Mesenchymal stem cells are a highly promising source of cells for regeneration therapy because of their multilineage differentiation potential. However, distinct markers for mesenchymal stem cells are not well-established. To identify new candidate marker genes for multipotent human dental pulp stem cells, we analyzed the characteristics and gene expression profiles of cell clones obtained from a single dental pulp specimen derived from an 11-year-old female patient. Fifty colony-forming single cell-derived clones were separately cultured until the cessation of growth. These clones varied in their proliferation abilities and surface marker (STRO-1 and CD146) expression patterns, as well as their odontogenic, adipogenic, and chondrogenic differentiation potentials. Four clones maintained their original differentiation potentials during long-term culture. Gene expression profile by DNA microarray analysis of five representative clones identified 1227 genes that were related to multipotency. Ninety of these 1227 genes overlapped with genes reportedly involved in 'stemness or differentiation'. Based on the predicted locations of expressed protein products and large changes in expression levels, 14 of the 90 genes were selected as candidate dental pulp stem cell markers, particularly in relation to their multipotency characteristics. This characterization of cell clones obtained from a single specimen of human dental pulp provided information regarding new candidate marker genes for multipotent dental pulp stem cells, which could facilitate efficient analysis or enrichment of multipotent stem cells.
Keywords: Dental pulp; Differentiation; Gene expression profiles; Mesenchymal stem cells (MSCs); Surface marker genes.