Differentiation of human labia minora dermis-derived fibroblasts into insulin-producing cells

Recent evidence has suggested that human skin fibroblasts may represent a novel source of therapeutic stem cells. In this study, we report a 3-stage method to induce the differentiation of skin fibroblasts into insulin-producing cells (IPCs). In stage 1, we establish the isolation, expansion and characterization of mesenchymal stem cells from human labia minora dermis-derived fibroblasts (hLMDFs) (stage 1: MSC expansion). hLMDFs express the typical mesenchymal stem cell marker proteins and can differentiate into adipocytes, osteoblasts, chondrocytes or muscle cells. In stage 2, DMEM/F12 serum-free medium with ITS mix (insulin, transferrin, and selenite) is used to induce differentiation of hLMDFs into endoderm-like cells, as determined by the expression of the endoderm markers Sox17, Foxa2, and PDX1 (stage 2: mesenchymal-endoderm transition). In stage 3, cells in the mesenchymal-endoderm transition stage are treated with nicotinamide in order to further differentiate into self-assembled, 3-dimensional islet cell-like clusters that express multiple genes related to pancreatic beta-cell development and function (stage 3: IPC). We also found that the transplantation of IPCs can normalize blood glucose levels and rescue glucose homeostasis in streptozotocin-induced diabetic mice. These results indicate that hLMDFs have the capacity to differentiate into functionally competent IPCs and represent a potential cell-based treatment for diabetes mellitus.

Trends and clinical application of induced pluripotent stem cells

The generation of induced pluripotent stem cells (iPSCs) from somatic cells demonstrated that adult mammalian cells can be reprogrammed into a pluripotent state by introducing defined transcription factors. iPSCs show almost identical properties in self-renewal and pluripotency, and can circumvent ethical concerns because they do not use embryonic materials. Therefore, iPSCs from a patient's somatic cells have great potential in studying drug development and regenerative medicine. Several human disease models have already been established using patient-specific iPSCs from Parkinson's disease and familial dysautonomia. Moreover, the correction of genetic defects by homologous recombination has already been accomplished with Fanconi anemia patient-specific iPSCs. However, the generation of patient-specific iPSCs for clinical application requires alternative strategies, because genome-integrating viral vectors may raise tumorigenic risk after transplantation. Moreover, the use of iPSCs for eventual clinical application is limited by the low efficiency of current methods for reprogramming. Studies on the mechanism underlying the reprogramming and on establishment of non-integration methods contribute evidence toward resolving the safety concerns associated with iPSCs. Small molecules involved in the epigenetic modification and signaling pathway not only improve reprogramming efficiencies, but also bypass the addition of certain reprogramming factors. However, reprogramming somatic cells purely by small molecule treatment still remains a challenge. Here, we review recent progress made by the use of transcription factors and small molecules that can either replace reprogramming factors or enhance reprogramming efficiency. We also discuss the progress that has been made in the rapidly moving iPSC field, with an emphasis on understanding the mechanisms of cellular reprogramming and its potential application to cell therapy.

Efficient culture system for human embryonic stem cells using autologous human embryonic stem cell-derived feeder cells

Human embryonic stem cells (hESCs) need feeder cells for their maintenance in an undifferentiated state. In conventional culture systems, mouse embryonic fibroblasts (MEFs) serve as feeder cells to maintain hESCs. However, the use of MEFs elevates the risk of transmitting mouse pathogens and thus limits the potential of hESCs in cell replacement therapy. Consequently, the use of human feeder cells would be an important step forward in this in vitro technology. To address this issue, we used fibroblast-like cells differentiated from the Miz-hES6 hESC line (Diff (Miz-hES6)) as feeder cells to support the in vitro growth of three hESC lines. Immunofluorescence microscopy and reverse transcription-PCR assessing the expression of undifferentiated hESC markers revealed all three hESC lines were maintained in an undifferentiated state. In vitro proliferation proceeded as efficiently as when the hESCs were cultured on MEFS. Moreover, karyotype analysis revealed the chromosomal normality of the hESC lines and the Diff (Miz-hES6) feeders themselves after even 50 passages. Furthermore, the hESC lines maintained their pluripotency since they remained capable of forming embryoid bodies (EBs) in vitro. Thus, hESC-derived fibroblast-like cells successfully support in vitro hESC propagation.

A Case of Colonic Metastasis of Recurrent Cervical Cancer / 대한산부인과학회잡지

It is estimated that approximately 35% of patients with invasive cervical cancer will have recurrent or persistent disease following therapy. The common metastatic sites of recurrent cervical cancer included the lung, liver and vertebra, however, colon metastases from cervical cancer were extremely rare. Recently we experienced a case of colonic metastasis in a patient with cervical cancer who had been treated with radiation and chemotherapy. We present this case with a brief review of literature.

A histologic study of initial change and repair of tooth and periodontal tissue in extrusion of young adult dogs / 대한치과교정학회지

This study was carried out in order to study early histologic changes and repair reaction appling to extrusive force for 3rd premolar of adult dogs. After 1 week of extrusive force with elastic chain, one of dogs was sacrified and after 3 weeks retention period, another dog was sacrified. The paraffin sections of samples were stained with Hematoxylin - Eosin and Masson's Trichrome and were examed by light microscopy . The obtained results as follows. 1, In Hematoxylin - Eosin and Masson Trichrome stain of control group , the periodontal ligament width was constant from apical third to cervical third of the root and periodontal fiber arrangement was horizontal or oblique in cervical third, oblique in middle third, oblique in apical third of root. in alveolar bone, smooth appearance was shown. 2. In Group 1, all periodontal fiber arrangement was oblique toward tooth, and the periodontal ligament width increased . Partially PDL was ruptured in apex. In MT stain, immature bone formation was seen at alveolar crest area. Active bone formation was observed along the one side of alveolus, and apical portion of pulp was involved with blood vessel rupture , vacuolization of pulp tissue and hyperemia. 3. In Group 2, most periodontal ligament arrangement and PDL width was repaired and fiber density increased In MT stain, mineralization of immatuie bone on the alveolar crest was progressed. In pulp, vacuole and hyperemia was diminished and fibrotic change was diminished. 4. After 3 week periodontal ligament has more repair ability than pulp tissue. pulp was involved with vacuolization and fibrosis, so it takes more time for repair.