Postmitotic osteoclast precursors are mononuclear cells which express macrophage-associated phenotypes.
Postmitotic osteoclast precursors are mononuclear cells which express macrophage-associated phenotypes.
复制标题
有丝分裂后破骨细胞前体是表达巨噬细胞相关表型的单核细胞。
作者：
N. Takahashi;N. Udagawa;S. Tanaka;H. Murakami;I. Owan;T. Tamura;T. Suda
我们先前证明，在小鼠成骨细胞和脾细胞的共培养物中，破骨细胞样多核细胞在第4-6天（6天共培养期的最后2天）与羟基脲一起加入1 α，25-二羟基维生素D3[1 α，25（OH）2D 3]后6天内形成。使用这种共培养系统，在有丝分裂后破骨细胞前体分化为破骨细胞期间，检查了巨噬细胞相关表型（如非特异性酯酶（NSE）和Mac-1，Mac-2和F4/80抗原）的时间变化，并在第4天加入1 α，25（OH）2D 3（10 nM）诱导破骨细胞。通过使用125 I标记的鲑鱼CT通过放射自显影检查降钙素受体（CTR）的表达来评估破骨细胞分化。在加入1 α，25（OH）2D 3后12小时内，首先在小单核细胞上检测到CTR。CTR阳性单核细胞的数量在24小时达到最大值，此后下降。CTR阳性多核细胞在24小时首次观察到，并在48小时达到最大数量。所有CTR阳性细胞显示抗酒石酸酸性磷酸酶活性（破骨细胞的标志酶）。12小时出现的CTR阳性细胞大多数为NSE和Mac-1、Mac-2抗原阳性，而F4/80抗原阴性。表达NSE和Mac-1的CTR阳性细胞占总CTR阳性单核细胞的比例呈时间依赖性下降。与真正的破骨细胞一样，CTR阳性多核细胞对NSE和Mac-1和F4/80抗原呈阴性，但对Mac-2呈阳性。这些结果表明，有丝分裂后的破骨细胞前体细胞是单核巨噬细胞相关的表型，其中一些迅速消失，在其分化成破骨细胞。
We previously demonstrated that osteoclast-like multinucleated cells were formed within 6 days in cocultures of mouse osteoblastic cells and spleen cells in response to 1 alpha,25-dihydroxyvitamin D3[1 alpha,25(OH)2D3] which was added together with hydroxyurea on Days 4-6 (final 2 days of the 6-day coculture period). Using this coculture system, chronological changes of macrophage-associated phenotypes such as nonspecific esterase (NSE) and antigens to Mac-1, Mac-2, and F4/80 were examined in postmitotic osteoclast precursors during differentiation into osteoclasts induced by 1 alpha,25(OH)2D3 (10 nM) added on Day 4. Osteoclast differentiation was assessed by examining expression of calcitonin receptors (CTRs) by autoradiography using 125I-labeled salmon CT. CTRs were first detected on small mononuclear cells within 12 hr after adding 1 alpha,25(OH)2D3. The number of CTR-positive mononuclear cells attained a maximum at 24 hr and decreased thereafter. CTR-positive multinucleated cells were first observed at 24 hr and reached a maximum population at 48 hr. All CTR-positive cells showed tartrate-resistant acid phosphatase activity (a marker enzyme of osteoclasts). Most of the CTR-positive mononuclear cells which appeared at 12 hr were positive for NSE and antigens to Mac-1 and Mac-2, but negative for F4/80 antigen. The proportion of CTR-positive cells expressing NSE and Mac-1 to total CTR-positive mononuclear cells decreased time dependently. Like authentic osteoclasts, CTR-positive multinucleated cells were negative for NSE and antigens to Mac-1 and F4/80, but positive for Mac-2. These results indicate that postmitotic osteoclast precursors are mononuclear phagocytes with macrophage-associated phenotypes, some of which disappear rapidly during their differentiation into osteoclasts.