Taimi M, Château M T, Marti J, Pacaud M
Laboratoire de Biologie Cellulaire, INSERM U65, Université de Montpellier II, France.
Differentiation. 1990 Oct;45(1):55-60. doi: 10.1111/j.1432-0436.1990.tb00457.x.
We have studied the expression of vimentin in the human histiocytic lymphoma cell line U937, induced to differentiate along the monocyte/macrophage pathway. Normal monocytes possess a network of vimentin intermediate filaments (IFs) at all stages of maturation. The undifferentiated U937 leukemia cells contain very low amounts of vimentin, but express a conspicuous IF network when exposed to phorbol myristate acetate. In parallel, they acquire functional properties typical of cells of the monocyte lineage. These concomitant variations suggest that vimentin IFs could play a role in the process of differentiation. However, we observed that all-trans-retinoic acid and 1,25-dihydroxyvitamin D3 confer monocyte-like properties upon U937 cells without inducing vimentin expression. We obtained increased phenotypic changes, yet in the absence of a vimentin network, by combining the effects of both inducers. These results show that vimentin expression is not crucial for the acquisition of some of the functions characteristic of the monocyte/macrophage lineage.
我们研究了人组织细胞淋巴瘤细胞系U937中波形蛋白的表达情况，该细胞系被诱导沿单核细胞/巨噬细胞途径分化。正常单核细胞在成熟的各个阶段都拥有波形蛋白中间丝（IFs）网络。未分化的U937白血病细胞含有极少量的波形蛋白，但在暴露于佛波酯肉豆蔻酸酯乙酸盐时会表达出明显的IF网络。与此同时，它们获得了单核细胞谱系细胞典型的功能特性。这些伴随的变化表明波形蛋白IFs可能在分化过程中起作用。然而，我们观察到全反式维甲酸和1,25 - 二羟基维生素D3赋予U937细胞单核细胞样特性，但不诱导波形蛋白表达。通过结合两种诱导剂的作用，我们获得了增强的表型变化，但没有波形蛋白网络。这些结果表明，波形蛋白表达对于获得单核细胞/巨噬细胞谱系的某些特征功能并非至关重要。
