Mammalian Cell-Line-Expressed CD2v Protein of African Swine Fever Virus Provides Partial Protection against the HLJ/18 Strain in the Early Infection Stage
Rong-Hong Hua,
Jing Liu,
Shu-Jian Zhang,
Ren-Qiang Liu,
Xian-Feng Zhang,
Xi-Jun He,
Dong-Ming Zhao,
Zhi-Gao Bu
Affiliations
Rong-Hong Hua
State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
Jing Liu
State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
Shu-Jian Zhang
State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
Ren-Qiang Liu
State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
Xian-Feng Zhang
State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
Xi-Jun He
State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
Dong-Ming Zhao
State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
Zhi-Gao Bu
State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
A cell line expressing the CD2v protein of ASFV was generated. The efficient expression of CD2v protein was determined by immunofluorescence and Western blotting. The CD2v protein was Ni-affinity purified from the supernatant of cell cultures. The CD2v-expressing cells showed properties of hemadsorption, and the secreted CD2v protein exhibited hemagglutinating activity. The antigenicity and immunoprotection ability of CD2v were evaluated by immunizing pigs alone, combined with a cell-line-expressed p30 protein or triple combined with p30 and K205R protein. Immunized pigs were challenged with the highly virulent ASFV strain HLJ/18. Virus challenge results showed that CD2v immunization alone could provide partial protection at the early infection stage. Protein p30 did not show synergistic protection effects in immunization combined with CD2v. Interestingly, immunization with the triple combination of CD2V, p30 and K205R reversed the protection effect. The viremia onset time was delayed, and one pig out of three recovered after the challenge. The pig recovered from ASFV clinical symptoms, the rectal temperature returned to normal levels and the viremia was cleared. The mechanism of this protection effect warrants further investigation.
