斜紋夜蛾（Spodoptera litura）（Lepidoptera: Noctuidae）核多角體病毒對大鼠毒性與致病性之安全評估

Safety assessment of acute toxicity and pathogenicity for Spodoptera Iitura nucleopolyhedrovirus in rats

本試驗主要為支援病毒類微生物製劑產品開發過程中原體之安全評估，以提供生物性農藥產品商品化所需的毒理資料。以1 x10^8 PIB/ml之Spodoplera litura核多角體病毒（nucleopolyhedrovirus，NPV）（SpltNPV）包涵體，進行大鼠口服（10 ml/kg體重）與氣管灌注（1ml/kg體重）毒性與致病性之安全評估。口服與肺急毒性試驗以Spraque -Dawley（SD）品系大鼠分為A、B、C、D、E共5組，其中A-C為處理組，D與E組為高壓滅菌與空白組，分別在第1、3及21天評估致死率、臨床症狀、體增重、臟器重量、血液學、血清生化、血清蛋白電泳、聚合酶鏈鎖反應偵測病毒及組織病理判讀。結果顯示經SpltNPV口服後無任何大鼠死亡，亦無明顯的臨床症狀，體重增重、肉眼病變等與空白組比較亦無明顯差異，臟器重量方面第21天處理組大鼠肝臟顯著低於滅菌組。大鼠氣管灌注後肺臟可見明顯的發炎反應，體重除第1及第3天顯著低於空白組（p＜0.05）外，第21天體重則無明顯差異;血清生化分析顯示尿酸（Uric acid）顯著高於空白組（p＜0.05）；處理組與、滅菌組肝臟重量組織顯著低於空白組，肺臟重量則顯著大於空白組。血清蛋白方面，口服與氣管灌注試驗第1、3與21天處理組及對照組大鼠皆真相似之SDS-PAGE血清蛋白圖譜與濃度。經由（35/36）引子監測臟器內純化的DNA，並未在大鼠肺臟與其他組織臟器增幅出680 bp的病毒基因片段。綜合上述結果顯示，SpltNPV對大鼠無明顯之口服與肺急毒性或致病性。此試驗研究除了建立較完整之病毒類微生物製劑對溫血動物之安全評估系統外，並可支援SpltNPV微生物製劑產品之商品化及對此類產品管理政策訂定之參考。

"The purpose of this study is to evaluate the acute toxicity and pathogenicity of Spodoptera litura nucleopolyhedrovirus (SpltNPV) in rats for supporting registration required data of commercial bioinsecticides. A dose of 1x10^8 PIB/ml of SpltNPV inclusion body was used for acute oral (10 ml/kg body weight) and pulmonary (I ml/kg body weight) toxicity assessment. Spraque-Dawley rats were divided into A, B, C, D and E groups, which A-C were treatment groups and D and E were autoclaved and control groups, respectively. The assessment was itemized as mortality, clinical symptoms, pathological changes, body weight gain, organ weights, hematological parameters, serum chemical parameters, SDSPAGE of serum proteins and polymerase chain reaction detection. Animals with oral administration showed no significant toxic signs or death, and no significant differences in body weight gains and gross or microscopic pathology in comparison with control rats; but the liver weight was significantly lower than the control group on 21, I day. In the acute pulmonary toxicity study, the lungs of the treated rats showed a marked inflammation. The body weight gains decreased significantly in the treated rats on 1st and 3rd day (p ＜0.05). In the serum biochemical analyses, the levels of uric acid of the treated rats were significantly higher than the control rats (p ＜0.05). The liver and lung weights in treatment and autoclaved groups were decreased and increased significantly, respectively, than the control group. The SDS-PAGE analyses of serum proteins showed that the profile and concentration of serum proteins were similar in all treated and control groups. A primer set (35/36) for amplifying a 680 bp of polyhedrin gene fragment was used, and no SpltNPV genes were amplified in lungs or other organs of the treated rats. Our results demonstrated that SpltNPV inclusion body has no significant effects of acute oral and pulmonary toxicity/pathogenicity in rats. This study not only establishes more complete evaluation system of viral biopesticides on animal but also provides management information for commercial SpltNPV biopesticides."