Method: Primary human PDL MSC cultures were isolated and grown as described by Seo et al (2004, The Lancet) and subcultured in the presence or absence of 10ng/ml PDFG-BB. Maintenance of MSC characteristics during in vitro expansion was tested by flow cytometric analysis of expression of MSC cell surface markers including CD146. To determine maintenance of differentiation potentials, aliquots of MSCs at alternate passages were placed into either osteogenic or adipogenic medium and assessed using qRT-PCR, mineralisation and adipogenesis assays.
Result: Total cell population doublings for 3 of the 4 PDL MSC cell lines were greater in the presence of PDGF-BB. Expression of CD146 persisted until senescence and loss of differentiation potential. Cells preferentially underwent osteoblastic rather than adipogenic differentation but differentiation potential was lost completely by 10 passages.
Conclusion: The extensive expansion potential of PDL MSCs in vitro was enhanced in the presence of PDGF-BB without decreasing existing differentiation capacity. Addition of PDGF-BB to cultures may have utility in PDL MSC expansion for regenerative therapy applications.