骨粘連蛋白（SPARC），為細胞基質醣蛋白，參與調控細胞增生、遷移、分化、胚胎發育、血管新生及骨質形成等功能。我們發現於體外進行含有 10 % 胎牛血清情況下培養，添加人類基因重組骨粘連蛋白（recombinant SPARC，rSPARC）對於人類脂肪幹細胞具有促進其增生的效果。P4 人類脂肪幹細胞經添加 rSPARC 培養七天後，利用 MTS 檢測細胞活性，10 μg/mL rSPARC 添加組對照控制組增加多達 80% 細胞活性，另外 10 μg/mL rSPARC 處理的組別也有較多的 BrdU 擷取量。rSPARC 對於臍帶間質幹細胞與牙髓幹細胞在含 10 % 血清培養條件下細胞增生的影響不如脂肪幹細胞明顯。
rSPARC 對於脂肪幹細胞、臍帶間質幹細胞與牙髓幹細胞無血清培養條件下，經MTS法、BrdU法發現細胞活性與增生能力都有增加的效果，且 rSPARC 對促細胞增生的效果有隨著細胞代數增加而有減少的趨勢，另外經由直接細胞計數也有一致的結果。
此外在不含分化因子的條件下，僅添加 rSPARC 於培養基中，三種間葉幹細胞分別培養 14 天後，並不會誘導脂肪幹細胞、牙髓幹細胞與臍帶間質幹細胞進行脂肪或硬骨分化。脂肪幹細胞、牙髓幹細胞與臍帶間質幹細胞經添加rSPARC培養兩週後，仍保有脂肪分化與硬骨分化潛能。
rSPARC 具促進間葉幹細胞增生效果，但不為一個分化誘導因子，不會誘導其走向脂肪或硬骨分化，且經過 rSPARC處理兩週後，間葉幹細胞能維持其分化潛能，顯示rSPARC具有促進間葉幹細胞自我更新的功能，而在這之前並無文獻指出 SPARC 有促進間葉幹細胞自我更新的功能，本研究為發表此現象的首篇研究。

SPARC, also named Osteonectin, is a matricellular glycoprotein involving in the regulations of cell proliferation, migration, differentiation, embryogenesis, angiogenesis and bone formation. Mesenchymal stem cells ( MSCs ) are currently exploited in numerous clinical trials to investigate their potential in immune regulation, hematopoiesis and tissue regeneration. Currently applied doses are in 2–15 millions cell/kg body weight range, thus a fast and reliable ex-vivo expansion method is needed to meet the highly demanding cell dose.
Occasionally, we found that the recombinant SPARC ( rSPARC ) expressed by E .coli can promote the proliferation of human adipose-derived stem cell ( ADSC ) in 10% FBS culture condition. The cell variability of 10 μg/mL-rSPARC-treated ADSC has been elevated up to 180% compared to control group for 7 days-culture. The cell variability of dental pulp stem cell ( DPSC ) and umbilical cord mesenchymal stem cell ( UCMSC ) also have been significantly promoted by rSPARC treatment in serum free culture condition but not obversely in the 10% FBS culture condition. The promotive effect of rSPARC on the proliferation of those MSCs is decreased by the increasing cell passage number.
rSPARC, has no stimulation effect on adipogenesis and osteogenesis to ADSC, DPSC and UCMSC, has been proved in the follow experiments. After pre-treatments of rSPARC for 14 days, ADSC and DPSC both still maintain the muti-potency of adipogenesis and osteogenesis.
rSPARC has promotive effect on the proliferation of MSC and is not a stimulator for differentiation. rSPARC-treated MSCs still maintain the muti-potency of adipogenesis and osteogenesis. Thus, rSPARC promote Self-renewal of ADSC, DPSC and UCMSC. This is the first research to reveal the promotive effect of SPARC on the self-renewal of mesenchymal stem cells.

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