Clone and Expression of Loop1 and Loop2 Gene of Hexonof Infectious Canine Hepatitis Virus / 中国生物工程杂志

ABSTRACT

The mainly antigenic sites for the adenovirus neutraliation are present on Loop1 and Loop2 of hexon.Majority research were focus in the human adenovirus.Little was known on infectious canine hepatitis virus (ICHV), which was also called canine adenovirus typeⅠ.Here,ICHV (the isolated strain) DNA was isolated and purified from the cultured MDCK cells.The Loop1 and Loop2 fragments were amplified by polymerase chain reaction(PCR) method,and then was connected by ligase T4.The target fragment was then connected with vector pET28a.The nucleotide sequence ecoding Loop1 and Loop2 was determined.The nucleotide sequence identity of Loop1 region between the isolated strain and CLL, RI261 and Toronto A26/61 strains is 100%, 100% and 83.8%, and the nucleotide sequence identity of Loop2 region between the isolated strain and CLL, RI261 and Toronto A26/61 strains is 88.1% , 88.1% and 99.3%, and amino acid identity is 93.6%, 93.6% and 98.6%.The recombinant Loop protein was expressed in E.coli and was approximately 36kDa in size,and then was purified. Then BALB/c mice were injected subcutaneously in the back and armpit with the recombinant Loop protein.The anti-ICHV antibody titers of immunized serum was tested by indirect ELISA and the titers were up to 1320.Western blot demonstrated that immunized sera could specifically combine with ICHV. The research laid a foundation for creating new genetic engineering products of infectious canine hepatitis virus.