title: Dynamic distribution and tissue tropism of classical swine fever virus in experimentally infected pigs.
abstract: BACKGROUND
  Classical swine fever (CSF), caused by the Classical swine fever virus (CSFV), is an Office International des Epizooties (OIE) notifiable disease. However, we are far from fully understand the distribution, tissue tropism, pathogenesis, replication and excretion of CSFV in pigs. In this report, we investigated the dynamic distribution and tissue tropism of the virus in internal organs of the experimentally infected pigs using real-time RT-PCR and immunohistochemistry (IHC).
  
  
  RESULTS
  A relative quantification real-time PCR was established and used to detect the virus load in internal organs of the experimentally infected pigs. The study revealed that the virus was detected in all 21 of the internal organs and blood collected from pigs at day 1 to day 8 post infections, and had an increasing virus load from day 1 to day 8 post infections. However, there was irregular distribution virus load in most internal organs over the first 2 days post infection. Blood, lymphoid tissue, pancreas and ileum usually contain the highest viral loads, while heart, duodenum and brain show relatively low viral loads.
  
  
  CONCLUSIONS
  All the data suggest that CSFV had an increasing virus load from day 1 to day 8 post infections in experimentally infected pigs detected by real-time RT-PCR, which was in consistent with the result of the IHC staining. The data also show that CSFV was likely to reproduce in blood, lymphoid tissue, pancreas and the ileum, while unlikely to replicate in the heart, duodenum and brain. The results provide a foundation for further clarification of the pathogenic mechanism of CSFV in internal organs, and indicate that blood, lymphoid tissue, pancreas and ileum may be preferred sites of acute infection.
authors.affiliation: China Institute of Veterinary Drug Control, National Classical Swine Fever Reference Laboratory, Beijing 100081, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.forename: Xue-Zheng
authors.initials: XZ
authors.lastname: Fan
authors.forename: Qin
authors.initials: Q
authors.lastname: Wang
authors.forename: Lu
authors.initials: L
authors.lastname: Xu
authors.forename: Qi-Zu
authors.initials: QZ
authors.lastname: Zhao
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Yuan-Cheng
authors.initials: YC
authors.lastname: Zhou
authors.forename: Bo
authors.initials: B
authors.lastname: Tang
authors.forename: Lei
authors.initials: L
authors.lastname: Chen
authors.forename: Xing-Qi
authors.initials: XQ
authors.lastname: Zou
authors.forename: Sha
authors.initials: S
authors.lastname: Sha
authors.forename: Yuan-Yuan
authors.initials: YY
authors.lastname: Zhu
mesh_terms: D000825:Animal Structures / Q000821:virology; D000818:Animals; D000956:Antigens, Viral / Q000032:analysis; D006691:Classical Swine Fever / Q000821:virology*; D006692:Classical Swine Fever Virus / Q000472:pathogenicity*; D004195:Disease Models, Animal; D007150:Immunohistochemistry; D008853:Microscopy; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013552:Swine; D056189:Viral Tropism
chemical_list: D000956:Antigens, Viral; D012367:RNA, Viral