Angiogenesis induced by autologous whole bone marrow stem cells seeded on collagen scaffolds in silicone nerve tubes. An experimental study

Objective: This study aimed at evaluating Vascularity of tissues formed in silicone nerve tubes with collagen scaffolds seeded with Bone marrow stem cells (BMSC) as a sign of tissue regeneration. Materials and methods: Six adult mongrel dogs were included in this study; a 3 cm gap was made on the buccal branch of right side of facial nerve and also on the left side as a “control side”. Next mononuclear cells containing mesenchymal stem cells were separated from whole bone marrow using Gradient separation method with Ficoll. Silicone tubes embedded with collagen type I sponge seeded with stem cells and neurogenic media were sutured in the perineural fascia of both ends of the cut nerve on the experimental side, while in the control side empty silicone tubes alone were sutured to the perineural fascia of the cut nerves. Healing was evaluated at 8 and 10 weeks scarifying 3 dogs each time and performing histological analysis. Results: After 8 weeks the 6 dogs showed limited movement in the facial area supplied by the buccal nerve on the experimental side and the salivary drooling decreased moderately. After 10 weeks the remaining dogs showed observable muscle movements and decreased salivary drooling in contrast to control side. These results go with the histological examination results showing massive multiple blood vessels formation and nerve like structures with partial absorption of the scaffold at 8 weeks then well organized nerve like tissues with dilated multiple blood vessels at 10 weeks. Conclusion: Collagen scaffolds seeded with mononuclear layer containing stem cells and nerve growth factors showed efficacy at achieving good neo-vascularization which lead to eventual good healing.