Kadowaki Norimitsu, Liu Yong-Jun
Department of Hematology and Oncology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Hum Immunol. 2002 Dec;63(12):1126-32. doi: 10.1016/s0198-8859(02)00751-6.
Type I interferons (IFNs) are promptly produced upon invasion of pathogens, and activate a broad range of effector cells in the innate and adaptive immune system. Lin(-)CD4(+)CD11c(-) plasmacytoid dendritic cell precursors (plasmacytoid pre-DCs) produce enormous amounts of type I IFNs in response to viruses and CpG DNA, thus corresponding to the previously described but not fully defined natural type I IFN-producing cells (IPCs). Plasmacytoid pre-DCs strongly express toll-like receptor (TLR) 7 and TLR9, in contrast to monocytes, which mainly express TLR1, 2, 4, 5, and 8, suggesting that these two DC precursors recognize different microbial molecules and that they may have developed through different evolutionary trails. Three different stimuli, CpG DNA plus CD40 ligand, interleukin-3 (IL-3), and herpes simplex virus, stimulate plasmacytoid pre-DCs to differentiate into DCs that induce distinct types of T helper cells, i.e., Th1, Th2, and IFN-gamma- and IL-10-producing T cells, respectively. The remarkable versatility of plasmacytoid pre-DCs distinguishes them from other cell types in the immune system that have only limited functions, and suggests that these cells may play a key role in integrating the innate and adaptive aspects of various immune responses.
I型干扰素（IFN）在病原体入侵后迅速产生，并激活先天性和适应性免疫系统中的多种效应细胞。Lin(-)CD4(+)CD11c(-)浆细胞样树突状细胞前体（浆细胞样前DC）在响应病毒和CpG DNA时会产生大量I型干扰素，因此与先前描述但尚未完全定义的天然I型干扰素产生细胞（IPC）相对应。与主要表达TLR1、2、4、5和8的单核细胞不同，浆细胞样前DC强烈表达Toll样受体（TLR）7和TLR9，这表明这两种DC前体识别不同的微生物分子，并且它们可能通过不同的进化途径发展而来。三种不同的刺激，即CpG DNA加CD40配体、白细胞介素-3（IL-3）和单纯疱疹病毒，刺激浆细胞样前DC分化为分别诱导不同类型辅助性T细胞的DC，即Th1、Th2以及产生IFN-γ和IL-10的T细胞。浆细胞样前DC具有显著的多功能性，这使其有别于免疫系统中功能有限的其他细胞类型，并表明这些细胞可能在整合各种免疫反应的先天性和适应性方面发挥关键作用。
