Kerrigan Ann M, Dennehy Kevin M, Mourão-Sá Diego, Faro-Trindade Inês, Willment Janet A, Taylor Philip R, Eble Johannes A, Reis e Sousa Caetano, Brown Gordon D
Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa.
J Immunol. 2009 Apr 1;182(7):4150-7. doi: 10.4049/jimmunol.0802808.
CLEC-2 is a member of the "dectin-1 cluster" of C-type lectin-like receptors and was originally thought to be restricted to platelets. In this study, we demonstrate that murine CLEC-2 is also expressed by peripheral blood neutrophils, but only weakly by bone marrow or elicited inflammatory neutrophils. On circulating neutrophils, CLEC-2 can mediate phagocytosis of Ab-coated beads and the production of proinflammatory cytokines, including TNF-alpha, in response to the CLEC-2 ligand, rhodocytin. CLEC-2 possesses a tyrosine-based cytoplasmic motif similar to that of dectin-1, and we show using chimeric analyses that the activities of this receptor are dependent on this tyrosine. Like dectin-1, CLEC-2 can recruit the signaling kinase Syk in myeloid cells, however, stimulation of this pathway does not induce the respiratory burst. These data therefore demonstrate that CLEC-2 expression is not restricted to platelets and that it functions as an activation receptor on neutrophils.
CLEC-2是C型凝集素样受体“dectin-1簇”的成员,最初被认为仅存在于血小板中。在本研究中,我们证明小鼠CLEC-2在外周血中性粒细胞中也有表达,但在骨髓或炎症诱导的中性粒细胞中表达较弱。在循环中的中性粒细胞上,CLEC-2可介导抗体包被珠子的吞噬作用,并在CLEC-2配体红树毒素的作用下产生促炎细胞因子,包括肿瘤坏死因子-α。CLEC-2具有与dectin-1类似的基于酪氨酸的细胞质基序,我们通过嵌合分析表明该受体的活性依赖于该酪氨酸。与dectin-1一样,CLEC-2可在髓样细胞中募集信号激酶Syk,然而,该信号通路的激活并不会诱导呼吸爆发。因此,这些数据表明CLEC-2的表达并不局限于血小板,并且它在中性粒细胞上作为一种激活受体发挥作用。