Expression and regulation of the orphan receptor RDC1 and its putative ligand in human dendritic and B cells
Expression and regulation of the orphan receptor RDC1 and its putative ligand in human dendritic and B cells
复制标题
DOI：
10.4049/jimmunol.176.4.2197
复制
发表时间：
2006-02-15
影响因子：
4.4
通讯作者：
Thelen, M
中科院分区：
文献类型：
--
作者：
Infantino, S;Moepps, B;Thelen, M
基于系统发育分析和染色体定位，孤儿受体RDC1被认为是趋化因子受体。在这项研究中，我们使用一种新的特异性单抗，通过测量mRNA水平和受体表达来检测RDC1在白细胞上的表达。mRNA和蛋白水平在单核细胞和B细胞中均较高，在未成熟树突状细胞（DC）中相对较低，并在成熟的最后阶段上调。引人注目的是，在成熟的浆细胞样DC中，mRNA上调，但与蛋白表面表达无关。我们确实报道了cpg激活的浆细胞样DC产生一种推测的RDC1配体，它选择性地下调RDC1，而不是CXCR4对原代人B细胞的作用。研究发现，在B细胞发育和分化过程中，RDC1的表达受到严格调控。在血源性开关记忆B细胞中，RDC1的表达似乎与激活后分化为浆细胞的能力相关，这表明RDC1是记忆B细胞的标记物，而记忆B细胞有能力成为B -分泌细胞。
Based on phylogenetic analysis and chromosomal mapping, the orphan receptor RDC1 was proposed to be a chemokine receptor. 14 In this study we examined the expression of RDC1 on leukocytes by measuring mRNA levels and receptor expression using a new specific mAb. Both mRNA and protein levels were high in monocytes and B cells, relatively low on immature dendritic cells (DC), and up-regulated during final stages of maturation. Strikingly, in mature plasmacytoid DC the mRNA was up-regulated, but did not correlate with protein surface expression. We indeed report that CpG-activated plasmacytoid DC produce a putative ligand for RDC1, which selectively down-regulates RDC1, but not CXCR4 on primary human B cells. RDC1 expression was found to be tightly regulated during B cell development and differentiation. In blood-derived switch memory B cells, the expression of RDC1 appeared to correlate with the ability to differentiate into plasma cells upon activation, suggesting that RDC1 is a marker for memory B cells, which are competent to become Ab-secreting cells.