Abstract:
Adult stem cells (ASCs) can be cultured with difficulty from most tissues, often requiring chemical or transgenic modification to achieve adequate quantities. We show here that mouse primary fibroblasts, grown in suspension, change from the elongated and flattened morphology observed under standard adherent culture conditions of generating rounded cells with large nuclei and scant cytoplasm and expressing the mesenchymal stem cell (MSC) marker (Sca1; Ly6A) within 24 h. Based on this initial observation, we describe here a suspension culture method that, irrespective of the lineage used, mouse fibroblast or primary human somatic cells (fibroblasts, hepatocytes and keratinocytes), is capable of generating a high yield of cells in spheroid form which display the expression of ASC surface markers, circumventing the anoikis which often occurs at this stage. Moreover, mouse fibroblast-derived spheroids can be differentiated into adipogenic and osteogenic lineages. An analysis of single-cell RNA sequence data in mouse fibroblasts identified eight distinct cell clusters with one in particular comprising approximately 10% of the cells showing high levels of proliferative capacity expressing high levels of genes related to MSCs and self-renewal as well as the extracellular matrix (ECM). We believe the rapid, high-yield generation of proliferative, multi-potent ASC-like cells via the process we term suspension-induced stem cell transition (SIST) could have significant implications for regenerative medicine.
摘要:
成体干细胞(ASCs)可以从大多数组织中很难培养,通常需要化学或转基因修饰才能达到足够的数量。我们在这里展示了小鼠原代成纤维细胞,悬浮生长,在标准贴壁培养条件下观察到的细长和扁平形态的变化,产生具有大核和稀疏细胞质的圆形细胞,并在24小时内表达间充质干细胞(MSC)标记(Sca1;Ly6A)。我们在这里描述一种悬浮培养方法,不管使用的血统,小鼠成纤维细胞或原代人体细胞(成纤维细胞,肝细胞和角质形成细胞),能够以显示ASC表面标志物表达的球体形式产生高产量的细胞,规避经常发生在这个阶段的失巢。此外,小鼠成纤维细胞来源的球体可以分化为成脂和成骨谱系。对小鼠成纤维细胞中的单细胞RNA序列数据的分析鉴定了八个不同的细胞簇,其中一个特别地包含约10%的细胞,显示出高水平的增殖能力,其表达与MSC和自我更新以及细胞外基质(ECM)相关的高水平的基因。我们相信快速,增殖的高产一代,多能ASC样细胞通过我们称之为悬浮诱导干细胞转化(SIST)的过程可能对再生医学具有重要意义。