兔脑炎原虫引起的脑组织细胞凋亡

为了调查兔脑炎原虫引起脑组织细胞的凋亡情况,本研究用特殊染色、TUNEL染色、凋亡蛋白免疫组化染色和Western blot,对40只家兔的脑组织进行了详细研究。结果表明,病兔的脑组织中均检出了肉芽肿和脑炎原虫。脑炎原虫所引起的脑细胞凋亡主要发生于脑血管的内皮细胞、星形胶质细胞、巨噬细胞和上皮样细胞,其次为病变所累及的神经细胞。用TUNEL的免疫酶-荧光染色和抗凋亡蛋白的免疫组化染色,凋亡细胞均呈强阳性反应,被染成棕褐色。对脑组织蛋白提取物进行Western blot检测,病兔脑组织中P~(53)、Bcl-2、Bax和c-Myc凋亡基因蛋白表达量明显高于对照兔,差异非常显著(P0.01)。结果表明,兔脑炎原虫在脑组织细胞内寄生时可以引起细胞凋亡。     

兔脑炎原虫引起脑细胞凋亡与血脑屏障破坏的关系

为了研究兔脑炎原虫如何破坏血脑屏障,侵入脑组织并引起脑肉芽肿形成,本试验采用IG染色、MGP染色,TUNEL染色和anti-GFAP染色等方法对26只有典型脑炎原虫病神经症状的病兔和10只健康兔的脑组织进行了详细研究。结果显示:病兔大脑皮质有少部分锥体细胞、血管内皮细胞及星形胶质细胞发生不同程度的凋亡。病损的血管旁有时检出兔脑炎原虫集落,附近的脑组织有巨噬细胞和小胶质细胞聚集形成的细胞性肉芽肿。用特殊染色可在血管内皮细胞、单核细胞和巨噬细胞中检出大量脑炎原虫和集虫泡。大量星形胶质细胞在病损的脑组织部位增生,包绕在聚集的巨噬细胞和小胶质细胞周围形成了肉芽肿。其粗大的足突在血管周围形成了厚层血脑屏障。总之,兔脑炎原虫通过导致血管内皮细胞和星形胶质细胞凋亡的方式而破坏了血脑屏障;通过侵入血管内皮细胞和单核细胞的方式进入脑组织,引起脑损伤。     

兔脑炎原虫病肾脏病变的分型及快速诊断

兔脑炎原虫病肾脏病变的分型及快速诊断潘耀谦，刘纯杰，崔龙波，苏维萍（吉林长春解放军农牧大学，１３００６２）肾脏是脑炎原虫侵害的主要靶器官之一，对脑炎原虫病的病理解剖学诊断具有重要价值。据报道￣［１－６］，脑炎原虫所致的肾脏病变是间质性肾炎，但有关肾脏...     

屠宰兔脑炎原虫病的快速检验

脑炎原虫病是一种人畜共患的寄生虫病,其病原为小孢子虫目(Microsporidia)、微粒子虫科(Nosematae)的兔脑炎原虫(En-cephalitozoon Cuniculi)。病原侵害的主要靶器官为脑组织和肾脏。据报道脑炎原虫的感染范围较广,可使鼠、兔、犬、猫、猴、     

自然感染兔脑炎原虫獭兔肾上皮细胞凋亡的研究

运用透射电镜术、原位末端标记技术(TUNEL)和流式细胞术对11只自然感染兔脑炎原虫獭兔的肾脏进行了细胞凋亡研究，5只健康长耳白兔用作对照。结果表明．凋亡细胞多见于远曲小管和集合管的上皮细胞。用透射电镜观察，初期的凋亡细胞，其细胞核的染色质高度凝集，边缘化，粗面内质网增多、扩张呈泡状；后期的凋亡细胞，其细胞质浓缩．细胞膜起泡，细胞核分裂成块状，最后形成膜包裹的凋亡小体。TUNEL法检测，病变轻微的细胞，胞核微缩，胞膜增厚；病变严重的细胞，其胞核体积明显缩小，胞膜皱缩，最后形成膜包裹的凋亡小体。流式细胞术检测，病兔可呈现明显的亚“G1”峰，凋亡细胞百分比与对照兔相比差异极显著(P=0．01)，且病兔。肾细胞的周期也有所改变。结果表明，3种方法检测的病兔肾上皮细胞凋亡数均高于对照免。     

脑炎原虫病兔免疫器官的病理形态学观察

研究脑炎原虫病兔外周免疫器官的形态学变化,采集20只病兔和12只对照兔的淋巴结、脾脏和圆小囊,通过临床检查,病理剖检,病理切片的HE染色、吉姆萨染色和免疫组织化学染色进行了比较观察。结果表明病兔淋巴结内的淋巴小结数量增多,生发中心明显,髓索增粗,副皮质区增宽。脾脏的脾小结增多,变大,具有明显的生发中心,边缘区明显增宽,动脉周围淋巴鞘明显变大,聚集大量淋巴细胞。圆小囊的淋巴小结增大,数量增多,生发中心明显,淋巴小结周围弥散大量淋巴细胞。通过α-ANAE和sABC染色,在淋巴结、脾脏和圆小囊中均可检出大量T细胞、巨噬细胞和IgG阳性细胞。据此认为患脑炎原虫病时,病兔的体液免疫和细胞免疫均增强,但以细胞免疫反应更强。     

兔脑炎原虫病肾脏病变的病理形态学观察

对97只患脑炎原虫病獭兔的肾脏病变做了系统的病理形态学研究.眼观,可将肾脏病变分为三型:皱缩型、凹陷型和斑点型;镜检,依结缔组织增生的数量、部位和肾组织结构的不同改变而分为贯通型、局灶型和肉芽肿型.     

兔脑炎原虫的超微形态与发育

用电镜连续７代动态地观察了培养细胞中兔脑炎原虫的超微结构与发育状态。脑炎原虫含有细胞核，但无线粒体、内质网和高尔基复合体等细胞器，其表面有几根极丝。脑炎原虫在培养细胞中除二分裂增殖外，还有裂体增殖和配体增殖。由于脑炎原虫有３种增殖方式，故在光学显微镜下呈多形态结构。     

Microsporidia (Encephalitozoon cuniculi) in wild rabbits in Australia

Objective To determine the prevalence of infection with Encephalitozoon cuniculi i n wild rabbit populations in Western Australia, and to isolate the organism from seropositive rabbits.
Design Serological screening of wild and clinically affected domestic rabbit populations.
Sample population Eighty-one wild rabbits from southwestern Western Australia and 29 laboratory rabbits.
Procedure Indirect immunofluorescence antibody technique and in-vitro amplification of parasite isolates in fibroblast cultures.
Results Of the 81 wild rabbits and 29 laboratory rabbits, 20 and 22 respectively, had antibodies to E cuniculi . E cuniculi from the urine of one seropositive laboratory rabbit and from brain and kidney tissues of eight and five seropositive laboratory and wild rabbits respectively were isolated in fibroblast cultures.
Conclusion E cuniculi infection has been shown for the first time to be prevalent in wild rabbits in Australia. Techniques have been developed for the isolation and culture of the causative agent. Comparative studies can now be undertaken to determine risk factors for clinical disease in domestic rabbits and the relationship among E cuniculi isolates from wild and domestic rabbits.     

兔脑炎原虫的分离与鉴定

3只临床表现斜颈、麻痹和打滚的病兔,经病理组织学检查诊断为脑炎原虫病.取其脑组织制成乳剂,接种于兔肾细胞、Vero细胞、猫肾细胞和兔脉络丛细胞.用前3种细胞均分离出原虫.该虫体表现为多种形态,呈杆状、圆形或卵圆形;Gram染色呈阳性,Goodpasture氏染色呈红色.用20%H_2O_2处理虫体,在相差显微镜下见到虫体极丝的伸展.通过虫体的形态学、染色特征和极丝的突出实验,鉴定该虫体为脑炎原虫.兔肾细胞、Vero细胞和猫肾细胞的感染率分别为40%、40%和5%,而在兔脉络丛细胞原代培养物中未检查到虫体.     

细胞培养的脑炎原虫感染家兔实验

用在体外连续培养１０代的兔脑炎原虫，接种于１２只家兔，动态地观察了脑炎原虫对家免的感染情况。实验发现，肾脏产生的病变明显早于大脑，即感染３周后，用Ｇｒａｍ＇ｓ和Ｇｏｏｄｐａｓｔｕｒｅ＇ｓ染色，即可在髓袢和远曲小管内脱落的上皮细胞中发现兔脑炎原虫。６周后即可见到间质性肾炎变化，而脑组织于感染９～１２周时才见有细胞性肉芽肿的形成；脑炎原虫具有较强的抗原性，即在感染３周后，血液中的抗体含量足以进行诊断。     

阿苯达唑对自发性兔脑炎原虫病的治疗

为了有效地治疗兔脑炎原虫病,本研究根据脑炎原虫的生物学特点和对组织损伤的特征选用阿苯达唑进行了治疗试验。将28只3～4月龄隐性感染的獭兔,随机分为对照组和治疗组进行试验。治疗组按30mg／kg剂量（首次给药量为50mg／kg）,每隔12h给药1次,连续用药10d,停药1周为1个治疗期,共治疗3个疗程。对照组按正常饲养。每1疗程之后,均采血和尿液进行ELISA检测和尿沉渣虫体检查。结果,治疗组的病兔用阿苯达唑治疗3个疗程后,ELISA检测的D值均低于标准值（〈0．044）,即抗脑炎原虫血清抗体呈阴性反应,从尿沉渣中也不能检出虫体。而对照组病免的D值则大大高于正常值．从尿沉渣中均易检出虫,并有1只对照兔出现典型的神经症状,剖检后从脑组织中检出脑炎原虫性肉芽肿。经方差分析,2组间差异非常显著（P〈0．01）。试验证明,阿苯达唑对兔脑炎原虫有良好治疗作用,用药的时机以脑炎原虫还未进入脑组织时最合适,用药的剂量一定要保持有效的杀虫浓度。     

Immunohistochemical identification of Encephalitozoon cuniculi in phacoclastic uveitis in four rabbits

PURPOSE: Encephalitozoon cuniculi is a microsporidium with a wide range of mammalian hosts. In rabbits it can be responsible for cataract and lens-induced uveitis (LIU). The aim of this study was to provide specific immunohistochemical demonstration and localization of E. cuniculi within the eye, in rabbits with LIU. MATERIAL AND METHODS: Four rabbits were presented with a white mass in the eye and iris discoloration. Complete ophthalmic examinations were performed and a presumptive diagnosis of LIU was made in all cases. Initial therapy with a topical steroid, atropine and systemic enrofloxacin was instituted while serologic (IFA or ICA tests) and cytologic lab results were pending. The final outcome in all cases was enucleation. Routine histology and immunohistochemistry (ABC method) with an antiserum anti-Encephalitozoon cuniculi were performed. RESULTS: Indirect immunofluorescence performed on one rabbit serum expressed a titer of 1 : 32; carbon immunoassay on the serum of the other three rabbits expressed a titer of 1 : 5120 in one, and a titer of 1 : 2560 in the other two cases. Histologically, an intraocular, locally extensive pyogranulomatous infiltration that partially filled the posterior chamber, encasing a wide anterior lens capsule break, was detected in all cases. Immunohistochemically, spores reacting with anti-Encephalitozoon cuniculi antiserum were present in all specimens, occasionally within macrophages and lens epithelial cells. CONCLUSION: Detection of E. cuniculi in rabbits with phacoclastic uveitis has been investigated in the past with different methods. Based on our results, we suggest that immunohistochemistry should be regarded as a useful tool both for specific demonstration of E. cuniculi and for its localization within tissues.