【作者】 么宏强；

【导师】 马学恩； 赵振华；

【作者基本信息】 内蒙古农业大学 ， 基础兽医学， 2006， 博士

【摘要】 绵羊肺腺瘤病(sheep pulmonary adenomatosis ,SPA)是由β型反转录病毒引起的一种肿瘤性传染病,世界动物卫生组织将其列为B类疾病,我国农业部列为三类疾病。本研究在对内蒙古某市种羊场绵羊肺腺瘤病进行流行病学调查的基础上,选择2个SPA自然病例带回实验室,进行临床症状观察、血液学检查、X线检查、病理剖检、病理组织学和超微病理学观察。同时用含JSRV-NM株的SPA肺肿瘤组织无细胞滤液0.3 ml气管内接种1日龄羔羊7只,经18个多月的系统观察,对存活下来的4只人工感染羊,也进行了同上的系统临床病理学研究。本研究还分别提取2只自然感染羊、4只JSRV-NM株人工感染羊、6只健康对照羊的肺组织基因组DNA,根据JSRV-NM株病毒基因组全序列,采用Primer Premier 5.0引物设计软件,在env基因TM区和LTR U3区序列设计一对引物,利用PCR方法,检测自然感染和人工感染SPA病羊肺肿瘤组织中JSRV的前病毒DNA。同时,对自然病例和人工感染病例,用流式细胞仪检测外周血中单核细胞、淋巴细胞和T淋巴细胞亚群的动态变化以及淋巴细胞和单核细胞凋亡情况。实验结果表明:(1)2只自然感染绵羊均出现了SPA典型的临床症状,“小推车试验”阳性,脉搏和呼吸频率高于正常,贫血,X线胸透发现病羊肺部有不同程度的云絮状实变区。(2)剖检可见,肺脏体积增大,表面和切面上有大小不一、质度较实的黄白色小结节,有些病例肺胸膜的脏层与壁层发生粘连,支气管、细支气管内可见白色泡沫状黏液。(3)病理组织学检查,肺泡壁上皮细胞和细支气管上皮细胞增生,呈乳头状向肺泡腔内或细支气管腔内生长,邻近肺泡腔内有大量脱落的上皮细胞。(4)透射电镜观察,病羊肺泡壁上皮细胞被大量肿瘤化的立方状上皮细胞取代,有些细胞的细胞质中发现有明显的板层小体,证明肿瘤细胞主要来源于Ⅱ型肺泡上皮细胞。(5)4只人工感染绵羊均出现了一些SPA临床症状。剖检、组织学检查以及透射电镜观察,人工感染JSRV-NM株病羊所引起的主要病变及其性质,和SPA自然病例的病变及其性质相似。(6)2只SPA自然病羊PCR检测结果都为阳性,而2只健康对照羊PCR检测结果都为阴性;4只JSRV-NM株人工感染病例PCR检测结果都为阳性,而4只健康对照羊PCR检测结果都为阴性。(7)2个自然病例、4个人工感染病例,外周血中CD2~+、CD4~+、CD8~+T细胞表现为暂短的升高,其后迅速下降,之后可反复出现起伏;而在JSRV的持续作用下,病羊体内的淋巴细胞和单核细胞呈现不同程度的凋亡和坏死。更多还原

【Abstract】 Sheep pulmonary adenomatosis (SPA) is a contagious tumour of sheep that is caused by the betaretrovirus. According to the OIE and the China ministry of agriculture classification, SPA is belong in the B-type and the third-type infectious disease, respectively.Based on the investigation of epidemiology, two natural cases with SPA from a region of Inner Mongolia were taken back to our laboratory,isolated until death .And the examination of clinical signs, blood samples, X-ray, necropsy, histopathology and ultrastructural pathology were carried out. At the same time, the seven newborn lambs(within 24 hours after birth) were inoculated intratracheally with (0.3ml/per lamb) cell-free filtration of pulmonary tumour tissue containing JSRV-NM strain from natural cases. And through the observation of eighteen-months long, the clinical pathology similarly as natural case of the four experimentally survived cases were examined. Additionaly, genomic DNA was prepared from the lung tumour tissues of two natural cases, fuor experimentally induced cases and six control sheep respectively, and in which detected the proviral DNA by PCR with a pair of primers designed by Primer Premier 5.0 software within the TM and LTR-U3 regions of the JSRV-NM strain sequences. Simultaneously, the dynamic changes of monocytes, lymphocytes and the subgrops of T lymphocytes and apoptosis of lymphocytes and monocytes of peripheral blood were examined both in natural cases and experimental cases by flow cytometry. The results showed that: (1) The two natural cases were both presented the classical clinical signs of SPA , the symptom named as“wheel barrow test”, higher heat and breath rate than unaffected sheep, anaemia, and, cloudy-shaped firm lesions in the lungs by X-ray. (2) The lungs were considerably enlarged and its surface and cut surface showed numerous firm, differently-sized and pinkish-gray nodules.Some cases were found that chronic adhesive pleurisy which made it difficult to remove the lungs from the thorax.White frothy fluid may be seen in the bronchi and bronchioli at necropsy. (3) Histologically, the secretory epithelial cells in the pulmonary alveoli and epithelial cells of the bronchioli proliferated and formed papillar form that project into the alveoli or bronchioli. Large numbers of epithelial cells accumulated in the alveoli adjacent to the neoplastic lesions.(4)更多还原