[Multiple differentiation potential of human periodontal ligament stem cells expressing stromal cell antigen 1 (STRO-1) sorted by MACS].

Objective To perform in vitro characterization and comparison of stromal cell antigen 1 (STRO-1) positive (STRO-1⁺) and negative (STRO-1^-) cell populations from human periodontal ligament cells sorted by magnetic-activated cell sorting (MACS). Methods Periodontal ligament cells were isolated from the periodontal ligament by tissue digesting method. The cells were magnetically sorted using anti-STRO-1 antibodies. Subsequently, cells were characterized by flow cytometry for the expression of CD90, CD105, CD29, STRO-1, CD34 and CD45. Colony-forming assay was used to detect the ability of colony-forming. When the cells are induced to differentiate by osteogenesis and lipogenesis, alizarin red staining, and oil red O staining were used to identify the pluripotent differentiation of STRO-1⁺ and STRO-1^- cells. Results STRO-1⁺ cells highly expressed CD105 and CD90 and lowly expressed the haematopoietic markers CD45 and CD34. In contrast to STRO-1^- cells, STRO-1⁺ cells showed a significantly higher number of colony-forming units (CFUs). STRO-1⁺ cells were demonstrated to have osteogenic and adipogenic differentiation potential. Conclusion STRO-1⁺ cells isolated by MACS are human periodontal ligament stem cells with stem cell characteristics.