Mesenchymal stem cells (MSCs) are multipotent progenitor cells in adult tissues. The aim of this study is to isolate and identify synovial fluid-derived mesenchymal stromal cells (SF-MSCs) from the popliteal cyst fluid of pediatric patients. SF-MSCs were collected from the popliteal cyst fluid of pediatric patients during cystectomy surgery. After cyst fluid extraction and adherent culturing, in vitro morphology, growth curve, and cell cycle were observed. The expression of stem cell surface markers was analyzed by flow cytometry, and expression of cell marker protein was detected by immunofluorescence. SF-MSCs were cultured in osteogenic, adipogenic, and chondrogenic differentiation medium. The differentiation potential of SF-MSCs was analyzed by alkaline phosphatase (Alizarin Red), Oil Red O, and Alcian blue. Antibody detection of human angiogenesis-related proteins was performed compared with bone marrow mesenchymal stem cells (BM-MSCs). The results show that SF-MSCs from the popliteal cyst fluid of pediatric patients showed a shuttle appearance and logarithmic growth. Flow cytometry analysis revealed that SF-MSCs were negative for hematopoietic lineage markers (CD34, CD45) and positive for MSC markers (CD44, CD73, CD90, and CD105). Interstitial cell marker (vimentin) and myofibroblast-like cell marker alpha-smooth muscle actin (α-SMA) were positive. These cells could differentiate into osteogenic, adipogenic, and chondrogenic lineages, respectively. Several types of human angiogenesis-related proteins were detected in the cell secretory fluid. These results show that we successfully obtained SF-MSCs from the popliteal cyst fluid of pediatric patients, which have the potential to be a valuable source of MSCs.

中文翻译：

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人滑膜液衍生的Pop细胞间充质基质细胞的分离与鉴定

间充质干细胞（MSCs）是成人组织中的多能祖细胞。这项研究的目的是从儿科患者的lite囊液中分离和鉴定滑膜源性间充质基质细胞（SF-MSC）。SF-MSCs在膀胱切除术期间从儿科患者的lite囊液中收集。提取囊肿液并贴壁培养后，观察其体外形态，生长曲线和细胞周期。通过流式细胞术分析干细胞表面标志物的表达，并通过免疫荧光检测细胞标志物蛋白的表达。SF-MSC在成骨，成脂和成软骨分化培养基中培养。SF-MSCs的分化潜能通过碱性磷酸酶（茜素红），油红O和阿尔辛蓝进行了分析。与骨髓间充质干细胞（BM-MSC）相比，进行了人类血管生成相关蛋白的抗体检测。结果表明，儿科患者the囊液中的SF-MSCs呈穿梭状，对数增长。流式细胞仪分析显示，SF-MSCs造血谱系标记（CD34，CD45）阴性，而MSC标记（CD44，CD73，CD90和CD105）阳性。间质细胞标志物（波形蛋白）和成肌纤维样细胞标志物α-平滑肌肌动蛋白（流式细胞仪分析显示，SF-MSCs造血谱系标记（CD34，CD45）阴性，而MSC标记（CD44，CD73，CD90和CD105）阳性。间质细胞标志物（波形蛋白）和成肌纤维样细胞标志物α-平滑肌肌动蛋白（流式细胞仪分析显示，SF-MSCs造血谱系标记（CD34，CD45）阴性，而MSC标记（CD44，CD73，CD90和CD105）阳性。间质细胞标志物（波形蛋白）和成肌纤维样细胞标志物α-平滑肌肌动蛋白（α- SMA）为阳性。这些细胞可以分别分化为成骨，成脂和成软骨谱系。在细胞分泌液中检测到几种类型的人类血管生成相关蛋白。这些结果表明，我们成功地从儿科患者的lite囊液中获得了SF-MSC，它们有可能成为MSC的宝贵来源。