OBJECTIVETo isolate and cultivate human periodontal ligament stem cells (PDLSC) and to investigate the feasibility of PDLSC in vitro differentiation into chondrogenic phenotype.

METHODSPeriodontal tissue was obtained from healthy young human teeth extracted for orthodontic purposes. PDLSCs were isolated by single-colony selection and cultivated. PDLSC of passage 3 was plated at density of 1 x 10(7) cells/cm3 and induced with chondrogenic induction medium of DMEM containing TGF-beta1 (10 microg/L), IGF-1 (50 microg/L), dexamethasone (40 microg/L) and 10% FBS. In control group, the constructs were maintained in DMEM medium + 10% FBS. After 21 days induction, the results were evaluated by histology, histochemistry, immunohistochemistry and RT-PCR.

RESULTSThe constructs in experimental group were smooth and relatively firm in texture after 3 weeks of culture. Toluidine blue staining showed the formation of distinct lacuna structure. Positive staining of type II collagen was also detected by immunohistochemistry and it was confirmed by RT-PCR. In contrast, in the control group, the constructs collapsed gradually, lacuna was barely detected in histology and type II collagen expression negative.

CONCLUSIONSPeriodontal ligament contain stem cells can be isolated and cultivated. PDLSC have the potential of chondrogenic differentiation.