Molecular Genetics of Stem Cells Laboratory, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, H3T 1J4 QC, Canada.
Molecular Genetics of Stem Cells Laboratory, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, H3T 1J4 QC, Canada; Division of Hematology, Maisonneuve-Rosemont Hospital, Montréal, H1T 2M4 QC, Canada; Department of Medicine, Faculty of Medicine, Université de Montréal, Montréal, H3T 1J4 QC, Canada.
Cell Rep. 2019 Jul 23;28(4):1063-1073.e5. doi: 10.1016/j.celrep.2019.06.084.
Transplantation of expanded hematopoietic stem cells (HSCs) and gene therapy based on HSC engineering have emerged as promising approaches for the treatment of hematological diseases. Nevertheless, the immunophenotype of cultured HSCs remains poorly defined. Here, we identify Integrin-α3 (ITGA3) as a marker of cultured human HSCs. Exploiting the pyrimidoindole derivative UM171 to expand cord blood (CB) cells, we show that ITGA3 expression is sufficient to separate the primitive EPCRCD90CD133CD34CD45RA HSC population into two functionally distinct fractions presenting mostly short-term (ITGA3) and both short-term and long-term (ITGA3) repopulating potential. ITGA3 cells exhibit robust multilineage differentiation potential, serial reconstitution ability in immunocompromised mice, and an HSC-specific transcriptomic signature. Moreover, ITGA3 expression is functionally required for the long-term engraftment of CB cells. Altogether, our results indicate that ITGA3 is a reliable marker of cultured human long-term repopulating HSCs (LT-HSCs) and represents an important tool to improve the accuracy of prospective HSC identification in culture.
移植扩增的造血干细胞（HSCs）和基于 HSC 工程的基因治疗已成为治疗血液疾病的有前途的方法。然而，培养的 HSCs 的免疫表型仍未得到很好的定义。在这里，我们确定整合素-α3（ITGA3）为培养的人类 HSCs 的标志物。利用嘧啶并吲哚衍生物 UM171 扩增脐带血（CB）细胞，我们表明 ITGA3 表达足以将原始 EPCRCD90CD133CD34CD45RA HSC 群体分为两个功能不同的部分，主要呈现短期（ITGA3）和短期及长期（ITGA3）再生潜能。ITGA3 细胞表现出强大的多谱系分化潜能、在免疫抑制小鼠中的连续重建能力以及 HSC 特异性转录组特征。此外，ITGA3 表达对 CB 细胞的长期植入是功能必需的。总之，我们的结果表明，ITGA3 是培养的人类长期再生 HSC（LT-HSCs）的可靠标志物，是提高培养中 HSC 鉴定准确性的重要工具。
