CELO病毒载体在人类和动物疾病控制上的应用

Characters in Molecular Biology of CELOV and Its Application as a Gene Vector

CELO病毒的DNA长43.8kb,具有末端倒转重复序列(ITR),基因结构与人腺病毒的比较,无可识别的E1、E3和E4区,但存在可替代的新读码框。2个fiber基因是病毒毒力基因,表达2个不同的蛋白,在病毒复制扩散中起作用,缺失fiber1导致柯萨奇病毒和腺病毒受体(CAR)的特异性转导作用消失,使CELO病毒只能感染禽类细胞,不能感染哺乳类动物细胞。在基因组的某些区段可以删除并插入外源基因不影响病毒复制。CELO病毒及其载体可在廉价的鸡胚中得到大量复制。CELO病毒的这些特性为其发展成新型基因工程栽体提供了条件。插入表达外源基因制备疫苗成为可能,新型的无病毒基因的载体也可以应用ITR及一些调控元件、包装信号共同构建形成。CELO病毒与人腺病毒属于同一属,CELO病毒作为基因工程载体有同样的特性,并且具有种属特异性和安全性,在动物基因工程疫苗的研制方面有特殊而广阔的研究和应用前景。

The complete DNA sequence of the avian adenovirus chicken embryo lethal orphan (CELO) virus (FAV-1) is 43,804bp in length, approximately 8kb longer than those of the human subgenus C adenovirus (Ad2 and Ad5).The CELO virus has inverted terminal repeats (ITRs).The conventional E1,E3, and E4 regions are no longer discernible, but there might be a protein of recognizable function in the left end of the CELO virus genome in place of the function of E regions. The fibers at each vertex of the virion are responsible for differences in virulence, and is essential for some stage in virus growth , assembly or spread. Fiberl is related to the character of CAR-dependent transduction behaviors. CELO virus, without fiberl, can enter chicken cells. A set of open reading frames can be deleted and allows the insertion of an expression cassette or foreign gene. The CELO vector is exceptionally stable, can be grown inexpensively in chicken embryos. The development of CELO vector bases on the characters of CELO virus. New-style vector with ITR and regulative element, packaging signal can be designed. CELO virus shares the common character with the human adenovirus but has super security, so the CELO vector as an interesting engineering vector will be a valuable tool in gene therapy and engineering vaccine development.