Kreipe H, Radzun H J, Heidorn K, Parwaresch M R, Verrier B, Müller R
Differentiation. 1986;33(1):56-60. doi: 10.1111/j.1432-0436.1986.tb00410.x.
In vitro differentiation studies using the bipotential human leukemia cell line, HL60, have indicated that high levels of expression of two proto-oncogenes, c-fos and c-fms, are restricted to the myelomonocytic lineage. No such expression has been detected in induced granulocytic cells. In striking contrast to these observations, we found that c-fos mRNA levels are very high in purified human granulocytes, but barely detectable in blood monocytes and tissue macrophages. Human granulocytes contain, however, relatively low levels of c-fos protein, indicating that c-fos mRNA is inefficiently translated or that the protein is rapidly degraded in these cells. In closer agreement with the in vitro results, the level of the expression of c-fms is high in purified blood monocytes and undetectable in granulocytes. We found, however, that the evolution of monocytes into tissue macrophages is accompanied by a significant decrease in c-fms expression, suggesting that the function of c-fms is restricted to specific stages of monocytic differentiation. Our observations also show that results obtained using in vitro differentiation systems have to be regarded with caution, since they may not reflect the in vivo situation.
利用双潜能人白血病细胞系HL60进行的体外分化研究表明，两种原癌基因c-fos和c-fms的高水平表达仅限于骨髓单核细胞系。在诱导的粒细胞中未检测到这种表达。与这些观察结果形成鲜明对比的是，我们发现c-fos mRNA水平在纯化的人粒细胞中非常高，但在血液单核细胞和组织巨噬细胞中几乎检测不到。然而，人粒细胞中c-fos蛋白水平相对较低，这表明c-fos mRNA翻译效率低下，或者该蛋白在这些细胞中迅速降解。与体外结果更一致的是，c-fms在纯化的血液单核细胞中表达水平较高，而在粒细胞中未检测到。然而，我们发现单核细胞向组织巨噬细胞的演变伴随着c-fms表达的显著下降，这表明c-fms的功能仅限于单核细胞分化的特定阶段。我们的观察结果还表明，使用体外分化系统获得的结果必须谨慎看待，因为它们可能无法反映体内情况。
