Tissue Engineering Laboratory & Berlin-Brandenburg Center for Regenerative Therapies, Dept. of Rheumatology and Clinical Immunology, Charité-University Medicine Berlin, Charitéplatz 1, 10117 Berlin, Germany.
Matrix Biol. 2013 Oct-Nov;32(7-8):452-65. doi: 10.1016/j.matbio.2013.07.001. Epub 2013 Jul 12.
Extracellular matrix (ECM) is the non-cellular component of tissues, which not only provides biological shelter but also takes part in the cellular decisions for diverse functions. Every tissue has an ECM with unique composition and topology that governs the process of determination, differentiation, proliferation, migration and regeneration of cells. Little is known about the structural organization of matrix especially of MSC-derived adipogenic ECM. Here, we particularly focus on the composition and architecture of the fat ECM to understand the cellular behavior on functional bases. Thus, mesenchymal stem cells (MSC) were adipogenically differentiated, then, were transferred to adipogenic propagation medium, whereas they started the release of lipid droplets leaving bare network of ECM. Microarray analysis was performed, to indentify the molecular machinery of matrix. Adipogenesis was verified by Oil Red O staining of lipid droplets and by qPCR of adipogenic marker genes PPARG and FABP4. Antibody staining demonstrated the presence of collagen type I, II and IV filaments, while alkaline phosphatase activity verified the ossified nature of these filaments. In the adipogenic matrix, the hexagonal structures were abundant followed by octagonal structures, whereas they interwoven in a crisscross manner. Regarding molecular machinery of adipogenic ECM, the bioinformatics analysis revealed the upregulated expression of COL4A1, ITGA7, ITGA7, SDC2, ICAM3, ADAMTS9, TIMP4, GPC1, GPC4 and downregulated expression of COL14A1, ADAMTS5, TIMP2, TIMP3, BGN, LAMA3, ITGA2, ITGA4, ITGB1, ITGB8, CLDN11. Moreover, genes associated with integrins, glycoproteins, laminins, fibronectins, cadherins, selectins and linked signaling pathways were found. Knowledge of the interactive-language between cells and matrix could be beneficial for the artificial designing of biomaterials and bioscaffolds.
细胞外基质（ECM）是组织的非细胞成分，不仅提供生物庇护所，还参与细胞的各种功能决策。每种组织都有独特组成和拓扑结构的 ECM，它控制着细胞的决定、分化、增殖、迁移和再生过程。关于基质的结构组织，特别是 MSC 衍生的脂肪生成 ECM，人们知之甚少。在这里，我们特别关注脂肪 ECM 的组成和结构，以在功能基础上了解细胞行为。因此，间充质干细胞（MSC）被脂肪生成分化，然后转移到脂肪生成增殖培养基中，此时它们开始释放脂质滴，留下裸露的 ECM 网络。进行了微阵列分析，以确定基质的分子机制。通过脂质滴的油红 O 染色和脂肪生成标记基因 PPARG 和 FABP4 的 qPCR 验证脂肪生成。抗体染色表明存在胶原 I、II 和 IV 纤维，而碱性磷酸酶活性验证了这些纤维的骨化性质。在脂肪生成的基质中，六方结构丰富，其次是八角结构，它们以交错的方式交织在一起。关于脂肪生成 ECM 的分子机制，生物信息学分析显示 COL4A1、ITGA7、ITGA7、SDC2、ICAM3、ADAMTS9、TIMP4、GPC1、GPC4 的表达上调，COL14A1、ADAMTS5、TIMP2、TIMP3、BGN、LAMA3、ITGA2、ITGA4、ITGB1、ITGB8、CLDN11 的表达下调。此外，还发现了与整合素、糖蛋白、层粘连蛋白、纤连蛋白、钙粘蛋白、选择素和相关信号通路相关的基因。了解细胞与基质之间的交互语言可能有助于人工设计生物材料和生物支架。
