Nakahara Hiroyuki, Misawa Haruo, Hayashi Takahiro, Kondo Eisaku, Yuasa Takeshi, Kubota Yasuhiro, Seita Masayuki, Kawamoto Hironobu, Hassan Wael A R A, Hassan Reham A R A, Javed Shahid M, Tanaka Masato, Endo Hirosuke, Noguchi Hirofumi, Matsumoto Shinichi, Takata Katsuyoshi, Tashiro Yuichi, Nakaji Shuhei, Ozaki Toshifumi, Kobayashi Naoya
Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
Transplantation. 2009 Aug 15;88(3):346-53. doi: 10.1097/TP.0b013e3181ae5ba2.
Human mesenchymal stem cells (hMSCs) are multipotent stem cells found in the adult bone marrow that have the capacity to differentiate into various mesenchymal cell types. The hMSCs may provide a potential therapy to restore damaged tissues or organs of mesenchymal origin; however, a drawback is their limited life span in vitro.
We immortalized normal hMSCs with retrovirally transmitted human telomerase reverse transcriptase cDNA. One of the immortalized clones (YKNK-12) was established, and the biological characteristics were investigated in vitro and in vivo.
YKNK-12 cells were capable of differentiating adipocytes, osetoblasts, and chondrocytes. Osteogenically differentiated YKNK-12 cells produced significant levels of growth factors BMP4, BMP6, FGF6, FGF7, transforming growth factor-beta1, and transforming growth factor-beta3.. Microcomputer tomography T and soft X-ray assays showed an excellent calvarial bone healing in mice after transplantation of osteogenically differentiated YKNK-12 cells. These cells expressed human-specific osteocalcin and increased the gene expression of runt-related transcription factor 2, alkaline phosphatase, osteocalcin, and osterix in the bone regenerating area. YKNK-12 cell transplant corrected the bone defect without inducing any adverse effects.
We conclude that hMSCs immortalized by transduction with human telomerase reverse transcriptase may provide an unlimited source of cells for therapeutic use in bone regeneration.
人骨髓间充质干细胞（hMSCs）是存在于成人骨髓中的多能干细胞，具有分化为多种间充质细胞类型的能力。hMSCs可能为修复间充质来源的受损组织或器官提供一种潜在的治疗方法；然而，一个缺点是它们在体外的寿命有限。
我们用逆转录病毒转导的人端粒酶逆转录酶cDNA使正常hMSCs永生化。建立了一个永生化克隆（YKNK - 12），并在体外和体内研究了其生物学特性。
YKNK - 12细胞能够分化为脂肪细胞、成骨细胞和软骨细胞。经成骨分化的YKNK - 12细胞产生了显著水平的生长因子BMP4、BMP6、FGF6、FGF7、转化生长因子 - β1和转化生长因子 - β3。微型计算机断层扫描T和软X射线检测显示，经成骨分化的YKNK - 12细胞移植到小鼠体内后，颅骨愈合良好。这些细胞表达人特异性骨钙素，并增加了骨再生区域中与矮小相关转录因子2、碱性磷酸酶、骨钙素和osterix的基因表达。YKNK - 12细胞移植纠正了骨缺损，且未引起任何不良反应。
我们得出结论，通过转导人端粒酶逆转录酶而永生化的hMSCs可能为骨再生治疗提供无限的细胞来源。
