Regulation of 15-lipoxygenase expression in lung epithelial cells by interleukin-4
Regulation of 15-lipoxygenase expression in lung epithelial cells by interleukin-4
复制标题
DOI：
10.1042/bj3180305
复制
发表时间：
1996-08-15
影响因子：
4.1
通讯作者：
Habenicht, AJR
中科院分区：
文献类型：
--
作者：
Brinckmann, R;Topp, MS;Habenicht, AJR
我们研究了15-脂氧合酶基因在各种永久性哺乳动物细胞系中对白细胞介素-IL和-13的反应，发现当在标准条件下培养时，测试的细胞系均不表达5-、12-或15-脂氧合酶。然而，当肺癌细胞系A549维持在白细胞介素的存在下24小时或更长时间，我们观察到一个主要的诱导15-脂氧合酶，如15-脂氧合酶mRNA的定量，免疫组化，免疫印迹分析和酶活性测定。这种效应是15-脂氧合酶特异性的，因为5-和12-脂氧合酶的表达仍然检测不到。白细胞介素-4处理的时间过程表明，15-脂氧合酶mRNA和功能蛋白在48 h后达到最大积累。结合研究表明，A549细胞表达约2100个高亲和力的白细胞介素-4结合位点每个细胞。白细胞介素-4突变体Y124 D能够与白细胞介素-4受体结合，但不能触发受体活化，抵消了野生型细胞因子的作用。其他细胞系，包括几个上皮细胞和各种单核细胞系表达相当数量的白细胞介素-4受体，不表达15-脂氧合酶时，刺激白细胞介素-4。这些数据表明，A549细胞选择性表达15-脂氧合酶时，白细胞介素-4和-13刺激。白细胞介素-4/13受体的激活对于15-脂氧合酶基因表达似乎是强制性的，但不是充分的。
We have studied the expression of the 15-lipoxygenase gene in various permanent mammalian cell lines in response to interleukins-il and -13, and found that none of the cell lines tested expressed 5-, 12- or 15-lipoxygenase when cultured under standard conditions. However, when the lung carcinoma cell line A549 was maintained in the presence of either interleukin for 24 h or more, we observed a major induction of 15-lipoxygenase, as indicated by quantification of 15-lipoxygenase mRNA, by immunohistochemistry, by immunoblot analysis and by enzyme activity assays. This effect was 15-lipoxygenase-specific, since expression of 5- and 12-lipoxygenases remained undetectable. The time course of interleukin-4 treatment indicated maximal accumulation of both 15-lipoxygenase mRNA and functional protein after 48 h. Binding studies revealed that A549 cells express about 2100 high-affinity interleukin-4 binding sites per cell. The interleukin-4 mutant Y124D, which is capable of binding to the interleukin-4 receptor but is unable to trigger receptor activation, counteracted the effect of the wild-type cytokine. Other cell lines, including several epithelial cells and various monocytic cell lines expressing comparable numbers of interleukin-4 receptors, did not express 15-lipoxygenase when stimulated with interleukin-4. These data indicate that A549 cells selectively express 15-lipoxygenase when stimulated with interleukins-4 and -13. The activation of the interleukin-4/13 receptor(s) appears to be mandatory, but not sufficient, for 15-lipoxygenase gene expression.