SUMMARY To examine transcription factor (TF) network(s), we created mouse ES cell lines, in each of which one of 50 TFs tagged with a FLAG moiety is inserted into a ubiquitously controllable tetracycline-repressible locus. Of the 50 TFs, Cdx2 provoked the most extensive transcriptome perturbation in ES cells, followed by Esx1, Sox9, Tcf3, Klf4, and Gata3. ChIP-Seq revealed that CDX2 binds to promoters of up-regulated target genes. By contrast, genes down-regulated by CDX2 did not show CDX2 binding, but were enriched with binding sites for POU5F1, SOX2, and NANOG. Genes with binding sites for these core TFs were also down-regulated by the induction of at least 15 other TFs, suggesting a common initial step for ES cell differentiation mediated by interference with the binding of core TFs to their target genes. These ES cell lines provide a fundamental resource to study biological networks in ES cells and mice.

The in vitro differentiation and immunosuppressive capacity of mesenchymal stem cells (MSCs) derived from synovial fluid (SF-MSCs) and bone marrow extract (BM-MSCs) in an isogenic background of minipigs were comparatively analyzed in a collagen-induced arthritis (CIA) mouse model of rheumatoid arthritis (RA). The proliferation capacity and expression of pluripotent transcription factors (Oct3/4 and Sox2) were significantly (P<0.05) higher in SF-MSCs than in BM-MSCs. The differentiation capacity of SF-MSCs into adipocytes, osteocytes and neurocytes was significantly (P<0.05) lower than that of BM-MSCs, and the differentiation capacity of SF-MSCs into chondrocytes was significantly (P<0.05) higher than that of BM-MSCs. Systemic injection of BM- and SF-MSCs significantly (P<0.05) ameliorated the clinical symptoms of CIA mice, with SF-MSCs having significantly (P<0.05) higher clinical and histopathological recovery scores than BM-MSCs. Furthermore, the immunosuppressive properties of SF-MSCs in CIA mice were associated with increased levels of the anti-inflammatory cytokine interleukin (IL)-10, and decreased levels of the pro-inflammatory cytokine IL-1β and osteoclast-related sRANKL. In conclusion, SF-MSCs exhibited eminent pluripotency and differentiation capacity into chondrocytes, addition to substantial in vivo immunosuppressive capacity by elevating IL-10 and reducing IL-1β levels in CIA mice.

The present study evaluated the alkaline phosphatase activity, cell cycle stage, expression of markers and early transcriptional factors, and in vitro differentiation into selected cell lineages of porcine stem/stromal cells (SCs) isolated from skin (SSCs), adipose, and ovarian (OSCs) tissues. Skin and adipose SCs were isolated from a 6-month-old miniature pig, whereas OSCs were isolated from a newly born piglet. Isolated cells exhibited fibroblast-like cell population with significant renewal capacity and formed colonies by cells out-growth. All cells were positive for alkaline phosphatase activity and showed a relatively lower population at G0/G1 phase of the cell cycle. SCs derived from all tissues were strongly positive for cell surface markers, such as CD29, CD44, CD90, and vimentin. Further, relatively lower expression of cytokeratin and immunophenotype markers, such as major histocompatibility complex II (MHCII) and swine leukocyte antigen (SLA), was also observed. SCs derived from all tissues positively expressed the transcription factors, such as Oct-3/4, Nanog, and Sox-2. After induction, all SCs successfully differentiated into osteocytes and adipocytes and expressed the lineage specific marker genes. Further, cells from all tissues exhibited their potential for in vitro oogenesis with morphological changes and expression of markers during the germ-cell formation, namely Oct-4, growth differentiation factor 9b, c-Mos, Vasa, deleted in azoospermia-like gene, zona pellucida C, and follicle stimulating hormone receptor. Apart from basic features and selected lineage potential among all types of cells, OSCs possessed a greater ability to differentiate into the germ cell lineage in vitro.

The three types of dental MSCs from a single donor broadly possessed similar cellular properties and can differentiate into neuronal cells; however, pulp derived MSCs showed higher neurogenic potential than the follicle and papilla, suggesting their use in future stem cells therapy for the treatment of neurodegenerative disorders.