State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, P.R. China.
Department of Laboratory Medicine, The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, P.R. China.
Prog Mol Biol Transl Sci. 2023;199:271-296. doi: 10.1016/bs.pmbts.2023.02.014. Epub 2023 Mar 16.
It is urgent to prepare and store large numbers of clinical trial grade human pluripotent stem (hPS) cells for off-the-shelf use in stem cell therapies. However, stem cell banks, which store off-the-shelf stem cells, need financial support and large amounts of technicians for daily cell maintenance. Therefore, it is valuable to create "universal" or "hypoimmunogenic" hPS cells with genome editing engineering by knocking in or out immune-related genes. Only a small number of universal or hypoimmunogenic hPS cell lines should be needed to store for off-the-shelf usage and reduce the large amounts of instruments, consumables and technicians. In this article, we consider how to create hypoimmunogenic or universal hPS cells as well as the demerits of the technology. β2-Microglobulin-knockout hPS cells did not harbor human leukocyte antigen (HLA)-expressing class I cells but led to the activation of natural killer cells. To escape the activities of macrophages and natural killer cells, homozygous hPS cells having a single allele of an HLA class I gene, such as HLA-C, were proposed. Major HLA class Ia molecules were knocked out, and CD47, HLA-G and PD-L1 were knocked in hPS cells utilizing CRISPR/Cas9 genome editing. Finally, some researchers are trying to generate universal hPS cells without genome editing. The cells evaded the activation of not only T cells but also macrophages and natural killer cells. These universal hPS cells have high potential for application in cell therapy.
为了在干细胞治疗中实现现成的应用，迫切需要制备和储存大量的临床级别的人多能干细胞（hPS）。然而，储存现成干细胞的干细胞库需要财政支持和大量的技术人员来进行日常的细胞维护。因此，通过基因编辑工程敲入或敲除免疫相关基因来创建具有“通用性”或“低免疫原性”的 hPS 细胞是有价值的。通过敲入或敲除免疫相关基因，只需要少量的通用或低免疫原性 hPS 细胞系即可用于储存和减少大量的仪器、耗材和技术人员。在本文中，我们考虑了如何创建低免疫原性或通用的 hPS 细胞，以及该技术的缺点。β2-微球蛋白敲除 hPS 细胞不表达人类白细胞抗原（HLA）-表达 I 类细胞，但会导致自然杀伤细胞的激活。为了逃避巨噬细胞和自然杀伤细胞的活性，提出了具有 HLA I 类基因单一等位基因（如 HLA-C）的纯合 hPS 细胞。利用 CRISPR/Cas9 基因组编辑敲除主要的 HLA I 类分子，并敲入 hPS 细胞中的 CD47、HLA-G 和 PD-L1。最后，一些研究人员正在尝试生成无需基因组编辑的通用 hPS 细胞。这些细胞不仅逃避了 T 细胞的激活，还逃避了巨噬细胞和自然杀伤细胞的激活。这些通用 hPS 细胞在细胞治疗中有很高的应用潜力。
