Riva S, Nolli M L, Lutz M B, Citterio S, Girolomoni G, Winzler C, Ricciardi-Castagnoli P
Lepetit Research Center, Marion Merrel Dow Research Institute, Gerenzano, Italy.
J Inflamm. 1996;46(2):98-105.
The primary function of dendritic cells (DC) is the uptake, processing, and presentation of antigens to unprimed T cells, but the regulation of these functions is largely unknown. The study of the signals that maintain DC in a resting state or that drive their activation has been hampered by the difficulties in obtaining pure DC populations. The availability of immortalized DC clones from different tissues (spleen and skin) allowed us to investigate the regulation of cytokine production in response to physiological signals in the absence of contaminating cells. The DC clones exhibited the phenotypical and functional features of DC precursors and could phagocytose, albeit at a low rate, whole bacteria. Heat-inactivated bacteria and bacterial cell wall products were tested for cytokine induction. Lipopolysaccharide, lipoteichoic acid, and gram-negative bacteria were potent inducers of tumor necrosis factor alpha and interleukin 6 release, whereas gram-positive bacteria were less efficient. The results suggest that microbial infections can directly promote cytokine DC release of relevant inflammatory responses as well as in the autocrine activation of DC.
树突状细胞（DC）的主要功能是摄取、处理抗原并将其呈递给未致敏的T细胞，但其这些功能的调节机制很大程度上尚不清楚。由于难以获得纯的DC群体，维持DC处于静息状态或驱动其活化的信号研究受到了阻碍。来自不同组织（脾脏和皮肤）的永生化DC克隆的可得性，使我们能够在不存在污染细胞的情况下，研究DC对生理信号应答时细胞因子产生的调节。DC克隆表现出DC前体的表型和功能特征，并且能够吞噬完整细菌，尽管吞噬率较低。对热灭活细菌和细菌细胞壁产物进行了细胞因子诱导测试。脂多糖、脂磷壁酸和革兰氏阴性菌是肿瘤坏死因子α和白细胞介素6释放的有效诱导剂，而革兰氏阳性菌的诱导效率较低。结果表明，微生物感染可直接促进DC释放相关炎症反应的细胞因子，以及DC的自分泌活化。
