Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland; Laboratory of Stem Cell Biology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland; Doctoral School of Exact and Natural Sciences, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland.
Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland.
Cell Rep. 2024 Nov 26;43(11):114779. doi: 10.1016/j.celrep.2024.114779. Epub 2024 Oct 26.
Bone marrow endothelial cells (BM-ECs) are the essential components of the BM niche and support the function of hematopoietic stem cells (HSCs). However, conditioning for HSC transplantation causes damage to the recipients' BM-ECs and may lead to transplantation-related morbidity. Here, we investigated the cellular and clonal mechanisms of BM-EC regeneration after irradiative conditioning. Using single-cell RNA sequencing, imaging, and flow cytometry, we revealed how the heterogeneous pool of BM-ECs changes during regeneration from irradiation stress. Next, we developed a single-cell in vitro clonogenic assay and demonstrated that all EC fractions hold a high potential to reenter the cell cycle and form vessel-like structures. Finally, we used Rainbow mice and a machine-learning-based model to show that the regeneration of BM-ECs after irradiation is mostly polyclonal and driven by the broad fraction of BM-ECs; however, the cell output among clones varies at later stages of regeneration.
骨髓内皮细胞（BM-ECs）是骨髓龛的重要组成部分，支持造血干细胞（HSCs）的功能。然而，HSC 移植的预处理会对受者的 BM-ECs 造成损伤，并可能导致与移植相关的发病率。在这里，我们研究了辐照预处理后 BM-EC 再生的细胞和克隆机制。通过单细胞 RNA 测序、成像和流式细胞术，我们揭示了在辐照应激下，异质的 BM-EC 池在再生过程中是如何变化的。接下来，我们开发了一种单细胞体外克隆形成测定法，并证明所有 EC 部分都具有很高的潜力重新进入细胞周期并形成血管样结构。最后，我们使用 Rainbow 小鼠和基于机器学习的模型表明，辐照后 BM-EC 的再生主要是多克隆的，由广泛的 BM-EC 部分驱动；然而，在再生的后期阶段，克隆之间的细胞输出存在差异。
