在進行組織修復時，新的組織生長與發育需要適當的血管來傳送養分以及移除廢物，所以血管新生扮演非常重要的地位。脂肪幹細胞的取得及應用具有立即性，沒有道德倫理問題，且取得的細胞數量多，又有良好的分化能力，所以我們選擇脂肪組織為組織修復的細胞來源，利用幹細胞的特性，並以生醫材料膠原蛋白，作為細胞培養的立體支架，探討膠原蛋白基質對脂肪幹細胞血管新生影響，評估脂肪幹細胞是否適合做為組織修復之血管新生細胞來源。
實驗結果發現萃取的人類脂肪組織細胞有三群細胞。三群細胞進一步分析其分子標誌，確定三群細胞主要有兩類型的細胞：CD34+及CD45+的細胞，其中CD34+的細胞有30~40%。分析CD34+細胞的分子標誌，結果指出：(1)間葉幹細胞的分子標誌CD29比例佔49.3%、CD44比例佔79.02%、CD90比例佔96.61%，CD105比例佔4.62% (2)內皮前驅細胞的分子標誌CD34比例佔100%、FLK-1比例佔5.74%、CD133比例佔2.53%。所以CD34+細胞具有間葉幹細胞的分子特性。
我們也比較P0 Fresh (P0F) CD34+細胞與培養過的ADSCs-derived CD34+細胞之分子表現，發現CD34的表現只在P0F，經培養其表現便迅速下降，CD105則剛好相反。
另外，將ADSCs-derived CD34+細胞於二維膠原蛋白上或三維之膠原蛋白基質中進行培養，結果指出膠原蛋白可以促進vWF與SMA的表現，但CD31與NG2並不表現。將ADSCs-derived CD34+細胞於膠原蛋白中進行長達28天的培養，結果仍然一樣。由本研究結果，我們對ADSCs-derived CD34+細胞的基本特性有更進一步的了解，且ADSCs-derived CD34+細胞具有分化成血管的潛力，未來可以使用實驗室的PCM，搭配適當的生長因子，對血管新生做更深入的研究。

　　Blood supply is very important in tissues, especially during tissue repairing. In the latter context, autologous adipose-derived stem cells (ADSCs) can provide an immediate and abundant source for tissue repairing to differentiate into proper tissue cells without ethical conflicts. In the current study, ADSCs were chosen to investigate their angiogenic potential in collagen matrix in order to assess the suitability of ADSCs to facilitate vessel formation during tissue repairing.

　　The ADSCs from human adipose tissue contain three subsets of cells according to cell size and coarseness and which include CD34+ and CD45+ cells. The percentage of CD34+ cells is 30~40% in total. Various molecular markers were further analyzed in the purified CD34+ cells by flow cytometry. Some molecular markers representative of mesenchymal stem cells were detected and the CD29 is 49.3%, CD44 is 79.02%, CD90 is 96.61%, and CD105 is 4.62%. Molecular markers of endothelial progenitor cells in CD34+ cells were 100% of CD34, 5.74% of FLK-1, and 2.53% of CD133. The results indicated that the CD34+ cells have somewhat the characteristics of mesenchymal stem cells and endothelial progenitor cells. The markers of CD34 subsided and CD105 elevated after cell culturing.

　　The expressions of vWF and SMA were stimulated after culturing ADSCs-derived CD34+ cells on or in collagen matrix. The molecular markers of CD31 and NG2, representative of mature endothelial cells and pericytes respectively, were not detected in this system even cultured for 28 days. In conclusion, ADSCs-derived CD34+ cells may have angiogenic potential to differentiate into cells related to vessel formation in collagen matrix.

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