Mack Matthias, Schneider Martin A, Moll Cordula, Cihak Josef, Brühl Hilke, Ellwart Joachim W, Hogarth Mark P, Stangassinger Manfred, Schlöndorff Detlef
Klinikum, University of Regensburg, Regensburg, Germany.
J Immunol. 2005 Jan 15;174(2):735-41. doi: 10.4049/jimmunol.174.2.735.
Binding of intact Ag is a hallmark of Ag-specific B cells. Apart from B cells, a small number of non-B cells can bind Ag with comparable efficacy as B cells and are found in the peripheral blood, spleen, and bone marrow of mice. This population has been observed for a long time and recently named "Ag-capturing cells." Their identity remained enigmatic. In this study, we show that these cells are basophilic granulocytes. Their ability to capture Ags is dependent on surface IgE receptors and on Ag-specific plasma IgE molecules appearing after immunization. Several surface markers including surface bound IgE, IL-3R, CD45, CD16/32, and the chemokine receptor CCR2 were used to clearly identify these cells. Cross-linkage of surface Igs results in the release of large amounts of IL-4 and IL-6. The data identify basophils as Ag-capturing cells and support the concept of basophils as important regulators of humoral immune responses.
完整抗原的结合是抗原特异性B细胞的一个标志。除了B细胞外，少数非B细胞能以与B细胞相当的效率结合抗原，并且在小鼠的外周血、脾脏和骨髓中被发现。这一细胞群体已被观察了很长时间，最近被命名为“抗原捕获细胞”。它们的身份一直成谜。在本研究中，我们表明这些细胞是嗜碱性粒细胞。它们捕获抗原的能力依赖于表面IgE受体以及免疫后出现的抗原特异性血浆IgE分子。包括表面结合的IgE、IL-3R、CD45、CD16/32和趋化因子受体CCR2在内的几种表面标志物被用于明确鉴定这些细胞。表面免疫球蛋白的交联导致大量IL-4和IL-6的释放。这些数据将嗜碱性粒细胞鉴定为抗原捕获细胞，并支持嗜碱性粒细胞作为体液免疫反应重要调节因子的概念。
