Prokaryotic expression of HN gene of bovine parainfluenza virus type 3 and the establishment of indirect ELISA method / 病毒学报

The prokaryotic expression plasmid pQE30-HN of hemagglutinin-neuraminidase (HN) protein gene of bovine parainfluenza virus type 3 (BPIV3) strain HJ-1 was expressed by IPTG induction in E. coli XL1Blue. The recombinant HN protein(rHN) was purified by electroeluting method, and used as coated antigen. An indirect enzyme-linked immunosorbent assay (ELISA) was developed to detect the antibody valence of BPIV3. The best working conditions of ELISA were as follows: the antigen concentration was 6 microg/mL; the serum dilution was 1:50; the blocking reagent was 5% skimmed milk; the blocking time was 60 min at 37 degrees C; the second antibody concentration was 1:10 000; The cut-off value was 0.30. The method revealed a good specificity, no cross-reaction to the positive sera of BCV, IBRV or BRSV was observed. We applied the method to detect 323 serum samples of dairy cow in Heilongjiang Province, the seropositivity rate of BPIV3 was about 58%. The indirect ELISA established provided a technological basis for the development of ELISA kit.

Molecular characteristics and immune evasion strategies of ORFV: a review / 病毒学报

Contagious ecthyma (also known as orf) is an acute skin zoonosis caused by orf virus (ORFV), which affects sheep, goats and humans. As one of the typical species of the Parapoxvirus genus of the Poxviridae family, orf virus has distinctive and unique characteristics of these species. A range of immuno-modulatory/pathogenesis -related genes acquired by virus that function is to limit (at least transiently) the effectiveness of host immunity during its evolution. This review is aimed to describe the latest progress on the molecular characteristics of ORFV, and upon which we analyzed molecular mechanism of the immune escape designed and a set of strategies developed for ORFV to effective against immune clearance of the host. Known as an essential component in evolutionary system, host is regulated by ORFV for using in population evolution. By the ORFV evolutional immune regulation components and its effect approach, we can understand the viral biological characteristics of ORFV, and it is helpful for us to further study the counter-measures of this disease.