Tissue memory of DNA methylation in iPSC of diverse somatic cells

Several studies have discussed the possibility that donor cell type may influence the epigenetics and differentiation potential of iPSCs, but it remains unclear whether iPS cells derived from different tissue sources reserve their epigenetic memory. Here, we clarify that iPSCs obtained from different tissues exhibit specific epigenetic patterns. We determined the DNA methylation profiles of 12 human cell lines, including 3 adult fibroblast cell-derived iPSC lines, 2 peripheral blood-derived mononuclear cell(PBMC)-derived iPSC lines, 2 amniotic cell-derived iPSC lines and the 5 corresponding parent cell lines. We found that the catalog of tissue-specific DNA methylation was preserved in the iPSC line as epigenetic memory during reprogramming. 12 human cell lines, including 2 adult fibroblast cell-derived iPSC lines, 3 peripheral blood-derived mononuclear cell(PBMC)-derived iPSC lines, 2 amniotic cell-derived iPSC lines and the 5 corresponding parental cell lines

已有多项研究探讨了供体细胞类型可能影响诱导多能干细胞（induced pluripotent stem cells, iPSCs）的表观遗传学特性与分化潜能的可能性，但目前仍不明确不同组织来源的诱导多能干细胞是否会保留其表观遗传记忆。本研究明确了不同组织来源的诱导多能干细胞会呈现出特异性的表观遗传模式。本研究测定了12株人细胞系的DNA甲基化谱，其中包括3株成人成纤维细胞来源的诱导多能干细胞系、2株外周血单个核细胞（peripheral blood mononuclear cell, PBMC）来源的诱导多能干细胞系、2株羊膜细胞来源的诱导多能干细胞系，以及对应的5株亲本细胞系。研究发现，在重编程过程中，组织特异性DNA甲基化特征作为表观遗传记忆被保留在诱导多能干细胞系中。本次研究涉及的12株人细胞系，还包含2株成人成纤维细胞来源的诱导多能干细胞系、3株外周血单个核细胞（PBMC）来源的诱导多能干细胞系、2株羊膜细胞来源的诱导多能干细胞系，以及对应的5株亲本细胞系。