Establishment of in-house cDNA microarray for analysis of pathogenicity of Toxoplasma gondii infection and developing methods of diagnosis and therapy for toxoplasmosis

点击翻译按钮获取中文摘要

By using our own made cDNA microarray system composed with around 15,000 clones established by using mRNA from normal mice, Toxoplasma gondii-infection-induced genes were analyzed Five gene groups, beta2-microblobulin, DMR, spot 14, teststeron, and an unknown (tentatively named as T.g.Res.X ) were picked up. T.g.Res.X was shown to express in a resistant strain to T.gondii infection when the mRNA expression was examined by comparing between a wild type resistant strain(BALB/c) and a wild type susceptible strain( C57BL/6), and also comparing between wild type and IFN-_γ KO BALB/c mice.Effects of interferon-gamma (IFN-_γ) on stage conversion between bradyzoites and tachyzoites of Toxoplasma gondii were investigated by measuring a virulent gene of T.gondii, heat shock protein 70 (T.g.HSP70), a bradyzoite-specifc gene, T.g.HSP30/bag1, and a tachyzoite-specific gene, SAG1 mRNAs with cDNA microarray method in wild type and IFN-γ knockout (KO) mice. In wild type mice, T.g.HSP30/bag1 mRNA expression continued for 3 days post infection(PI), while SAG1 mRNA expressed for 9 days PI. In IKO mice, T.g.HSP30/bag1 mRNA expression decreased drastically 24 hr post PI, and SAG1 mRNA began to express interchangeably. Then T.g.HSP70 mRNA expressed rapidly 7-8 days PI, and the mice died just after T.g.HSP70 mRNA expression. Thus, IFN-γ downregulates SAG1 and T.g.HSP70 mRNA expression.