Hauswirth A W, Sonneck K, Florian S, Krauth M T, Bohm A, Sperr W R, Valenta R, Schernthaner G H, Printz D, Fritsch G, Buhring H J, Valent P
Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Austria.
Int J Immunopathol Pharmacol. 2007 Apr-Jun;20(2):267-78. doi: 10.1177/039463200702000207.
We recently identified the ectoenzyme CD203c as a novel basophil activation antigen that is upregulated in response to FcepsilonRI cross-linkage. We investigated the effects of various interleukins (ILs) on expression of CD203c on blood basophils using an antibody against CD203c and flow cytometry. Of all cytokines tested, only IL-3 was found to upregulate expression of CD203c on basophils above baseline levels. The effects of IL-3 were dose- and time-dependent (EC(50): 0.1-1 ng/ml) without differences observed between healthy and allergic donors. Whereas anti-IgE induced maximum upregulation of CD203c within 15 minutes, the IL-3-induced upregulation showed a maximum after 180 minutes. IgE-receptor cross-linking resulted in enhanced expression of both CD63 and CD203c, whereas IL-3 enhanced the levels of CD203c without promoting expression of CD63. The IL-3-induced upregulation of CD203c was also observed in highly enriched basophils and was counteracted by a blocking antibody against the alpha chain of the IL-3 receptor (CD123). The IL-3-induced upregulation of CD203c was also found to depend on the presence of calcium. To analyze signaling pathways involved in IL-3-induced upregulation of CD203c, pharmacologic inhibitors were applied. The PI3-kinase inhibitors, wortmannin and LY294002 counteracted the IL-3-induced expression of CD203c, whereas MEK- and PKC inhibitors showed no effects. In conclusion, IL-3 upregulates expression of CD203c on basophils through a specific receptor and via a PI3-kinase-dependent signaling-pathway. Compared to FcepsilonRI-mediated cell activation, IL-3-induced upregulation of CD203c is a late(r) event and is not accompanied by upregulation of CD63.
我们最近鉴定出胞外酶CD203c是一种新型嗜碱性粒细胞活化抗原，其在FcεRI交联反应中上调表达。我们使用抗CD203c抗体和流式细胞术研究了各种白细胞介素（ILs）对血液中嗜碱性粒细胞CD203c表达的影响。在所有测试的细胞因子中，仅发现IL-3可将嗜碱性粒细胞上CD203c的表达上调至基线水平以上。IL-3的作用具有剂量和时间依赖性（半数有效浓度：0.1 - 1 ng/ml），在健康供体和过敏供体之间未观察到差异。抗IgE在15分钟内诱导CD203c最大程度上调，而IL-3诱导的上调在180分钟后达到最大值。IgE受体交联导致CD63和CD203c的表达均增强，而IL-3增强了CD203c的水平，但未促进CD63的表达。在高度富集的嗜碱性粒细胞中也观察到IL-3诱导的CD203c上调，并且被抗IL-3受体α链（CD123）的阻断抗体所抵消。还发现IL-3诱导的CD203c上调依赖于钙的存在。为了分析参与IL-3诱导CD203c上调的信号通路，应用了药理抑制剂。PI3激酶抑制剂渥曼青霉素和LY294002抵消了IL-3诱导的CD203c表达，而MEK和PKC抑制剂则无作用。总之，IL-3通过特定受体并经由PI3激酶依赖性信号通路上调嗜碱性粒细胞上CD203c的表达。与FcεRI介导的细胞活化相比，IL-3诱导的CD203c上调是较晚发生的事件，并且不伴有CD63的上调。
