2016-11-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/713235摘要:於2013年末,台灣豬場爆發豬流行性下痢(PED)疫情,造成超過三十四萬頭小豬的死亡,重創台灣養豬業和民生經濟,雖然疫情在2015年後逐漸減輕,但是今年年初新型PED的疫情重新在台灣和美國延燒,證實新型PED疫苗開發及上市之迫切需要。台灣新型PEDV屬於高毒力之non S-INDEL病毒株,與美國及世界各國之強毒型PEDV極為相似,因此開發台灣新型病毒株之疫苗極具國際市場潜力。本計畫目的分成兩大部份,分別為減毒疫苗及不活化病毒疫苗之開發。過去本實驗室已成功從台灣田間豬隻的腸道中分離出新型病毒株PEDV-Pingtung (PT),並以綠猴腎細胞株連續繼代而獲得較接近原始初代病毒之第五代攻毒株(PEDVPT-P5)及第96代(PEDVPT-P96)高繼代病毒株。過去已建立以PEDVPT-P5於田間離乳豬之攻毒模式以及檢測PEDV病毒量和特異性血清學檢測系統,可供未來PED疫苗臨床前田間試驗使用;證實以高度繼代病毒株(PEDVPT-P96)經口給予五週齡豬隻可見顯著減輕甚至完全沒有感染症狀,並能夠提供足夠的保護力對抗強毒株(PEDVPT-P5)感染;此外,由於減毒疫苗開發所需要時間較長且用於非PED疫區預防PED將有使用上限制,為了因應目前田間豬場需求,本計畫亦將開發以接近田間分離株之PEDVPT-P5病毒株之不活化疫苗,以加速提供可於田間安全使用之疫苗。由於本病主要致害是在免疫系統尚未建立之新生仔豬,因此PED疫苗目標為具有完善免疫系統和快速腸上皮細胞更新速率的母豬,以誘導其產生移型免疫反應保護新生小豬。本計劃擬在3年的研究時間,進行評估PEDVPT-P96減毒株及PEDVPT-P5不活化病毒株對於懷孕母豬之免疫原性與生物安全性、PEDVPT-P96減毒株或PEDVPT-P5不活化病毒株誘導之被動免疫對於新生小豬之保護力、及其免疫效力維持之長短,以協助訂定未來完整母豬免疫及補強計畫。相信藉由本產學計畫之執行,能盡速的產製能夠有效控制PED之疫苗及免疫計畫供國內外田間豬場使用。<br> Abstract: The new virulent porcine epidemic diarrhea virus (PEDV) has spread worldwide since 2013. The devastating epidemics wiped out millions of piglets and severely impacted the swine industry. Therefore, a novel vaccine against the new variant of PEDV is urgently needed. The result of phylogenetic analysis of Taiwan PEDV strains indicates that these new variants are closely related to global novel non-S INDEL PEDV strains, suggesting that the PEDV strain might be a good parental strain for vaccine development to control global outbreaks of PED. We have isolated a non-S INDEL PEDV Taiwan strain, Pingtung 52 (PEDVPT), and serial passage it in Vero cells. A PEDV challenge model has been established by orally inoculation of the low passage (passage 5; PEDVPT-P5) in 5 week-old seronegative conventional piglets. Comparing with the PEDVPT-P5-inoculated piglets, which showed watery diarrhea and persistent viral shedding from1 day post-inoculation, piglets orally inoculated with the high-passage (passage 96; PEDVPT-P96) virus exhibited no or mild PEDV-associated diarrhea. The PEDVPT-P96-inoculated piglets were capable of inducing immune responses and neutralizing antibodies effectively protecting a subsequent PEDVPT-P5 challenge. For PEDV vaccine development, it is crucial for neonatal piglets to receive maternal antibodies from colostrum or milk from immunized sows in against of PEDVs. In this project, we first aim to evaluate the pathogenicity, immunogenicity, fecal viral shedding, and passive protection of nursing piglets provided by sows-inoculated with the PEDVPT-P96. Furthermore, while developing attenuated PEDV vaccines is a tricky and time-consuming process due to the safety issue is always the first concern, to accelerate PEDV vaccine development for controlling current global outbreaks, we also aim to develop an inactivate vaccine from the PEDVPT-P5 stock virus. The immunogenicity and immune protection in postweaning pigs, and passive protection of nursing piglets provided by sows inoculated with the inactive PEDVPT-P5 will be studied. After accomplishing the project, a live attenuated PEDV vaccine and an inactivated PEDV vaccine derived from the novel Taiwan virulent isolate will be expected to be developed for controlling global PED.豬流行性下痢病毒減毒疫苗不活化病毒疫苗母豬porcine epidemic diarrhea viruslive attenuated PEDV vaccineinactivated PEDV vaccinesow台灣新興豬流行性下痢病毒減毒及不活化疫苗之研發及其於母豬場保護哺乳豬之臨床保護效力