由於關節軟骨組織有限的修復能力，對於罹患關節疾病的病人來言，發展組織工程軟骨是必須的。組織工程的軟骨是利用生物相容性和生物可分解性的載體培養軟骨細胞，製備近似可供植入的軟骨組織。天然關節軟骨主要由膠原蛋白第二型和較大的蛋白醣聚合體(proteoglycans，簡稱PGs)與透明質酸(hyaluronan 簡稱HA)組成，而蛋白醣單體最主要的醣胺素(glycosaminoglycans，簡稱GAGs)是硫酸化軟骨素(chondroitin sulfate，簡稱CS)。本研究已由牛氣管純化出膠原蛋白第二型，並利用不同冷凍溫度(-20℃、-80℃與-196℃)與冷凍乾燥法製備具多孔性的支架，孔洞大小分佈範圍為20–260μm，孔隙度為95％±1。再利用交聯劑genipin (GP)將CS和膠原蛋白第二型纖維及HA交聯，以製備三種支架COL II、COL II/CS (CCS)與COL II/CS/HA (CCH)，交聯後雖然有塌陷的現象，但仍具有孔洞結構，且具高含水率(132□145%)及高孔隙度(95□92%)特性，孔洞大小範圍為106–173□m。此外支架經過交聯後，增加了機械強度與變性溫度、提升抵抗酵素消化的能力與抗原性降低等。至於支架中CS與HA含量，CCS中CS含量為17.8±1.2 (μg/matrix)，而CCH中CS與HA的含量分別為15.6±2.3 (μg/ matrix)與22.55±1.8 (μg/ matrix)。本研究中我們評估COL II、COL II/CS與COL II/CS/HA支架對人類軟骨細胞的增生與分化影響。由組織切片可觀察到，軟骨細胞均勻遍佈在所有支架之中，並顯示圓形的型態。根據DNA與GAGs含量，CCH支架分別是21.3 □g/ matrix與150.15□g/ matrix皆高於COL II支架與CCS支架。此外，於統計學上CCH中軟骨細胞的基因表現，如aggrecan、 type II collagen、COMP 與 type X collagen gene等，相較於COL II支架，具有顯著的差異。再者，根據alcian blue染色與免疫組織染色的結果，CCH支架上有較多PGs、collagen type II與aggrecan的沈積。實驗結果顯示，CCH支架具有產生組織工程軟骨的潛能。
為了解決工程軟骨上細胞來源的限制，本研究評估人類臍帶血間葉幹細胞(human umbilical cord blood mesenchymal stem cells (UMSCs))，於COL II支架上分化成為軟骨細胞的潛能。並評估植入的幹細胞數目與COL II支架，對於UMSCs增生與分化的影響。幹細胞數目對分化之影響，由實驗結果顯示，相較於其他兩組細胞數目(6.05 ×104 cells/ml與6.05 ×105 cells/ml)，高細胞數目組(1.21 ×106 cells/ml) DNA與GAGs之含量及軟骨細胞特定基因的表現，隨誘導分化時間明顯達到最高值。表示幹細胞數目影響間葉幹細胞分化能力。
至於COL II支架對UMSCs分化之影響，根據實驗結果顯示，支架內細胞產生PGs和軟骨細胞特定基因之表現與軟骨細胞標誌ECM沈積。其表示交聯後的COL II支架，仍具有促進UMSCs分化成軟骨細胞的功能。然而，UMSCs於IM (induction medium)系統中培養， 其PGs之生化合成量、軟骨細胞特定基因之表現與標誌ECM的累積，皆高於BM系統。這結果可能意味著COL II支架與生長因子之間，存在syngerism的作用。
由不同支架影響UMSCs分化的結果顯示，CCH支架促進幹細胞的分化，collagen type II與aggrecan mRNA的表現量，相較於COL I與chitosan支架，具有顯著的差異。至於ECM生成量也相對較高。於In vivo實驗中，由組織切片的結果顯示，CCH支架生物相容性非常的好。根據細胞基因表現與軟骨標誌ECM之螢光染色的結果，我們可以推論CCH支架，對於以幹細胞修復關節軟骨組織的治療，是個非常良好的載體。

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