VEGF Encapsulation Through a Novel Microfluidic Technique for Bone Tissue Regeneration and Repair
Lobat Tayebi is an Associate Professor and Director of Research at Marquette University School of Dentistry. She received her PhD from University of California-Davis in 2011. She is a researcher in tissue engineering and regenerative medicine with multiple patents in the field. Her publication list comprises of more than 115 peer-reviewed articles including papers in Nature Materials and Advanced Materials. Her current research activities cover projects in treatment of complex multi-tissue oral and craniomaxillofacial defects, growth factor delivery and interfacial hard/soft tissue expansion, growth factor delivery, vascularization and stem cell seeding in patient specific 3D-bioprinted scaffolds.
Using growth factors in tissue regeneration has generated great enthusiasm and an intensive research effort leading to recent clinical trials, many of which have yielded unsatisfactory outcomes. Interestingly, the trials with the most satisfactory results have shared a common denominator: the presence of a vehicle for controlled growth factor delivery.
Blood vessels provide oxygen and nutrients for tissues and remove waste products. A reduction or loss in vascularization can lead to tissue necrosis, tissue death and organ failure. Vascular endothelial growth factor (VEGF) is an important vasculogenic and angiogenic agent which regulates signaling, proliferation and migration of endothelial cells. The VEGF pathway is critical for bone regeneration by promoting activity of bone forming cells and mobilization of involved progenitor cells.
However, the delivery of VEGF is specifically sensitive and should be localized and transported to a specific target tissue which requires a prolonged and sustained exposure to a low dose of VEGF. A bolus injection, imprecise use (off targeting), or unsatisfactory drug delivery can increase the threat of unwanted side effects and often lead to tumorigenesis. Currently, delivery systems are imperfect and limited technologies exist for precise encapsulation of VEGF and its sustained and controlled release. The use of microparticles as vehicles can provide an efficient and directed means for VEGF delivery that can be controlled, localized and released in a sustained fashion.
In this project using a new microfluidic approach, we will develop a method that creates precise customized encapsulated VEGF particles with well-regulated release rates. These particles can be embedded in scaffolds and implants designed for critically sized defects and used along with other growth factors to promote tissue regeneration and repair in oral and craniomaxillofacial injuries.