| The delivery of human adult mesenchymal stem cells (hAMSC) using CaPSphers is a novel approach for use in bone tissue engineering. CaPSphers are calcium- and phosphate-based, biocompatible, and bioresorbable microcarriers that may serve as a delivery vehicle for hAMSC to critical-sized bone defects unable to heal by natural means. CaPSphers 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 attached to CaPSpers as determined by cell staining and scanning electron microscopy, and proliferated to yield several hundred hAMSC per CaPSpher two weeks after initial cell seeding. Under static culture conditions, approximately 30% of the available CaPSphers are seeded with hAMSC. hAMSC on CaPSphers cultured in the presence of an osteogenic supplement differentiated into osteoblasts as indicated by the expression of alkaline phosphatase activity. Cells of the MG-63 human osteosarcoma cell line also attached, proliferated, and differentiated as osteoblasts while cultured on CaPSphers. Thus, based on these in vitro results, CaPSphers may prove to be a useful vehicle to deliver adult stem cells for tissue engineering. |
