title: Porcine Mx1 fused to HIV Tat protein transduction domain (PTD) inhibits classical swine fever virus infection in vitro and in vivo.
abstract: BACKGROUND
  Classical swine fever (CSF) caused by CSF virus (CSFV) is highly contagious andcauses significant economic losses in the pig industry throughout the world. Previously we demonstrated that porcine Mx1 (poMx1), when fused to HIV Tat protein transduction domain (PTD), inhibits CSFV propagation in PK-15 cells, but it is unknown whether PTD-poMx1 exhibits antiviral activity in other porcine lines and it is efficacious for controlling CSFV infection in pigs in China.
  
  
  METHODS
  Two porcine cell lines, ST and 3D4/21, were used to investigate in vitro antiviral activity of PTD-poMx1 against CSFV using confocal microscopy, western blot, flow cytometry, and real-time RT-PCR. Furthermore, in vivo antiviral activity of PTD-poMx1 was assessed by means of rectal temperature, clinical score, pathological lesion, white blood cell count, viral load, etc.
  
  
  RESULTS
  PTD-poMx1 entered both cell lines within 3 h and maintained for 16 h, but did not affect CSFV binding and uptake. Viral titers and qRT-PCR data showed that PTD-poMx1 inhibited CSFV replication in both cell lines, showing significant antiviral activity after infection. Injection of PTD-poMx1 into CSFV-challenged pigs attenuated CSFV symptoms and viremia in dose-dependent manner but did not completely block virus replication within 14 days post challenge, suggesting that PTD-poMx1 confers partial protection against a lethal challenge.
  
  
  CONCLUSIONS
  We demonstrated the anti-CSFV activity of PTD-poMx1 in vitro and in vivo. The results have shown that treatment with PTD-poMx1 alleviated symptoms and viral load in infected pigs. The results support our previous in vitro studies and suggest that PTD-poMx1 could be promising in reducing the clinical signs caused by CSFV.
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China. 718697631@qq.com.
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Zhang
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China. 609109028@qq.com.
authors.forename: Jiao
authors.initials: J
authors.lastname: Jing
authors.affiliation: Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China. 402251492@qq.com.
authors.forename: Wenliang
authors.initials: W
authors.lastname: Li
authors.affiliation: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, 200241, China. 249094364@qq.com.
authors.forename: Ke
authors.initials: K
authors.lastname: Liu
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China. 365703463@qq.com.
authors.forename: Baojun
authors.initials: B
authors.lastname: Shi
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China. 1363623321@qq.com.
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Xu
authors.affiliation: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, 200241, China. zhiyongma@shvri.ac.cn.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Ma
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China. zhoubin@njau.edu.cn.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China. 1750706260@qq.com.
authors.forename: Puyan
authors.initials: P
authors.lastname: Chen
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D006691:Classical Swine Fever / Q000517:prevention & control*; D006692:Classical Swine Fever Virus / Q000235:genetics / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005434:Flow Cytometry / Q000662:veterinary; D066298:In Vitro Techniques; D018613:Microscopy, Confocal / Q000662:veterinary; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D013552:Swine; D014161:Transduction, Genetic / Q000379:methods / Q000662:veterinary; D014614:Vaccines, Synthetic / Q000235:genetics / Q000627:therapeutic use; D014765:Viral Vaccines / Q000235:genetics / Q000627:therapeutic use*; D014766:Viremia / Q000662:veterinary; D054322:tat Gene Products, Human Immunodeficiency Virus / Q000235:genetics*
chemical_list: D014614:Vaccines, Synthetic; D014765:Viral Vaccines; D054322:tat Gene Products, Human Immunodeficiency Virus