豬生殖與呼吸綜合症病毒ORF5與大腸桿菌熱溶解性腸毒素次單位B (LTB)之基因轉殖菸草次單位疫苗田間保護效力之研究

Protective Assessment of a Transgenic Tobacco Vaccine co-expressing Procine Reproductive and Respiratory Syndrome Virus GP5 and E.coli LTB in the Field

張權星(Chuan-Hsing Chang)

指導教授 ： 鄭謙仁

共同指導教授 ： 龐飛(Victor Fei Pang)

國立臺灣大學/獸醫專業學院/分子暨比較病理生物學研究所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.02452

摘要

豬生殖與與呼吸道綜合症是全球養豬產業具有嚴重影響之豬隻傳染病，主要造成保育豬嚴重呼吸道臨床症狀，以及母豬流產與死產等繁殖障礙，並經常併發細性肺炎等疾病，造成豬隻衰弱與生長性狀不佳，進而產生巨額經濟損失。由於PRRSV減毒活毒疫苗會排毒及有回毒風險，以及無交叉保護效力。本實驗室賈敏原等人 (2011)於無特定病原豬隻 (SPF)口服免疫豬生殖與呼吸綜合症病毒ORF5與大腸桿菌熱溶解性腸毒素次單位B (LTB)之基因轉殖菸草次單位疫苗，以同源病毒株進行攻毒，結果顯示本疫苗能誘發體液免疫與黏膜免疫，以及能減少血清病毒量，達到免疫保護效果。本研究將該疫苗使用於田間豬場，觀察其對豬隻生長性狀之實際效益以及免疫保護效力之變化。將240頭保育豬隨機分為4個試驗豬群，分別為基因轉殖PRRSV GP5-LTB菸草次單位疫苗組 (GP5-LTB T)、正常菸草組 (W T)、商業化MLV減毒疫苗組 (MLV)與對照組 (C)。豬隻5、7、9週齡時餵飼轉殖菸草 50 g/頭 三次。商用疫苗PRRS MLV則於5週齡時，接種一次。相關生長性能以及免疫反應結果顯示，四組豬群試驗前後均為PRRSV陽性不穩定之感染狀態，然而，GP5-LTB T組豬群於生長性狀的整體表現，呈現最佳狀態，其終末平均體重可達59.07公斤，平均日增重達473.5公克/天，並且具有四組最佳之飼料效率1.9 ; 顯示基因轉殖PRRSV GP5-LTB菸草次單位疫苗對於陽性感染豬隻在生長性狀上，具有降低飼料成本與縮短上市時間等生產潛力。本田間試驗結果顯示，基因轉殖PRRSV GP5-LTB菸草次單位疫苗於田間陽性保育階段豬群之生長性狀呈現正向之生長效益，具有持續發展的良好潛力，期盼未來能有助於本病的防疫與控制。

關鍵字

基因轉殖PRRSV GP5-LTB菸草次單位疫苗 ； 田間試驗 ； 生長性狀

並列摘要

Porcine reproductive and respiratory syndrome (PRRS) is a highly infectious and economically important viral disease in swine industry worldwide. The disease causes severe respiratory clinical signs in nursery pigs and induces reproductive disorder, including abortion and still borne in sows. Additionally, it commonly complicates with bacterial pneumonia and causes weaken and poor growth performance in the herd resulting in huge economic loss. Due to commercial live attenuated vaccine shows long shedding period and risk of virulent reversion with poor cross-protection against various strains. Chia et al., 2011 demonstrated an oral administration of transgenic PRRSV ORF5-LTB tobacco subunit vaccine was able to induce humoral and mucosal immunity; in addition, it also reduced the serum viral load after homologous virus challenging. In the present study, the transgenic PRRSV ORF5-LTB subunit tobacco vaccine was tested in the field to estimate the growth performance and immune protectivity. 240 nursery pigs were randomly assigned to 4 groups, including transgenic PRRSV ORF5-LTB subunit tobacco vaccine (GP5-LTB T), wild tobacco leaves (W T), IngelvacR PRRS MLV (MLV) and non-treatment control (C). In the GP5-LTB T, group transgenic tobacco leaves was oral fed 50 g per pig for three times at 5, 7 and 9 weeks old. Commercial MLV vaccine was injected at 5 weeks old in the group of V. The result showed PRRSV infectious status belonging to positive unstable condition before and after the trial. The group of GP5-LTB T demonstrated the best growth performance including its final average body weight achieved 59.07 Kg, its average daily weight gain was 473.5 g/day, and especially, its feed conversion ratio was 1.9. In conclusion, transgenic PRRSV subunit plant vaccine has the great potential to be a competitor for PRRS control in the future.

並列關鍵字

Transgenic PRRS tobacco vaccine ； Field trial ； Growth performance

參考文獻

Antibody response to porcine reproductive and respiratory syndrome virus

porcine reproductive and respiratory syndrome virus and B subunit of

Detection of Porcine Reproductive and Respiratory Syndrome Virus in Porcine

porcine reproductive and respiratory syndrome virus by intranasal delivery of a

porcine reproductive and respiratory syndrome virus. Comparative Immunology,