中国农业科学 ›› 2008, Vol. 41 ›› Issue (2): 576-580 .doi: 10.3864/j.issn.0578-1752.2008.02.036

• 兽医 • 上一篇    下一篇

鸡新城疫壳聚糖微球疫苗的制备及免疫效果研究

徐怀英,秦卓明,王友令,贾 强,翟荣玲   

  1. 山东省农业科学院家禽研究所
  • 收稿日期:2006-08-08 修回日期:1900-01-01 出版日期:2008-02-10 发布日期:2008-02-10
  • 通讯作者: 秦卓明

Genotypes of the extend spectrumβ-lactamase(ESBLs) produced by the shigella isolated from the fowl

  

  1. 山东省农业科学院家禽研究所
  • Received:2006-08-08 Revised:1900-01-01 Online:2008-02-10 Published:2008-02-10

摘要: 【目的】新城疫是禽类的一种急性、高度接触性传染病,是危害养禽业的首要疫病。疫苗免疫是控制该病的首选方法,但目前常用的弱毒活疫苗和灭活疫苗具有各自的缺点,在实际应用中具有一定的局限性。故本研究拟制备新城疫壳聚糖微球疫苗,以弥补弱毒活疫苗和灭活疫苗的不足。【方法】利用壳聚糖为囊材,新城疫病毒液为芯材,戊二醛为交联剂,选择适当的乳化体系,制备出粒径小、分散性好的新城疫微球疫苗。将新城疫壳聚糖微球疫苗与LaSota活疫苗和新城疫灭活疫苗分别免疫SPF鸡,利用MTT试验和血清IgG HI试验,分别检测不同疫苗免疫后的细胞免疫和体液免疫水平,并在血清抗体水平为3log2时进行攻毒试验。【结果】制备的新城疫壳聚糖微球疫苗平均粒径为5.83 μm,均匀度较好,免疫试验鸡后可刺激机体产生较强的细胞免疫和体液免疫,与另外两组数据比较均有显著差异;且微球疫苗免疫组对强毒株的攻毒产生了较好的保护。【结论】新城疫壳聚糖微球兼有弱毒活疫苗和灭活疫苗的优点,具有较好的免疫保护效果,是一种具有广阔应用前景的新型疫苗。

关键词: 新城疫, 壳聚糖, 微球疫苗

Abstract: 【Objective】 The genotypes of five ESBLs-producing shigella flexneri clinical isolates and a standard ESBLs-producing shigella flexneri induced by Ceftifur were detected ,at the same time ,we studied the molecular involvement mechanism of the shigella flexneri ESBLs production.【Method】The standard shigella flexner was induced by Ceftifur with 0.5MIC concentration and detected βlactamase every ten times.After induced shigella flexner had produced ESBLs, the plasmides of it and 5 ESBLs-producing clinical shigella flexneri were amplified by PCR using the primers of TEM,SHV, CTX-M,respectively, their PCR products were cloned and then the cloned fragments were sequenced. The nucleotide sequence obtained were analyzed using DNASTAR software.The search for homologous sequences was done in the GenBank database using FAST software through the Internet. 【Results】 There were the same TEM- type and SHV- type sequences in the plasmids of the five shigella flexneri clinical isolates.The sequence of the TEM-type was characterized by two nucleotide mutations (G157A,C409T) compared with the sequence of AY903309(TEM-116).The mutation of nucleotide 409 was aslient mutation,the mutation of nucleotide 157 leaded to the mutation of amino acid( Gly53Ser) and the mutation didn't exist in the published ESBLs sequences.Therefore, the TEM-type was a new genotype,named TEM-1V type.The sequence of SHV-type was the same as that of the AY826418(SHV-12), therefore the obtained sequence was the SHV-12 type. For the standard shigella flexneri,when it was induced to the tenth times by Ceftiofur, its gene sequence of the produced β-lactamase was the TEM-1 type, when induced to the fifth times,the gene sequence of the produced ESBLs was the TEM-1V type. 【Conclusion】(1)The shigella flexneri clinical isolates harbored TEM-1V type and SHV-12 type ESBLs.(2) when it was induced to the tenth times by Ceftiofur, the standard shigella flexneri's gene sequence of the produced β-lactamase was the TEM-1 type, when induced to the fifth times,the gene sequence of the produced ESBLs was the TEM-1V type.