Signaling lymphocytic activation molecule (SLAM) receptors have an important role in the development of immune responses because of their roles, for exampe, in NK cell cytotoxicity and cytokine production by NK, T cells and myeloid cells. The SLAM receptor CD244 (2B4, SLAMf4) is expressed on a variety of immune cell types but most of its functions have been examined on NK and T cells. In the present study, we investigated expression and function of CD244 in murine subsets of dendritic cells (DCs). We report that all subsets of murine DCs examined expressed CD244, although the expression levels of CD244 varied between subsets. Splenic and resident mesenteric lymph node (MLN) DCs from CD244(-/-) mice expressed lower levels of CD86 and MHC class II compared with wild-type mice. Upon Toll-like receptor (TLR) stimulation, no differences in surface expression of these molecules were observed between DCs from CD244(-/-) and wild-type mice. However, splenic DCs from CD244(-/-) mice upon stimulation with TLR binding ligands lipopolysaccharide (LPS) and CpG produced significantly higher levels of pro-inflammatory cytokines. In addition, DCs from CD244(-/-) mice elicited increased NK cell activation in vitro. These data add CD244 to a growing list of immuno-modulatory receptors found on DCs.

中文翻译：

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CD244在树突状细胞上表达并调节其功能。

信号淋巴细胞活化分子（SLAM）受体在免疫应答的发展中起重要作用，因为它们在NK细胞的细胞毒性和NK，T细胞和髓样细胞产生的细胞因子中起着重要的作用。SLAM受体CD244（2B4，SLAMf4）在多种免疫细胞类型上表达，但其大部分功能已在NK和T细胞上进行了研究。在本研究中，我们调查了CD244在树突状细胞（DCs）鼠亚型中的表达和功能。我们报告检查的鼠DC的所有子集都表达CD244，尽管CD244的表达水平在子集之间有所不同。与野生型小鼠相比，CD244（-/-）小鼠的脾脏和常驻肠系膜淋巴结（MLN）DC表达的CD86和MHC II类水平较低。受Toll样受体（TLR）刺激后，在来自CD244（-/-）和野生型小鼠的DC之间未观察到这些分子的表面表达差异。但是，用TLR结合配体脂多糖（LPS）和CpG刺激后，来自CD244（-/-）小鼠的脾脏DC产生明显更高水平的促炎细胞因子。此外，来自CD244（-/-）小鼠的DC引起体外NK细胞活化增加。这些数据将CD244添加到DC上不断增加的免疫调节受体列表中。