Lyu Feng-Juan
Joint Center for Regenerative Medicine Research of South China University of Technology-the University of Western Australia, School of Medicine, South China University of Technology, Guangzhou 510006, China.
Bioengineering (Basel). 2022 Apr 1;9(4):148. doi: 10.3390/bioengineering9040148.
Intervertebral disc (IVD) degeneration occurs with natural ageing and is linked to low back pain, a common disease. As an avascular tissue, the microenvironment inside the IVD is harsh. During degeneration, the condition becomes even more compromised, presenting a significant challenge to the survival and function of the resident cells, as well as to any regeneration attempts using cell implantation. Mesenchymal stem cells (MSCs) have been proposed as a candidate stem cell tool for IVD regeneration. Recently, endogenous IVD progenitor cells have been identified inside the IVD, highlighting their potential for self-repair. IVD progenitor cells have properties similar to MSCs, with minor differences in potency and surface marker expression. Currently, it is unclear how IVD progenitor cells react to microenvironmental factors and in what ways they possibly behave differently to MSCs. Here, we first summarized the microenvironmental factors presented in the IVD and their changes during degeneration. Then, we analyzed the available studies on the responses of IVD progenitor cells and MSCs to these factors, and made comparisons between these two types of cells, when possible, in an attempt to achieve a clear understanding of the characteristics of IVD progenitor cells when compared to MSCs; as well as, to provide possible clues to cell fate after implantation, which may facilitate future manipulation and design of IVD regeneration studies.
椎间盘（IVD）退变随着自然衰老而发生，并且与腰痛这一常见疾病相关。作为一种无血管组织，IVD内部的微环境恶劣。在退变过程中，这种状况变得更加糟糕，对驻留细胞的存活和功能以及任何使用细胞植入的再生尝试都构成了重大挑战。间充质干细胞（MSCs）已被提议作为IVD再生的候选干细胞工具。最近，IVD内已鉴定出内源性IVD祖细胞，突出了它们的自我修复潜力。IVD祖细胞具有与MSCs相似的特性，在分化潜能和表面标志物表达方面存在细微差异。目前，尚不清楚IVD祖细胞如何对微环境因素作出反应，以及它们与MSCs可能在哪些方面表现不同。在此，我们首先总结了IVD中存在的微环境因素及其在退变过程中的变化。然后，我们分析了关于IVD祖细胞和MSCs对这些因素反应的现有研究，并在可能的情况下对这两种类型的细胞进行比较，试图清楚地了解与MSCs相比IVD祖细胞的特征；以及为植入后的细胞命运提供可能的线索，这可能有助于未来IVD再生研究的操作和设计。
