嗜麦芽寡养单胞菌胞外产物对斑点叉尾损伤的病理学研究
PATHOLOGICAL STUDIES ON CHANNEL CATFISH INDUCED BY EXTRACELLULAR PRODUCTS OF STENOTROPHOMONAS MALTOPHILIA
-
摘要: 采用硫酸铵盐析从嗜麦芽假单胞菌培养物中提取其胞外产物,通过腹腔注射方式,进行了嗜麦芽假单胞菌(P.maltophilia)胞外产物对斑点叉尾(Ictalurus punctatus)损伤的系统病理学研究。结果表明,嗜麦芽假单胞菌胞外产物具有较强的毒力,对斑点叉尾(42.5±4.4)g的半致死剂量(LD50)为3.21mg蛋白/kg体重。病鱼出现神经症状,腹部和下颌充血、出血,腹部膨大,腹腔内充满大量淡黄色或带血的腹水,胃肠道黏膜充血、出血,肠套叠,肝、脾、肾肿大等临床病变。组织学病变主要表现为全身多组织、器官水肿,出血、变性、坏死以及炎症反应,特别是脑、骨骼肌、肝、脾、肾和胃肠道的损伤较为严重。超微结构观察发现病鱼肝、脾、肾和骨骼肌等器官的细胞的超微结构均有较为严重的破坏,线粒体肿胀,嵴断裂或溶解消失,呈空囊状,内质网扩张,细胞核变形,染色质溶解或固缩;研究中还发现嗜麦芽假单胞菌胞外产物可致淋巴细胞凋亡,脾和肾间质内淋巴细胞均表现为细胞核染色质浓缩边移,或核固缩成一个或数个团块凝聚在核膜周边,形成凋亡小体。Abstract: Stenotrophomonas maltophiliam is an aerobic, nonfermentative, gram-negative bacterium ubiquitous in nature. It is a causative agent of the channel catfish (Ictalurus punctatus). S. maltophilia infection is capable of causing high morbidities and mortalities in channel catfish, it is considered to be the most significant factor affecting commercial catfish aquaculture. A stain of S. maltophilia, isolated from the diseased channel catfish in a fish farm in Sichuan Province, was identified by morphology, physiological and biochemical characteristics analysis, and 16srRNA gene sequence detection. In order to understand S. maltophilia pathogenetic mechanism, the pathology of channel catfish induced by extracellular products (ECPs) of S. maltophilia was studied. The ECPs of S. maltophilia was extracted with ammonium sulfate precipitation, and challenged with channel catfish by the intraperitoneal (i. p.) route. The test was conducted for 7d, with doses of 1.42mg/kg, 1.85 mg/kg, 2.40 mg/kg, 3.13 mg/kg, 4.07 mg/kg and 5.29 mg/kg body weight, respectively. The mortality was respectively 0.00%, 10.00%, 20.00%, 40.00%, 70.00% and 100.00%. The results showed that the ECPs of S. maltophilia had quite strong virulence to channel catfish, and the LD50 to channel catfish was about 3.21mg protein/kg body weight. Challenged fish showed neurosis, congestion and hemorrhage in the abdomen and lower jaw, distension of abdomen, yellowish or flooded fluid in the peritoneal cavity, congestion and hemorrhage in mucosa of gastrointestinal tract, intussusception in rectum, swelling in liver, kidney and spleen. Histopathological examination showed edema, hemorrhage, degeneration, necrosis and the inflammatory response in many organs; especially, serious lesions in brain, kidney, liver, gastrointestinal tract, spleen and skeletal muscle. The kidney showed edema, degeneration and necrosis in renal tubular epithelia, and with macrophages and neutrophi infiltration in the interstitial substance. Edema, vacuolar degeneration and necrosis were seen in liver cells. Epithelia of the gastrointestinal tract underwent degeneration and necrosis, while the lamina propria and tunica submucosa showed edema and infiltration with lymphocytes, macrophages and neutrophi. Congestion, hemorrhage and reduction of the lymphocytes were observed in spleen. Degeneration, necrosis and inflammatory cells infiltration appeared in skeletal muscles. Edema and neuronal shrinkage appeared in brain. Concentrated nucleolus, swelling mitochondria and dilatated endoplasmic reticulum were ultrastructurally observed in visceral organ (liver, spleen and kidney) cells. The lymphocytes of spleen and kidney underwent chromatin condensation and margination, forming the apoptotic bodies. These results indicated that the ECPs was an important pathogenic factor of S. maltophilia, which could induce apoptosis in the lymphocytes, miltiple organ damnification and death.
-
-
[1] Geng Y, Wang K Y, Chen D F, et al. Isolation, identificationand phylogenetic analysis of a pathogenic bacterium inchannel catfish [J]. Acta Microbiological Sinica, 2006, 46(4):649—652 [耿毅, 汪开毓, 陈德芳, 等. 斑点叉尾一株致病菌的分离鉴定及系统发育分析. 微生物学报, 2006,46(4): 649—652].
[2] Denton M, Kerr K G. Microbiological and clinical aspects ofinfection associated with Stenotrophomonas maltophilia [J].Clinical Microbiology Reviews, 1998, 11(1): 57—80.
[3] Singh N I, Swings I J, Devi R K T, et al. White stripe, a newdisease of rice caused by Stenotrophomonas maltophilia inIndia [J]. Indian Phytopathology, 2001, 54(2): 276.
[4] Johnson E H, Busaidy R, Hameed M S. An outbreak oflymphadenitis associated with Stenotrophomonas (Xanthomonas)maltophilia in Omani goats [J]. Journal of VeterinaryMedicine Series B, 2003, 50(2): 102—104.
[5] Zhang H J, Xie M Q, Zhang J F, et al. Cloning and sequenceing of 16S rRNA gene of Stenotrophomonas maltophiliafrom swine [J]. Chinese Journal of Veterinary Science andTechnology, 2004, 34(6): 3—5 [张浩吉, 谢明权, 张健騑,等. 猪源嗜麦芽窄食单胞菌16 S rRNA 基因的克隆和序列分析. 中国兽医科技, 2004, 34(6): 3—5].
[6] Harris N B, Rogers D G. Septicemia associated with Stenotrophomonasmaltophilia in a West African dwarf crocodile(Osteolaemus tetraspis subsp. tetraspis)[J]. Journal of VeterinaryDiagnostic Investigation, 2001, 13(3): 255—258.
[7] Huang B, Chen S F, Chen Y. Study on cystis disease of Cistoclemmysflaciomarginata [J]. Freshwater Fisheries, 2002,32(5): 44—46 [黄斌, 陈世锋, 陈勇. 黄缘闭壳龟囊肿病的研究. 淡水渔业, 2002, 32(5): 44—46].
[8] Zhou Y C, Zhu W H, Zhang B, et al. Isolation and preventionof the pathogen causing large scale death on Trachinotusovatus [J]. Marine Sciences, 2001, 25(4): 40—44 [周永灿,朱伟华, 张本, 等. 卵形鲳大规模死亡的病原及其防治.海洋科学, 2001, 25(4): 40—44].
[9] Li J N, Jiang D F, Li L, et al. Coding identification on 28stains pathogenic bacteria of aquatic animal [J]. ReservoirFisheries, 2004, 24(2): 62—64 [李槿年, 江定丰, 李琳, 等.28 株水产动物致病菌的编码鉴定. 水利渔业, 2004, 24(2):62—64].
[10] Chen D F, Wang K Y, Geng Y, et al. Characteristics andpathogenicity of the extracellular products of Stenotrophomonasmaltophilia from channel catfish [J]. Reservoir Fisheries,2008, 28(1): 99—101 [陈德芳, 汪开毓, 耿毅, 等.斑点叉尾源嗜麦芽寡养单胞菌胞外产物的生物学特性与致病性研究. 水利渔业, 2008, 28(1): 99—101].
[11] Shi C B, Hu X F, Chen X G, et al. Characteristics of theExtracellular Products of two pathogenic vibrio harveyistrains [J]. Acta Hydrobiological Sinica, 2007, 31(1): 83—87[石存斌, 胡学峰, 陈献稿, 等. 两株致病性哈维氏弧菌胞外产物的特性分析. 水生生物学报, 2007, 31(1): 83—87].
[12] Inamura H, Muroga K, Nakai T. Toxicity of extracellularproducts of Vibrio anguillarum [J]. Fish Pathology, 1984,19(2): 89—96.
[13] Rodriguez L A, Ellis A E. Purification and characterization ofan extracellular metalloprotease, serine protease and haemolysinof Aeromonas hydrophila strain B32: all are lethal forfish [J]. Microbial Pathogenesis, 1992, 13(1): 17—24.
[14] Xu H S, Shu M A, Zhan X A, et al. Identification of Vibrioparahemolyticus isolated from cultured Eriocheir sinensisand pathogenicity of its extracellular products [J]. Journal ofFisheries of China, 2002, 26(4): 357—362 [徐海圣, 舒妙安,占秀安, 等. 养殖河蟹弧菌病病原菌分离鉴定及其胞外产物的致病性. 水产学报, 2002, 26(4): 357—362].
[15] Li Y Y, Li J N, Yu W Y, et al. Study on the cytotoxicity andpathogenicity of the extracellular Products of vibrio minicusfrom Eriocheir sinensis [J]. Reservoir Fisheries, 2004, 24(5):78—80 [李玉英, 李槿年, 余为一, 等. 蟹源拟态弧菌胞外产物的细胞毒性和致病性初步研究. 水利渔业, 2004,24(5): 78—80].
[16] Jin S, Zheng T L, Wang G L, et al. Pathogenicity of ExtracellularProducts of Vibrio alginolyticus to Great YellowCroaker, Psedosciaena crocea [J]. Chinese Journal of VeterinaryScience, 2004, 24(5): 439—441 [金珊, 郑天伦, 王国良, 等. 溶藻弧菌胞外产物对大黄鱼的致病性. 中国兽医学报, 2004, 24(5): 439—441].
[17] Ge Y, Chen H Q, Lu C P. Cytotoxity and Pathogenicity in theMice and Fish of Extraceilular Products of Edwardsiellatarda [J]. Chin J Vet Sci, 2000, 20(1): 34—37 [葛艳, 陈怀青, 陆承平. 迟缓爱德华氏菌胞外产物的细胞毒性与动物致病性. 中国兽医学报, 2000, 20(1): 34—37].
[18] Wang K Y, Geng Y, Chen D F, et al. Isolation of pathogenand observation on pathology of acute epidemic disease inchannel catfish, Ictalunes punctatus [J]. Journal of FisherySciences of China, 2007, 14(3): 457—465 [汪开毓, 耿毅,陈德芳, 等. 斑点叉尾急性流行性传染病的病原分离与病理学观察. 中国水产科学, 2007, 14(3): 457—465].
[19] Kerr J, Wyllie R, Curie A H. Apoptosis: A basic biologicalphenomenon with wide ranging implications in tissue kinetic[J]. British Journal of Cancer, 1972, 26: 239—257.
[20] Berhammer F A, Hochegger K, Froschl G, et al. Chromatincondensation during apoptosis is accompanied by degradationof lamin A + B, without enhanced activation of cdc2kinase [J]. The Journal of Cell Biology, 1994, 126: 827—883.
[21] Shi B, Girolamiu D, He J, et al. Apoptosis induced by HIV-1infection of the central nervous system [J]. Journal of ClinicalInvestigation, 1996, 98(9): 1979—1990.
[22] Zhang C X, Wang J, Su Y Q. Studies on pathogenesis ofextracellular products from pathogenetic bacteria in Penaeusmonodon Fabrivius [J]. Acta Oceanological Sinica, 2000,22(5): 94—99 [张朝霞, 王军, 苏永全. 斑节对虾病原菌胞外产物的致病性研究. 海洋学报, 2000, 22(5): 94—99].
计量
- 文章访问数: 1144
- HTML全文浏览量: 5
- PDF下载量: 656
下载: