| The delivery of human adult mesenchymal stem cells (hAMSC) using CultiSphers is a novel approach for use in bone tissue engineering. CultiSphers are collagen-based, biocompatible, and bioresorbable microcarriers, which may serve as a delivery vehicle for hAMSC to critical-sized bone defects unable to heal by natural means. CultiSphers loaded with cells offer the advantage of being able to place a large number of cells directly and controllably in a wound site or on a tissue engineering scaffold. hAMSC will proliferate to yield approximately 70 hAMSC per CultiSpher three weeks after initial cell seeding. Under spinner culture conditions, over 95% of the available CultiSphers are seeded with hAMSC. hAMSC on CultiSphers cultured in the presence of an osteogenic supplement differentiate into osteoblasts as indicated by the expression of alkaline phosphatase and the deposition of calcium. In addition, hAMSC on CultiSphers will migrate off of the microcarriers when placed in stationary cultures. Thus, based on these in vitro results, CultiSphers may prove to be a useful vehicle to deliver adult stem cells for tissue engineering. |
