METHODS: We used iPSC-derived neurons and astrocytes of patients with autism vs. controls (5/group) to examine whether they replicate the postmortem brain expression/epigenetic alterations of autism. Additionally, DNA methylation of 10 postmortem brain samples (5/group) was analyzed for genes affected in PSC-derived cells.
RESULTS: We found hyperexpression of TGFB1, TGFB2, IL6 and IFI16 and decreased expression of HAP1, SIRT1, NURR1, RELN, GPX1, EN2, SLC1A2 and SLC1A3 in the astrocytes of patients with autism, along with DNA hypomethylation of TGFB2, IL6, TNFA and EN2 gene promoters and a decrease in HAP1 promoter 5-hydroxymethylation in the astrocytes of patients with autism. In neurons, HAP1 and IL6 expression trended alike. While HAP1 promoter was hypermethylated in neurons, IFI16 and SLC1A3 promoters were hypomethylated and TGFB2 exhibited increased promoter 5-hydroxymethlation. We also found a reduction in neuronal arborization, spine size, growth rate, and migration, but increased astrocyte size and a reduced growth rate in autism. In postmortem brain samples, we found DNA hypomethylation of TGFB2 and IFI16 promoter regions, but DNA hypermethylation of HAP1 and SLC1A2 promoters in autism.
CONCLUSIONS: Autism-associated expression/epigenetic alterations in iPSC-derived cells replicated those reported in the literature, making them appropriate surrogates to study disease pathogenesis or patient-specific therapeutics.
方法:我们使用了自闭症患者的iPSC来源的神经元和星形胶质细胞对照组(5/组),以检查他们是否复制了自闭症的死后脑表达/表观遗传学改变。此外,分析10个死后脑样品(5个/组)的DNA甲基化的PSC衍生细胞中受影响的基因。
结果:我们发现TGFB1,TGFB2,IL6和IFI16的过度表达和HAP1,SIRT1,NURR1,RELN,孤独症患者星形胶质细胞中的GPX1,EN2,SLC1A2和SLC1A3,随着TGFB2,IL6,TNFA和EN2基因启动子的DNA低甲基化以及自闭症患者星形胶质细胞中HAP1启动子5-羟甲基化的减少。在神经元中,HAP1和IL6表达趋势相似。虽然HAP1启动子在神经元中高度甲基化,IFI16和SLC1A3启动子被低甲基化,并且TGFB2表现出增加的启动子5-羟基甲基化。我们还发现神经元乔化减少,脊柱尺寸,增长率,和移民,但是自闭症患者的星形胶质细胞大小增加,生长速度降低。在死后的大脑样本中,我们发现TGFB2和IFI16启动子区的DNA低甲基化,但自闭症中HAP1和SLC1A2启动子的DNA甲基化。
结论:iPSC来源的细胞中自闭症相关的表达/表观遗传学改变复制了文献中报道的那些,使它们成为研究疾病发病机理或患者特异性疗法的适当替代品。