonecrosis of different etiology is another cause of persistent bone defects. In the current research, we tested gene-activated grafts (GAGs) carrying dual expression cassette plasmid constructs encoding human vascular endothelial growth factor A (VEGF-A) and bone morphogenetic protein 2 (BMP2) genes. We modeled a thighbone diaphyseal defect on male Wistar rats and tested either GAG based on collagen and hydroxyapatite granules (Collapol CP-3) or GAG octacalcium phosphate (OCP) grafts. Histological examination revealed significant increases in vascularization and bone tissue formation in the GAG Collapol CP-3 graft experimental group, while neither the OCP nor the GAG OCP group showed a positive effect on callus formation. We conclude that GAG Collapol CP-3 bone grafts are a potential therapeutic solution for bone tissue regeneration and further clinical studies are required.