Megiovanni Anna Maria, Sanchez Françoise, Gluckman Jean Claude, Rosenzwajg Michelle
Institut National de la Recherche Scientifique - Université Paris 7 EMI-0013 and laboratoire d'Immunologie Cellulaire et Immunopathologie de l'Ecole Pratique des Hautes Etudes, Institut Universitaire d'Hématologie, hôpital Saint-Louis, Paris, France.
Eur Cytokine Netw. 2004 Apr-Jun;15(2):126-34.
Monocyte-derived dendritic cells (DCs) were used as an in vitro model of myeloid DCs in order to determine a minimum marker pattern with which to characterize and distinguish different stages of DC activation and maturation. Phenotypic changes induced on immature DCs by two prototypic stimuli, poly I:C and CD40 ligation, were first examined. Both elicited HLA-DR, CD40, CD86 and CXCR4 upregulation, and CCR5 downregulation, but only CD40 ligand-stimulated DCs became CD83(+)\CCR7(+), whereas poly I:C-stimulated DCs expressed lower CD83 levels and were mostly CCR7(--). CD40 ligation and poly I:C elicited increased production of inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor-alpha, of IL-10 and the CCL5 chemokine, but profiles differed as to higher IL-10, IL-12 and CCL22 (a CCR4 ligand important for T cell recruitment) levels for the former, and of CCL4 and CCL5 for the latter. Thus, a limited set of phenotypic markers, cytokine and chemokine production assays, may be used to distinguish the three stages in the life of DCs: immaturity, activation and full maturation. The ability of purified protein derivative-loaded DCs to stimulate autologous T cells to produce IL-2, IL-4 and interferon-gamma indeed depended on their activation stage and endocytic activity, which decreased upon maturation. We then examined whether ligation of CD4, CCR5 and\or CXCR4, the receptor and coreceptors of human immunodeficiency virus envelope gp120, respectively, affected DC activation or maturation, neither a monoclonal antibody to the gp120-binding site on CD4 nor CCL5 nor CXCL12, the natural ligands of CCR5 and CXCR4, respectively, nor gp120 altered the DC activation and maturation processes.
为了确定用于表征和区分树突状细胞（DC）激活和成熟不同阶段的最小标志物模式，将单核细胞衍生的DC用作髓样DC的体外模型。首先研究了两种典型刺激物聚肌胞苷酸（poly I:C）和CD40连接对未成熟DC诱导的表型变化。两者均引起HLA-DR、CD40、CD86和CXCR4上调，以及CCR5下调，但只有CD40配体刺激的DC变成CD83(+) \CCR7(+)，而poly I:C刺激的DC表达较低的CD83水平且大多为CCR7(–)。CD40连接和poly I:C引起炎性细胞因子白细胞介素（IL）-6和肿瘤坏死因子-α、IL-10以及CCL5趋化因子的产生增加，但两者的谱不同，前者的IL-10、IL-12和CCL22（对T细胞募集很重要的CCR4配体）水平较高，而后者的CCL4和CCL5水平较高。因此，一组有限的表型标志物、细胞因子和趋化因子产生测定法可用于区分DC生命周期中的三个阶段：未成熟、激活和完全成熟。负载纯化蛋白衍生物的DC刺激自体T细胞产生IL-2、IL-4和干扰素-γ的能力确实取决于它们的激活阶段和内吞活性，而内吞活性在成熟时会降低。然后我们研究了分别作为人类免疫缺陷病毒包膜糖蛋白gp120的受体和共受体的CD4、CCR5和\或CXCR4的连接是否影响DC的激活或成熟，结果发现，针对CD4上gp120结合位点的单克隆抗体、CCR5和CXCR4的天然配体CCL5和CXCL12以及gp120均未改变DC的激活和成熟过程。
