Udagawa N, Takahashi N, Akatsu T, Sasaki T, Yamaguchi A, Kodama H, Martin T J, Suda T
Department of Biochemistry, Showa University, School of Dentistry, Tokyo, Japan.
Endocrinology. 1989 Oct;125(4):1805-13. doi: 10.1210/endo-125-4-1805.
After our previous report that osteoclast-like multinucleated cells (MNCs) were formed in response to 1 alpha,25-dihydroxyvitamin D3 [1 alpha,25-(OH)2D3] in cocultures of mouse spleen cells and osteoblast-rich populations freshly isolated from fetal mouse calvariae, we examined whether such primary osteoblast-like cells can be replaced by established cell lines in inducing osteoclast-like cell formation. We first used two clonal cell lines simultaneously established from newborn mouse calvariae. One was the osteoblastic cell line MC3T3-E1, and the other was the preadipose cell line MC3T3-G2/PA6. Tartrate-resistant acid phosphatase (TRACP; a marker enzyme of osteoclasts)-positive mononuclear cells and MNCs were formed in the cocultures of spleen cells and MC3T3-G2/PA6 cells in the presence of 1 alpha,25-(OH)2D3. Dexamethasone greatly potentiated TRACP-positive MNC formation induced by 1 alpha,25-(OH)2D3, whereas the glucocorticoid alone had no effect on it. In contrast, osteoblastic MC3T3-E1 cells failed to induce TRACP-positive cells in the cocultures. Another bone marrow-derived stromal cell line ST2 also induced TRACP-positive MNC formation in the cocultures in response to 1 alpha,25-(OH)2D3 and dexamethasone. Salmon calcitonin enhanced cAMP production in the cocultures only when TRACP-positive cells were formed. Autoradiographic studies demonstrated that [125I]calcitonin specifically bound to TRACP-positive cells formed in the cocultures. When spleen cells and either MC3T3-G2/PA6 or ST2 cells were cocultured on sperm whale dentine slices in the presence of 1 alpha,25-(OH)2D3 and dexamethasone, numerous resorption lacunae were formed. These results show that the two bone marrow-derived stromal cell lines can support osteoclast-like cell differentiation in cocultures with spleen cells.
在我们之前报道从小鼠胎儿颅骨新鲜分离的富含成骨细胞群体与小鼠脾细胞共培养时，会响应1α,25 - 二羟基维生素D3 [1α,25-(OH)2D3]形成破骨细胞样多核细胞（MNCs）之后，我们研究了在诱导破骨细胞样细胞形成过程中，此类原代成骨细胞样细胞是否可被已建立的细胞系替代。我们首先使用了同时从新生小鼠颅骨建立的两种克隆细胞系。一种是成骨细胞系MC3T3 - E1，另一种是前脂肪细胞系MC3T3 - G2/PA6。在1α,25-(OH)2D3存在的情况下，脾细胞与MC3T3 - G2/PA6细胞共培养时形成了抗酒石酸酸性磷酸酶（TRACP；破骨细胞的标记酶）阳性单核细胞和MNCs。地塞米松极大地增强了1α,25-(OH)2D3诱导的TRACP阳性MNC形成，而单独使用糖皮质激素对此无影响。相比之下，成骨细胞系MC3T3 - E1细胞在共培养中未能诱导出TRACP阳性细胞。另一种骨髓来源的基质细胞系ST2在响应1α,25-(OH)2D3和地塞米松时，也在共培养中诱导出TRACP阳性MNC形成。仅当形成TRACP阳性细胞时，鲑鱼降钙素才增强共培养中的cAMP产生。放射自显影研究表明，[125I]降钙素特异性结合共培养中形成的TRACP阳性细胞。当脾细胞与MC3T3 - G2/PA6或ST2细胞在1α,25-(OH)2D3和地塞米松存在的情况下在抹香鲸牙本质切片上共培养时，形成了大量吸收陷窝。这些结果表明，这两种骨髓来源的基质细胞系在与脾细胞共培养时可支持破骨细胞样细胞分化。
