Choi Min-Jeong, You Tae Min, Jang Young-Joo
Department of Nanobiomedical Science and BK21 FOUR NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan 31116, Republic of Korea.
Department of Advanced General Dentistry, School of Dentistry, Dankook University, Cheonan 31116, Republic of Korea.
Stem Cells Int. 2023 Jun 23;2023:5924286. doi: 10.1155/2023/5924286. eCollection 2023.
Human periodontal ligament stem cells (hPDLSCs) contain multipotent postnatal stem cells that differentiate into PDL progenitors, osteoblasts, and cementoblasts. Previously, we obtained cementoblast-like cells from hPDLSCs using bone morphogenetic protein 7 (BMP7) treatment. Differentiation into appropriate progenitor cells requires interactions and changes between stem or progenitor cells and their so-called environment niches, and cell surface markers play an important role. However, cementoblast-specific cell surface markers have not yet been fully studied. Through decoy immunization with intact cementoblasts, we developed a series of monoclonal antibodies against cementoblast-specific membrane/extracellular matrix (ECM) molecules. One of these antibodies, the anti-CM3 antibody, recognized an approximate 30 kDa protein in a mouse cementoblast cell line, and the CM3 antigenic molecule accumulated in the cementum region of human tooth roots. Using mass spectrometric analysis, we found that the antigenic molecules recognized by the anti-CM3 antibody were galectin-3. As cementoblastic differentiation progressed, the expression of galectin-3 increased, and it localized at the cell surface. Inhibition of galectin-3 via siRNA and a specific inhibitor showed the complete blockage of cementoblastic differentiation and mineralization. In contrast, ectopic expression of galectin-3 induced cementoblastic differentiation. Galectin-3 interacted with laminin 2 and BMP7, and these interactions were diminished by galectin-3 inhibitors. These results suggested that galectin-3 participates in binding to the ECM component and trapping BMP7 to induce, in a sustained fashion, the upregulation of cementoblastic differentiation. Finally, galectin-3 could be a potential cementoblast-specific cell surface marker, with functional importance in cell-to-ECM interactions.
人牙周膜干细胞（hPDLSCs）包含多能性的出生后干细胞，这些干细胞可分化为牙周膜祖细胞、成骨细胞和牙骨质细胞。此前，我们通过骨形态发生蛋白7（BMP7）处理从hPDLSCs中获得了牙骨质样细胞。向合适的祖细胞分化需要干细胞或祖细胞与其所谓的微环境之间的相互作用和变化，而细胞表面标志物起着重要作用。然而，牙骨质特异性细胞表面标志物尚未得到充分研究。通过用完整的牙骨质细胞进行诱饵免疫，我们开发了一系列针对牙骨质特异性膜/细胞外基质（ECM）分子的单克隆抗体。其中一种抗体，即抗CM3抗体，在小鼠牙骨质细胞系中识别出一种约30 kDa的蛋白质，并且CM3抗原分子在人牙根的牙骨质区域积累。通过质谱分析，我们发现抗CM3抗体识别的抗原分子是半乳糖凝集素-3。随着牙骨质细胞分化的进行，半乳糖凝集素-3的表达增加，并且它定位于细胞表面。通过小干扰RNA（siRNA）和特异性抑制剂抑制半乳糖凝集素-3显示牙骨质细胞分化和矿化完全受阻。相反，半乳糖凝集素-3的异位表达诱导牙骨质细胞分化。半乳糖凝集素-3与层粘连蛋白2和BMP7相互作用，并且这些相互作用被半乳糖凝集素-3抑制剂减弱。这些结果表明，半乳糖凝集素-3参与与ECM成分的结合并捕获BMP7，以持续方式诱导牙骨质细胞分化的上调。最后，半乳糖凝集素-3可能是一种潜在的牙骨质特异性细胞表面标志物，在细胞与ECM相互作用中具有重要功能。
