Abdallah Basem M, Al-Shammary Asma, Skagen Peter, Abu Dawud Raed, Adjaye James, Aldahmash Abdullah, Kassem Moustapha
Molecular Endocrinology Laboratory (KMEB), Department of Endocrinology, Odense University Hospital and University of Southern Denmark, Odense, Denmark; Faculty of Science, Helwan University, Cairo, Egypt.
Molecular Endocrinology Laboratory (KMEB), Department of Endocrinology, Odense University Hospital and University of Southern Denmark, Odense, Denmark.
Stem Cell Res. 2015 Nov;15(3):449-458. doi: 10.1016/j.scr.2015.09.005. Epub 2015 Sep 21.
Bone marrow stromal cells (BMSCs, also known as bone marrow-derived mesenchymal stem cells) and their progenitors have been identified based on retrospective functional criteria. CD markers are employed to define cell populations with distinct functional characteristics. However, defining and prospective isolation of BMSCs and committed progenitors are lacking. Here, we compared the transcriptome profile of CD markers expressed at baseline and during the course of osteoblast and adipocyte differentiation of two well-characterized osteogenic-committed murine BMSCs (mBMSC(Bone)) and adipogenic-committed mBMSCs (mBMSC(Adipo)), respectively. Bioinformatic analysis revealed the presence of a core set of canonical mBMSC CD markers with comparable expression levels in mBMSC(Bone) and mBMSC(Adipo) at baseline and during their differentiation. We identified 11 CD markers that are differentially expressed between mBMSC(Adipo) and mBMSC(Bone). Among these, we identified osteoprogenitor-associated CD markers expressed only in mBMSC(Bone): CD34, CD54, CD73, CD132, CD200, CD227 and adipoprogenitor-associated CD markers expressed only in mBMSC(Adipo): CD53, CD80, CD134, CD141 and CD212. FACS analysis confirmed these results. We selected CD34 for further analysis. CD34 was expressed at baseline of mouse stromal cell line ST2, primary mBMSCs, mBMSC(Bone) and its expression decreased during osteoblast differentiation. FACS-sorted CD34(+) primary mBMSCs exhibited higher expression of 70% osteoblast-associated genes, and formed significantly higher heterotopic bone in vivo when implanted subcutaneously in immune-deficient mice compared with CD34(-) primary mBMSCs. Our results demonstrate that a set of CD markers can distinguish osteoprogenitor versus adipoprogenitor populations of mBMSCs. CD34 is suitable for prospective isolation of mouse bone marrow osteoprogenitors.
骨髓基质细胞（BMSCs，也称为骨髓来源的间充质干细胞）及其祖细胞已根据回顾性功能标准得以鉴定。CD标志物用于定义具有不同功能特征的细胞群体。然而，BMSCs及其定向祖细胞的明确界定和前瞻性分离方法尚不存在。在此，我们比较了两种特征明确的成骨定向小鼠BMSCs（mBMSC(Bone)）和成脂定向mBMSCs（mBMSC(Adipo)）在成骨细胞和脂肪细胞分化基线期及分化过程中所表达的CD标志物的转录组图谱。生物信息学分析显示，在基线期及分化过程中，mBMSC(Bone)和mBMSC(Adipo)存在一组具有相当表达水平的典型mBMSC CD标志物核心集。我们鉴定出11种在mBMSC(Adipo)和mBMSC(Bone)之间差异表达的CD标志物。其中，我们鉴定出仅在mBMSC(Bone)中表达的与骨祖细胞相关的CD标志物：CD34、CD54、CD73、CD132、CD200、CD227，以及仅在mBMSC(Adipo)中表达的与脂肪祖细胞相关的CD标志物：CD53、CD80、CD134、CD141和CD212。荧光激活细胞分选（FACS）分析证实了这些结果。我们选择CD34进行进一步分析。CD34在小鼠基质细胞系ST2、原代mBMSCs、mBMSC(Bone)的基线期表达，在成骨细胞分化过程中其表达下降。与CD34(-)原代mBMSCs相比，FACS分选的CD34(+)原代mBMSCs表现出70%的成骨细胞相关基因更高表达，并且在免疫缺陷小鼠皮下植入时在体内形成的异位骨明显更多。我们的结果表明，一组CD标志物可以区分mBMSCs的骨祖细胞与脂肪祖细胞群体。CD34适用于小鼠骨髓骨祖细胞的前瞻性分离。
