Elliott M J, Strasser A, Metcalf D
Cancer Research Unit, Walter and Eliza Hall Institute of Medical Research, Royal Melbourne Hospital, Victoria, Australia.
J Immunol. 1991 Nov 1;147(9):2957-63.
Peritoneal and pleural cells from mice transgenic for GM-CSF were studied with regard to their phenotype and functional capacity, and compared with cells from normal littermates. Transgenic mice showed markedly elevated peritoneal and pleural cell counts compared with littermates, and a significantly higher proportion of cells in the transgenic populations were macrophage in phenotype. Transgenic macrophages were larger than the littermate cells, showing abundant foamy cytoplasm and enhanced spreading on plastic. Analysis by flow cytometry showed a more than sixfold increased expression of the macrophage activation markers MAC-2 and MAC-3, but not other markers, on transgenic macrophages. Superoxide production was measured in whole cell populations, both in their basal state and in response to particulate (zymosan) and soluble (PMA) stimuli. Both basal and stimulated superoxide production were markedly elevated in transgenic mice of 12 wk of age, with the largest differences seen in response to PMA. In younger mice, however, only PMA-stimulated superoxide production was significantly greater in transgenic macrophages than in littermate cells and levels of superoxide were generally lower than those seen in 12-wk-old mice. These findings suggest that the enhanced functional capacity of transgenic cells is a maturation-dependent event. In contrast to these findings, drug-dependent cytotoxicity assays performed on cells from 12-wk-old mice revealed no significant differences in killing capacity between the two mouse strains. Taken together these data indicate a selective rather than uniform functional up-regulation in transgenic macrophages compared with their littermates, with a time scale suggestive of a maturational rather than activation process. These findings may provide an indication of the functional macrophage phenotype resulting from long term exposure to GM-CSF in vivo, and help to explain the macrophage-associated pathology seen in GM-CSF-transgenic mice.
对转基因表达粒细胞-巨噬细胞集落刺激因子（GM-CSF）的小鼠的腹膜和胸膜细胞的表型和功能能力进行了研究，并与正常同窝小鼠的细胞进行了比较。与同窝小鼠相比，转基因小鼠的腹膜和胸膜细胞计数明显升高，并且转基因群体中巨噬细胞表型的细胞比例显著更高。转基因巨噬细胞比同窝小鼠的细胞更大，显示出丰富的泡沫状细胞质并在塑料表面上的铺展能力增强。流式细胞术分析显示，转基因巨噬细胞上巨噬细胞活化标志物MAC-2和MAC-3的表达增加了六倍以上，但其他标志物没有增加。在整个细胞群体中测量了超氧化物的产生，包括基础状态以及对颗粒（酵母聚糖）和可溶性（佛波酯，PMA）刺激的反应。12周龄转基因小鼠的基础和刺激后的超氧化物产生均明显升高，对PMA刺激的反应差异最大。然而，在较年轻的小鼠中，只有PMA刺激的转基因巨噬细胞中超氧化物产生明显高于同窝小鼠的细胞，并且超氧化物水平通常低于12周龄小鼠。这些发现表明转基因细胞功能能力的增强是一个依赖成熟的事件。与这些发现相反，对12周龄小鼠细胞进行的药物依赖性细胞毒性试验显示，两种小鼠品系之间的杀伤能力没有显著差异。综合这些数据表明，与同窝小鼠相比，转基因巨噬细胞存在选择性而非一致的功能上调，其时间尺度提示是成熟过程而非激活过程。这些发现可能提示了长期体内暴露于GM-CSF所导致的功能性巨噬细胞表型，并有助于解释GM-CSF转基因小鼠中所见的巨噬细胞相关病理学现象。
