Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA 30332.
Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA 30322.
Proc Natl Acad Sci U S A. 2018 Apr 24;115(17):4357-4362. doi: 10.1073/pnas.1714820115. Epub 2018 Apr 9.
The ability to analyze and isolate cells based on the expression of specific surface markers has increased our understanding of cell biology and produced numerous applications for biomedicine. However, established cell-sorting platforms rely on labels that are limited in number due to biophysical constraints, such as overlapping emission spectra of fluorophores in FACS. Here, we establish a framework built on a system of orthogonal and extensible DNA gates for multiplexed cell sorting. These DNA gates label target cell populations by antibodies to allow magnetic bead isolation en masse and then selectively unlock by strand displacement to sort cells. We show that DNA gated sorting (DGS) is triggered to completion within minutes on the surface of cells and achieves target cell purity, viability, and yield equivalent to that of commercial magnetic sorting kits. We demonstrate multiplexed sorting of three distinct immune cell populations (CD8, CD4, and CD19) from mouse splenocytes to high purity and show that recovered CD8 T cells retain proliferative potential and target cell-killing activity. To broaden the utility of this platform, we implement a double positive sorting scheme using DNA gates on peptide-MHC tetramers to isolate antigen-specific CD8 T cells from mice infected with lymphocytic choriomeningitis virus (LCMV). DGS can potentially be expanded with fewer biophysical constraints to large families of DNA gates for applications that require analysis of complex cell populations, such as host immune responses to disease.
基于特定表面标志物的表达来分析和分离细胞的能力提高了我们对细胞生物学的理解,并为生物医学产生了许多应用。然而,现有的细胞分选平台依赖于标签,由于生物物理限制,标签的数量有限,例如在流式细胞术中荧光染料的发射光谱重叠。在这里,我们建立了一个基于正交和可扩展 DNA 门的框架,用于多重细胞分选。这些 DNA 门通过抗体标记靶细胞群体,允许大规模进行磁珠分离,然后通过链置换选择性解锁以分选细胞。我们表明,DNA 门控分选(DGS)在细胞表面几分钟内即可触发完成,并且达到与商业磁性分选试剂盒相当的目标细胞纯度、活力和产量。我们证明了从小鼠脾细胞中对三种不同免疫细胞群体(CD8、CD4 和 CD19)进行多重分选,达到高纯度,并表明回收的 CD8 T 细胞保持增殖潜力和靶细胞杀伤活性。为了扩大这个平台的应用范围,我们在肽-MHC 四聚体上的 DNA 门上实施了双阳性分选方案,以从感染淋巴细胞性脉络丛脑膜炎病毒 (LCMV) 的小鼠中分离抗原特异性 CD8 T 细胞。DGS 可以在较少的生物物理限制下扩展到更大的 DNA 门家族,用于需要分析复杂细胞群体的应用,例如宿主对疾病的免疫反应。