Conclusions
These results demonstrate that BMP2 gene transduction provides an effective method to enhance the osteogenic potential of USCs.
Methods
USCs were isolated from voided urine and transduced with Lentiviral vector encoding BMP2. An in vitro study was performed to detect Lentiviral-BMP2 transduced USCs differentiated towards osteogenic lineage. Furthermore, Lentiviral-BMP2 transduced USCs were transplanted in vivo to examine the ectopic bone formation ability. After six weeks, retrieval samples were obtained for immunostaining and histological analysis.
Results
The results showed that the transduction efficiencies were over 90%, and transduced USCs had high expression levels of the BMP2 gene and secreted BMP2 protein. Alkaline activity and mineral deposition staining demonstrated that transduced USCs differentiate into osteogenic lineages without the addition of osteogenic supplements. Transduced USCs also showed high expression of bone-related markers, including runt-related protein-2 (Runx2) and osteocalcin (OCN), confirming this lentiviral-BMP2 construct provides sufficient stimuli for osteogenic differentiation. Histological analysis indicated that the transduced USCs induced robust new bone formation in nude mice. Six weeks after transplantation, human derived cells were observed to participate in bone formation. Conclusions: These results demonstrate that BMP2 gene transduction provides an effective method to enhance the osteogenic potential of USCs.
