title: [Infiltration of DCs and CD4+ T cells in muscle after DNA immunization].
abstract: OBJECTIVE
  In order to get a better understanding of the mechanism of DNA initiating specific cytotoxicity T lymphocyte (CTL) immune response, we observed the local infiltration in injection site at different time after DNA immunization and further studied the characters of infiltration cells.
  
  
  METHODS
  The local infiltration in injection sites was observed by HE staining at 6 h, 12 h and 1-6 days after DNA immunization. Infiltration cells were further studied with the mice dendritic cells marker CD205, T lymphocyte marker CD4 and CD8 by immunohistological methods.
  
  
  RESULTS
  phAFP injection into mouse muscle led to a local infiltration. Infiltrates reached peak at 3-6 days after injection and appeared in several discrete clusters within the muscles. The predominant cell types found in infiltrates were macrophage-like cells and lymphocytes. Immunohistological staining revealed CD205+ and CD4+ cells. CD4+ cells could be detected in any of the injected muscles. CD205+ cells were only seen at 24 h to day 3, appearing later and disappearing earlier than CD4+ cells. However, CD8+ immunostaining positivity could not be found.
  
  
  CONCLUSIONS
  Our findings indicate that the character of local infiltration after DNA immunization is different from the inflammation of injection. The recruitment of CD205+ to the injection site suggests that DCs and Th cells play an important role in DNA immunization.
authors.affiliation: Department of Immunology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu 610041, China.
authors.forename: Xiao-ling
authors.initials: XL
authors.lastname: Deng
authors.forename: Xia
authors.initials: X
authors.lastname: Wang
authors.forename: Da-peng
authors.initials: DP
authors.lastname: Wei
authors.forename: Ping
authors.initials: P
authors.lastname: Zhang
authors.forename: Mei-ying
authors.initials: MY
authors.lastname: Cai
authors.forename: Jian-hong
authors.initials: JH
authors.lastname: Bi
authors.forename: Li-luan
authors.initials: LL
authors.lastname: Hu
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D003713:Dendritic Cells / Q000276:immunology*; D007273:Injections, Intramuscular; D051379:Mice; D008807:Mice, Inbred BALB C; D018482:Muscle, Skeletal / Q000276:immunology; D014611:Vaccination; D019444:Vaccines, DNA / Q000276:immunology*
chemical_list: D019444:Vaccines, DNA