New recognition of Leishmania major by infected macrophages

点击翻译按钮获取中文摘要

(A)When L.major infected to IRF-4 deficient macrophages in vivo, footpad thickness increased at the early stage (2-5 weeks after infection)compared to wild type.(B)The rate of the L.major infection was same between IRF-4 deficient macrophages and wild-type cells. However, the proportion of the infected macrophages remarkably decreased compared to wild type when L.major infected to IRF-4 deficient macrophages for 48 hrs in vitro, suggested that IRF-4 negatively regulated exclusion of L.major from the infected macrophages. TNF-α and NO from IRF-4 deficient, L.major-infected macrophages produced much higher than wild-type. Interestingly, IL-12 from IRF-4 deficient, and L.major infected macrophages produced much lower than wild-type. We expected that signaling to recognize L.major was different from TLR signaling because we have already reported that both IL-12 and TNF-α production through TLR remarkably enhanced in IRF-4 deficient macrophages. Alternation of cytokine production in IRF-4 KO macrophages to infect with L.major regulated at the transcriptional level. Various kind of denatured L.major antigens were made to identify major L.major molecule. Heat denatured or Proteinase K treated L.major antigen did not affect cytokine production pattern of TNF-α or IL-12 in IRF-4 KO macrophages. L.major molecule contained in insoluble fraction and was Proteinase K resistant molecule. It suggested that major antigen was not protein. And it was impossible to use ion exchange chromatography such as Bio-Cad.(C)To separate L.major antigen, gel filtration method have been performed because it was able to separate each molecules by molecular weight.