Louahed J, Kermouni A, Van Snick J, Renauld J C
Ludwig Institute for Cancer Research, University of Louvain, Brussels, Belgium.
J Immunol. 1995 May 15;154(10):5061-70.
Interleukin 9 (IL-9) is a TH2 cytokine that has been shown to promote the antigen-independent growth of some mouse T helper clones. To characterize the specificity of IL-9-mediated T cell activation, we used a murine T cell clone that could grow with either IL-9 or IL-2. After differential hybridization of a cDNA library, we isolated three genes that were expressed preferentially in the presence of IL-9. Two of them correspond respectively to granzyme A and granzyme B, two proteases expressed by activated T cells. By Northern blot hybridization and functional assays, we found that IL-9 induced the expression of granzyme B in several T cell clones as well as in mast cell lines. In addition, other proteases such as the mouse mast cell proteases were also found to be expressed by IL-9-activated T cell clones. The third IL-9-induced cDNA corresponds to the alpha-chain of the high-affinity receptor for IgE. Several T cell clones expressed this IgE receptor mRNA and were able to bind IgE with high affinity. Taken together, our results indicate that IL-9 induces a mast cell-like phenotype in T cell clones.
白细胞介素9（IL-9）是一种TH2细胞因子，已被证明能促进某些小鼠T辅助细胞克隆的抗原非依赖性生长。为了表征IL-9介导的T细胞活化的特异性，我们使用了一个既能在IL-9也能在IL-2作用下生长的小鼠T细胞克隆。在对cDNA文库进行差异杂交后，我们分离出了三个在IL-9存在下优先表达的基因。其中两个分别对应于颗粒酶A和颗粒酶B，这是两种由活化T细胞表达的蛋白酶。通过Northern印迹杂交和功能分析，我们发现IL-9在几个T细胞克隆以及肥大细胞系中诱导颗粒酶B的表达。此外，还发现其他蛋白酶，如小鼠肥大细胞蛋白酶，也由IL-9活化的T细胞克隆表达。第三个IL-9诱导的cDNA对应于IgE高亲和力受体的α链。几个T细胞克隆表达这种IgE受体mRNA，并能够以高亲和力结合IgE。综上所述，我们的结果表明IL-9在T细胞克隆中诱导出一种肥大细胞样表型。
