title: The expression dynamics of IL-17 and Th17 response relative cytokines in the trachea and spleen of chickens after infection with Cryptosporidium baileyi.
abstract: BACKGROUND
  Cryptosporidium baileyi is the dominant Cryptosporidium species in birds causing emerging health problems in the poultry industry, and is also a model to study the biology of Cryptosporidium spp.. IL-17 (also called IL-17A) is a hallmark pro-inflammatory cytokine of Th17 cells that plays an important role in several human autoimmune diseases and microbial infection disease of many animals, and it may play a role in Cryptosporidium infection.
  
  
  METHODS
  The present study examined the mRNA level of IL-17 and Th17 response relative cytokines in the trachea and spleen of C. baileyi-infected chickens at different time points using real-time quantitative PCR (qPCR).
  
  
  RESULTS
  All examined cytokines in the trachea were up-regulated in the infected chickens compared with the uninfected control during C. baileyi infection. Significant increased IL-17 mRNA level in the trachea was observed as early as 12 h post infection (pi), peaking at 24 h pi and 10 d pi, and declining thereafter. The transcription levels of IL-17 and Th17 response relative cytokines in spleen were also significantly increased at different time points during the infection.
  
  
  CONCLUSIONS
  IL-17 was indicated to participate in the induction of inflammation during infection of some intracellular protozoan parasites. The results in the present study suggest that IL-17 may play a role in immunity against Cryptosporidium infection, and provide basic information for determining the role of Th17 cell in Cryptosporidium infection.
authors.affiliation: College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi Province 712100, People's Republic of China. zgh083@nwsuaf.edu.cn.
authors.forename: Guang-Hui
authors.initials: GH
authors.lastname: Zhao
authors.forename: Wen-Yu
authors.initials: WY
authors.lastname: Cheng
authors.forename: Wan
authors.initials: W
authors.lastname: Wang
authors.forename: Yan-Qing
authors.initials: YQ
authors.lastname: Jia
authors.forename: Yan-Qin
authors.initials: YQ
authors.lastname: Fang
authors.forename: Shuai-Zhi
authors.initials: SZ
authors.lastname: Du
authors.forename: San-Ke
authors.initials: SK
authors.lastname: Yu
mesh_terms: D000818:Animals; D002645:Chickens; D003457:Cryptosporidiosis / Q000276:immunology / Q000378:metabolism*; D003458:Cryptosporidium / Q000145:classification*; D005786:Gene Expression Regulation / Q000276:immunology; D020381:Interleukin-17 / Q000235:genetics / Q000378:metabolism*; D008297:Male; D011201:Poultry Diseases / Q000469:parasitology*; D013154:Spleen / Q000378:metabolism; D058504:Th17 Cells / Q000502:physiology*; D014132:Trachea / Q000378:metabolism*
chemical_list: D020381:Interleukin-17