泰氏锥虫抗原制备及实验室诊断研究

应用体外培养的泰氏锥虫制备可溶性抗原Ⅰ、抗原Ⅱ和代谢抗原.经测定,其蛋白含量每毫升分别为6.5mg、7.4mg和7.1mg.薄层等电聚焦电泳测定结果表明,抗原Ⅰ出现22条区带,抗原Ⅱ21条区带,代谢抗原28条区带,对照的伊氏锥虫琼脂免疫扩散抗原14条区带.经分析,泰氏锥虫抗原和伊氏锥虫抗原有4条区带在同一迁移率上.琼脂免疫扩散反应中,3种泰氏锥虫抗原均与相应免疫兔血清发生沉淀反应,抗原Ⅰ出现1条致密沉淀线,抗原Ⅱ和代谢抗原出现2～3条沉淀线,抗原效价为1:4～16.免疫电泳显示了类似的结果,抗原Ⅰ与免疫兔血清出现1条弧形沉淀线,抗原Ⅱ和代谢抗原与免疫兔血清出现了3条弧形沉淀线.间接血凝试验结果表明,泰氏锥虫自然感染牛血清效价为1:20～40,免疫兔血清为1:1280～5120.所制泰氏锥虫抗原对伊氏锥虫和媾疫锥虫血清也能很好地发生交叉反应,3份伊氏锥虫病马血清和3份伊氏锥虫人工感染兔血清血凝效价分别为1:10～40和1:8～1024;5份媾疫马血清有4份血凝效价为1:20～320.4份环形泰勒虫病牛血清均为阴性.     

锥虫不同分离株克隆及其等电聚焦分析

将两个伊氏锥虫及一个马媾疫锥虫的不同分离株分别接种用球磷酰胺处理的小鼠，获得五个克隆，用等电聚焦比较其蛋白质差异。结果表明，三个分离株之间有明显区别；马媾疫锥虫显著不同于伊氏锥虫；分离株不同克隆间区别较小，其中广东水牛株两克隆间带型相同，安徽水牛两克隆间带型略有区别。证明伊氏锥虫克隆间变异较小，锥虫不同分离株间变异较大，马媾疫锥虫与伊氏锥虫之间变异最大。     

应用质粒PTK探针鉴定锥虫的初步研究

用^32P标记质粒探针PTK1、PTK1.1和PTK1．2，对12株中国伊氏锥虫的斑点杂交试验显示，3个探针均能与8株具有正常动基体的伊氏锥虫杂交，而不与其余4株异常动基体伊氏锥虫杂交，对正常动基体株的敏感度为10^2虫体。探针PTK1亦能与马媾疫锥虫杂交，敏感度为10^2个虫体。但PTK1与布氏锥虫仅发生微弱的杂交反应．敏感度为10^5个虫体。试验表明伊氏锥虫株之间的kDNA微环是同源的，伊氏锥虫与马媾疫锥虫和布氏锥虫的kDNA微环存在着共同序列。     

伊氏锥虫、马媾疫锥虫、布氏锥虫、刚果锥虫的18S rDNA部分序列测定与系统发育关系

对伊氏锥虫（Trypanosoma evansi）：新疆株（XJCA）、湖北株（HBM）、云南株（YNB）、广东株（GDB2）；马媾疫锥虫（Trypanosoma equiperdum）、布氏锥虫（Trypanosoma brucei）、刚果锥虫（Trypanosoma congolense）提取基因组DNA，根据已报道的伊氏锥虫株18SrDNA基因序列设计合成引物，用PCR扩增了锥虫虫株基因组DNA,伊氏锥虫新疆株、湖北株、云南株、广东株、布氏锥虫、刚果锥虫均为373bp的片段；马媾疫锥虫为372bp的片段，PCR产物经电泳鉴定后用试剂盒回收纯化，纯化后PCR产物经连接、转化后测序，将测得的序列用DNAMAN软件分析并与国外已发表的相应序列进行了同源性比较，并绘制了系统发育进化树。结果与国外AJ009153、AJ223564、D89527株同源性达到99％～100％，与另外11株同源性75％。本研究为锥虫分子流行病学研究及分类研究打下基础。     

锥虫长期超低温保藏方法的研究

作者观测不同保护剂、稀释液、ＰＨ值、降温方法、复苏温度、冻融次数、液相气相交替以及解冻后在普通冰瓶中存放时间对伊氏锥虫浙江虫浙江虫株的感染性及致病力的影响。在此试验基础上，又对伊氏锥虫的６个不同虫株、媾疫锥虫、铡果锥虫、布氏锥虫等４个种的９个早株，进行了超低温保藏试验和长期保藏效果观察。已测定的有效保藏期伊氏锥虫达５７４－３２００天，媾疫锥虫达２８６６天，则果锥虫达７６３天，布氏锥虫７８３天。通过     

伊氏锥虫补反抗原与媾疫锥虫补反抗原诊断马媾疫病的比较

<正> 用补体结合反应诊断马媾疫,所用的抗原有伊氏锥虫补反抗原和媾疫锥虫补反抗原,为了探讨两种抗原对马媾疫的检出率,我们做了对比试验,现将试验情况分述如下: 试验抗原一、伊氏锥虫补反抗原,成都兽医生物药品制造厂出品。二、媾疫锥虫补反抗原,陕西省兽医研究所制造。     

媾疫锥虫、伊氏锥虫差异抗原的分离鉴定

以50％饱和硫酸铵沉淀的兔抗伊氏锥虫高免血清球蛋白制备琼脂糖-4B免疫吸附柱,对马媾疫锥虫超声全虫可溶性抗原进行反亲和层析免疫吸附。当抗原量在抗体吸附范围内时,最先洗脱下来的成分即为媾疫锥虫特异性抗原(差异抗原)。该抗原与媾疫锥虫血清抗体反应较强,与伊氏锥虫血清抗体反应较弱,经SDS-PAGE检测,其为分子量大于68000的大分子蛋白。     

建议将伊氏锥虫和马媾疫锥虫更名为布氏锥虫伊氏亚种和马媾疫亚种

伊氏锥虫(TrypanosomaevansiBalbiani,1888)和马媾疫锥虫(T.(T)equiperdum,Doflein,1901)是我国广泛存在的两种对家畜有致病性的锥虫。在分类上,它们均属于原生动物亚界肉足鞭毛亚门动鞭毛纲动基     

论马媾疫锥虫与伊氏锥虫分类性状之异同

马媾疫锥虫(Trypanosoma equiperdum Doflein,1901)1894年在阿尔及利亚发现,是马属动物通过交配经生殖器粘膜感染的一种慢性原虫病的病原。伊氏锥虫[T.evansi(Steel,1885)Balbiani 1888]1880年发现于印度的马和骆驼,是由吸血昆虫虻类等传播的马、牛和骆驼锥虫病的病原。两种锥虫同属锥虫科锥虫属布氏组。迄今为止,各种教材和专著中,都认为这两种锥虫在形态上无区别,但其生物学特性则彼此不同。本文援引有关文献资料,结合笔者的第一手材料,对马媾疫锥虫与伊氏锥虫分类性状诸问题,进行如下对比性分析。     

伊氏锥虫同工酶、蛋白质和抗原组分的比较研究

本文采用生化技术对八个中国伊氏锥虫株及一个布氏锥虫株的同工酶、蛋白质和抗原组分进行比较研究。根据同工酶电泳结果,可将伊氏锥虫和与其形态上不能区分的布氏锥虫区别开来,亦可将伊氏锥虫分为两个酶株群(Z1、Z2)。根据SDS-聚丙烯酰胺凝胶电泳、等电聚焦电泳和免疫印迹试验的结果,可将酶株群Z1分成五个不同多肽群(株)。本研究结果表明,中国伊氏锥虫遗传变异程度较低,是一个相对稳定的种群。     

The expression of RoTat 1.2 variable surface glycoprotein (VSG) in Trypanosoma evansi and T. equiperdum

In order to define whether the variable antigenic type RoTat 1.2 is restricted to Trypansoma evansi and could be used as antigen in serological tests to differentiate T. evansi from Trypansoma equiperdum, the appearance of RoTat 1.2-specific antibodies in rabbits, experimentally infected with T. evansi and T. equiperdum, respectively, was analyzed. Ten strains of T. evansi and 11 strains of T. equiperdum originating from Asia, Europe, Africa and Latin America were tested. Rabbit pre-infection sera and sera of days 7, 14, 25, 35 post-infection (p.i.) were analyzed for the presence of antibodies reactive with RoTat 1.2 in immune trypanolysis, ELISA/T. evansi and CATT/T. evansi. Within the duration of the infection (maximum 35 days), all T. evansi as well as 9 out of 11 T. equiperdum infected rabbits became positive in all these tests. The rabbits infected with T. equiperdum OVI (South Africa) and BoTat 1.1 (Morocco) remained negative in the immune trypanolysis test although the latter rabbit became positive in the CATT/T. evansi and ELISA/T. evansi. On the contrary, both rabbits were positive in immune trypanolysis when tested against their respective infecting population. From these data, we conclude that most T. equiperdum strains express isoVATs of RoTat 1.2. This explains, in part, why antibody tests based on T. evansi RoTat 1.2 cannot reliably distinguish between infections caused by T. evansi and those caused by T. equiperdum unless it can be proven that most described T. equiperdum are actually misclassified T. evansi.     

伊氏锥虫和布氏锥虫动基体DNA酶切电泳比较

限制性内切酶ＭｂｏＩ，ＤｄｅＩ，Ｈｉｎｆｉ和ＴａｑＩ对布氏锥虫ＫＤＮＡ进行酶切后，电泳中均显示出多条ＤＮＡ区带，其总Ｋｂ数约等于２０ｋｂ，而各限制酶对伊氏锥虫ＫＮＤＡ消化后均显示出１至２条区带，总和约１ｋｂ明显区别于布氏锥虫。     

Establishment of a panel of reference Trypanosoma evansi and Trypanosoma equiperdum strains for drug screening

The animal pathogenic protozoan, Trypanosoma evansi, leads to a wasting disease in equines, cattle and camels, commonly known as Surra. It is extensively distributed geographically with a wide range of mammalian hosts and causes great economical loss. Trypanosoma equiperdum causes a venereal disease called Dourine in horses and donkeys. Chemotherapy appears to be the most effective form of control for T. evansi, whereas infections caused by T. equiperdum are considered incurable. Due to emerging drug resistance, efficient control of T. evansi is severely threatened, emphasising the urgent need to find new alternative drugs. A drug profile for a panel of T. evansi and T. equiperdum strains has been established for the four standard drugs currently used in treatment. The (3)H-hypoxanthine incorporation assay was used to obtain 50% inhibitory concentration (IC(50)) values for each standard drug against the various strains. The results indicate the presence (and in some cases, the emergence) of drug resistance in several strains. This panel of characterised strains with known drug sensitivities and resistances will be of great value for the screening of new active compounds, in comparison with the four standard drugs currently available.     

伊氏锥虫病原性受体纯化的研究

以伊氏锥虫表膜蛋白做配基辛和层析，从小鼠淋巴细胞、巨噬细胞和肾上皮细胞上分别纯化出了分子量相同的一种蛋白质。该蛋白经ＰＡＧＥ电泳分析，是表观分子量约为１２０．１ｋＤ的单一蛋白质，在ＳＤＳ－ＰＡＧＥ电泳系统中显示为分子量分别是７５．１ｋＤ和３５．６ｋＤ的两种蛋白质，从淋巴细胞上纯化出来的该蛋白质具有免疫球蛋白的抗原性，但来源于肾上皮细胞的物质却无此活性。用淋巴细胞膜上的该受体做阻断试验发现，某一浓度下的该受体不仅不能阻断，反而会促进固定的小鼠细胞与锥虫的粘附结合。     

水牛梭形住肉孢子虫抗原的薄层等电聚焦行为分析

应用薄层聚丙烯酰胺等电聚焦电泳（ＩＦＥ）对水牛梭形住肉孢子虫（Ｓａｒｃｏｃｙｓｔｉｓｆｕｓｉｆｏｒｍｉｓ）抗原进行了分析。结果表明，经ＳｅｐｈａｄｅｘＧ－１００纯化的包囊抗原在电泳图谱上显示３条相距较近的带，等电点分别为６．３０，６．４５，６．６５；缓殖子纯化抗原仅出现１条带，等电点为６．４０     

Genetic variability of Trypanosoma evansi isolates detected by inter-simple sequence repeat anchored-PCR and microsatellite

Studies on genetic variability in Trypanosoma evansi have been limited by a lack of high-resolution techniques. In this study, we have investigated the use of inter-simple sequence repeats (ISSR) and microsatellites in revealing polymorphism among T. evansi isolates. Twelve ISSR primers and five microsatellite loci were used to generate polymorphic bands and alleles, respectively, to investigate the genetic variability among T. evansi isolates from Africa and Asia. Seven of the twelve ISSR primers showed variability between isolates with a total of 71 fragments of which 49(69%) were polymorphic. Microsatellite analysis revealed a total of 60 alleles. On average the ISSR markers revealed a higher genetic diversity (23%) than microsatellites (21.1%). The two techniques showed a strong agreement of r=0.95 for Dice and r=0.91 for Jaccard indices in estimating the genetic distances between isolates. The distance UPGMA tree revealed two major clusters of T. evansi which correlate with the minicircle classification of subtype A and B. The cophenetic correlation coefficient between Dice and Jaccard based matrices were r=0.79 for microsatellites and r=0.73 for ISSR indicating a strong agreement between dendrograms. The results suggest that both ISSR and microsatellites markers are useful in detecting genetic variability within T. evansi.     

不同宿主源棘球蚴包囊液抗原的SDS—PAGE分析

本文利用ＳＤＳ－ＰＡＧＥ对不同宿主源棘球蚴囊液抗原的多肽组成进行了分析和比较,旨在为免疫诊断抗原的分离、鉴定和纯化奠定基础,为细粒棘球绦虫种内变异和株的鉴定提供参考指标。结果表明,在还原条件下,绵羊棘球蚴囊液抗原共有多肽带１９条,其中６６和５９ＫＤ多肽带为主带,４０、３４．５、３３、２４．５和１４ＫＤ多肽带次之。牛源囊液抗原共有多肽带１２条,６６和５９ＫＤ多肽带也为主带,２４．５ＫＤ多肽带次之。人源囊液抗原共有多肽带１３条,６６、４０、２０．５和１４ＫＤ多肽带为主带,５９ＫＤ多肽带近于缺乏,分子量在５９和２４ＫＤ之间的带明显偏少,而７１、６９、６８和２０．５ＫＤ多肽带为自身特有。３种不同宿主源棘球蚴囊液抗原其多肽组成均很复杂,羊、牛源囊液抗原的ＳＤＳ－ＰＡＧＥ图谱较相似,而人源与此差异明显。初步认为绵羊和牛源囊液抗原在免疫诊断中具有可替代性。