近幾年來桿狀病毒的適用範圍越來越廣，但是受限於一些先天條件、無法真正廣泛應用。 其中影響最大的兩個因子為：一、脫水或高溫會讓桿狀病毒完全喪失感染昆蟲細胞與轉染哺乳類細胞的能力。 二、桿狀病毒轉染入不同細胞的效率有異。 本研究以解決此二問題為主要宗旨： 第一部份 設計研發適當的添加劑來克服脫水或高溫的影響。 由我們的結果顯示在含有胎牛血清與 sucrose 配方下，能使病毒克服乾燥與高溫貯存的環境，在病毒長時間乾燥貯存方面、此配方仍然顯現出相當保護力。 對於桿狀病毒應用於藥物快速量產篩選、臨床試驗、或病毒之長距離運送及長時間保存，本配方是一個最佳的桿狀病毒保護添加劑。 第二部份提升桿狀病毒的轉染力。 由於桿狀病毒屬於昆蟲病毒的一種，若病毒進入細胞的比例增加一定能增加外源蛋白質的表現量。 因此、我們利用穿膜蛋白來製作假型包裝病毒（pseudo-type virus）的方式來改善病毒進入細胞的效率。 由結果顯示，假型包裝病毒除了本身對哺乳類細胞的轉染力有明顯提升外，還能增進同時轉染之其他桿狀病毒的轉染效率。 在增加外源蛋白表現方面，還可以配合其他的方法來放大外源蛋白質的表現量，如額外添加sodium butyrate 與轉染 vIE2。 桿狀病毒是一個應用性廣又具潛力系統，但是這個系統受限於一些先天的條件，使其應用受到些許阻礙，如果這些阻礙能被突破，桿狀病毒的應用性將更加廣大。 本研究的結果正好可以提供一些改進的方法，以最簡便的方式提升病毒對環境的抗性，並提供一個創新的方法來提升病毒轉染力。

Recent years, baculovirus has become an important and popular vector for emerging applications, however, its application is restricted due to a difficulty to store and enter into mammalian cells. Dehydration and high temperature decrease viral variability and viral transduction efficiency into mammalian cells, and experiments are needed to resolve these problems. In part I, an optimized formula was developed to preserve the activity of baculovirus stocks during prolonged periods of dehydration and in various storage temperatures. Dehydration of baculovirus can totally obliterate its ability to infect insect cells and the transduction of mammalian cells. Our results showed sucrose and fetal bovine serum can maintain baculovirus transduction efficiency for weeks post dehydration and high temperature treatments. The formula would be an excellent additive to baculovirus stocks used for high throughput drug screening, long distance transportation or long term storage. In part II, ways to enhance baculovirus transduction efficiency were developed. Since baculovirus is a safe and popular tool for foreign protein production in the mammalian cells, if virus entrance could be enhanced, foreign gene expression should be greatly increased. In this study, we used pseudo-type virus containing engineered trans-membrane proteins to overcome the barrier on baculovirus entrance. Our results showed that not only pseudo-type viruses themselves, but also other simultaneously co-transduction viruses had better transduction efficiency. In addition, transduction of the virus can be immensely boosted by the addition of sodium butyrate or co-transduction of vIE2. Baculovirus is a safe and useful system, and it can serve as a tool for better protein expression in mammalian cells with high quality, but it encounters some restriction in application. These experiments provided one optimized formula to improve baculovirus stability under preservation, and in addition, provided methods to assist better transduction of baculovirus into mammalian cells.

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