高分子奈米粒子做為子宮頸癌疫苗新型DNA傳輸載體之研究

Abstract

子宮頸癌是目前台灣女性的十大死因之一，根據2006年衛生署的資料，我國在2005年共有874位女性因子宮頸癌死亡，每十萬名女性的死亡率為 7.8%，是導致女性因癌症而死亡的第五位。近年的研究中指出，導致子宮頸癌的主要因素是女性經由性交而感染“人類乳突病毒”(Human Papilloma Virus, HPV)，造成子宮頸或陰道的細胞產生病變。目前對於子宮頸癌的治療，仍停留在早期發現早期治療的階段。而新興的預防醫學中，DNA疫苗是個現今被廣泛討論也較具有成效的方法。 本研究的主要目的是希望找出奈米級的高分子粒子，以取代奈米金粒子做為子宮頸癌DNA疫苗的載體，並希望能夠找出這個系統對於提升體T細胞免疫效果的最適條件。實驗中藉由將腫瘤細胞上的特定DNA(E7)作為抗原，並結合calreticulin(CRT)，接著利用高分子奈米粒子做為DNA載體，製成DNA疫苗。此DNA疫苗便具有抗原特異性與抗血管生成的特性，且具有疫苗與免疫治療的效果，由於載體採用高分子粒子也可降低DNA疫苗的成本。再本研究同時也探討高分子奈米粒子的粒徑大小做為DNA載體對DNA疫苗的影響 。 在本研究中，首先我們先以PMMA、PS、UHMWPE、PCL和Chitosan等五種不同特性的奈米粒子，和五種不同粒徑大小的PMMA奈米粒子，來做為子宮頸癌DNA疫苗載體。由測定細胞激素TNF-α的實驗中顯示以PMMA 4做為DNA載體，對於刺激巨噬細胞造成免疫反應的效果最強。而由動物實驗部分我們可以發現以PMMA 4奈米粒子做為DNA載體，在老鼠體內所呈現的免疫效果最佳。由以上實驗結果我們可以發現，以高分子粒子做為DNA疫苗的載體是一可行的方式。

In Taiwan, cervical cancer is one of the most common causes of death among women. As to the cancers, cervical cancer stands the fifth place and caused 874 women to die last year. The estimated mortality is 7.8/100,000 woman per year. Recent researches have indicated that HPV is the leading cause of cervical cancer. This is a virus that spreads most commonly by sexual contacts, leading to the pathological changes of the cervix or the vagina. Till now, we have no efficient treatments to this cancer. However, in the developing preventive medicine, DNA vaccine is considered a more practical treatment. In this study, we wanted to find more suitable nanoparticle to change the nanogold as vectors of DNA vaccine for cervical cancer. We explored the linkage of CRT to a model tumor antigen, human papilloma virus type-16 (HPV-16)E7, for the development of a DNA vaccine. This vaccine is antigen-specific and antiangiogenesis and has the effects of both vaccine and immune treatment. Because we used nanoparticle as the vectors, the costs were down dramatically. Then we explored the influences of the different particle size to DNA vaccines. We used PMMA, PS, UHMWPE, PCL, and Chitosan as cervical cancer DNA vaccine vector .In the analysis of TNF-α, PMMA 4 is the best DNA vector to massively stimulate macrophages and induce immune responses. In animal models, PMMA 4 as a DNA vector also can in mice. Result of this experiment, we can to believe it is a possible way to use polymer particle as DNA vaccine vector.