在幫助神經生長的治療中，幹細胞療法被視為是其中極具吸引力的一環，尤其是在一些神經退化疾病以及脊椎受傷的病人身上。成體脂肪幹細胞(ADSCs)屬於間葉幹細胞中的一員，與其他類型的幹細胞相比，其具有一下幾種優勢：可大量取得、較不會有倫理上的考量以及取得的方法上對病人較不具有侵犯性也較少傷害 成體脂肪幹細胞已被證實與骨髓幹細胞具有同等能力之多分化潛力，其並可被分化為多樣的中胚層細胞如脂肪、軟骨與骨頭細胞。除此之外，脂肪幹細胞亦被發現也具有跨胚層分化為神經細胞的可行性，這樣潛在的潛力使得脂肪幹細胞在使用成體幹細胞療法治療神經退化型疾病或是脊椎受傷的病人上具有一定的前景。在組織再生工程的發展上，使用各式各樣的生物材料來當作細胞鷹架以達成三度立體空間培養一直是很大的考量點。甲殼素是一種從幾丁質所萃取出來的天然多醣類，在基礎研究中常常被拿來做為輔助神經再生的生物材料，因其具有導引神經生長以及增進神經幹細胞存活的效果。除此之外甲殼素可為其他不同種類的細胞提供三度立體空間培養的介質，但尚無脂肪幹細胞之相關研究。此研究中我們將人類脂肪幹細胞種植在甲殼素表面上，根據其細胞存活而得到最佳的種植密度以及時間。自動形成之球狀體會表現神經細胞表面標記，同時隨著球體打散再植(Replating)的方式所形成之一級、二級與三級球體其所具有之神經分化潛力會隨之增加，此一將人體脂肪幹細胞種植在甲殼素表面以誘導出神經分化潛力之研究將有助於未來臨床上合併使用自體脂肪幹細胞與甲殼素通道以促進神經再生的相關應用。

The application of stem cells to facilitate nerve regeneration appeals to have great therapeutic potential in patients of neurodegenerative disease or spinal cord injury. The adipose derived stem cells (ADSC), a subset of mesenchymal stem cells, possess great advantage of abundant cell amount, less ethical issue, minimal invasive procedure when compared to other sources. The ADSCs have been proven similar potentials of multipotency comparing to bone marrow stem cells and can be differentiated into adipose, cartilage and bone as well. Moreover, the ability of trans-differentiation from ADSCs into neural lineage that provides a scope of post-natal stem cell therapy for the neurodegenerative disease or spinal cord injury. The three dimensional culture in tissue engineering using various biomaterials as scaffolds has drawn a great concern. Chitosan, a naturally derived polysaccharide from chitin, is widely studied to facilitate nerve regeneration using chitosan neural tube to guide the direction of nerve regeneration and to improve survival of neural stem cells. In addition, chitosan also serves as a three-dimensional culture substrate to form sphere in various cell types, but remains unexplored in ADSC. In this study, we seed the human ADSC on chitosan coated surface and obtained the optimization of the seeding density and timing of harvest according to cell viability assay. Spontaneous formation of sphere arises with expression of neural lineage markers (nestin, NFH and GFAP). The neural induction potentials are also provoked by replating protocol from the primary to the tertiary sphere. The effect of neural induction in human ADSC on chitosan coated surface may avail of future clinical implication to facilitate nerve regeneration using chitosan channel seeded with autologous ADSC.

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