Sebastiani Silvia, Albanesi Cristina, De Pità Ornella, Puddu Pietro, Cavani Andrea, Girolomoni Giampiero
Istituto Dermopatico dell'Immacolata, IRCCS, Roma, Italy.
Arch Dermatol Res. 2002 Jan;293(11):552-9. doi: 10.1007/s00403-001-0276-9.
Chemokines are important mediators of immune-mediated skin diseases. Allergic contact dermatitis (ACD) is the most thoroughly investigated T cell-mediated disorder because of the ability to easily reproduce the lesions in humans and the availability of an excellent mouse model. Migration of dendritic cells from the skin to lymph nodes is absolutely required for induction of hapten sensitization, and depends upon expression of CCR7 by mature dendritic cells and SLC in the lymph nodes. During expression of ACD, recruitment of T lymphocytes is driven by chemokines exposed on the surface of endothelial cells or released by activated resident skin cells such as mast cells, fibroblasts and keratinocytes. Chemokines are produced in a coordinated and sequential manner, with IL-8 and RANTES induced by TNF-alpha during early stages, and MCP-1, IP-10, Mig, I-TAC, I-309 and MDC induced by IFN-gamma during later stages. Infiltrating monocytes, dendritic cells and T cells are additional sources of chemokines for further leukocyte accumulation. Distinct T cell subsets express different chemokine receptors, with type 2 cells mostly attracted by eotaxin, MDC, TARC and I-309, and type 1 cells sensitive to IP-10, Mig, I-TAC, RANTES and MIP-1beta. MCP-1 is effective on both subsets. T regulatory cells, which inhibit dendritic cell function and are probably involved in the termination of ACD, are sensitive to MCP-1, MIPs and TARC, but express high levels of CCR8 and are more specifically attracted by I-309. Targeting chemokines and chemokine receptors may offer new opportunities for therapeutic interventions in ACD and other chronic inflammatory skin diseases.
趋化因子是免疫介导性皮肤病的重要介质。过敏性接触性皮炎(ACD)是研究最为深入的T细胞介导性疾病,因为它能够在人体中轻易再现皮损,并且有出色的小鼠模型可供使用。树突状细胞从皮肤迁移至淋巴结对于诱导半抗原致敏绝对必要,这取决于成熟树突状细胞上CCR7的表达以及淋巴结中的SLC。在ACD发病过程中,T淋巴细胞的募集由内皮细胞表面暴露的趋化因子或由活化的驻留皮肤细胞(如肥大细胞、成纤维细胞和角质形成细胞)释放的趋化因子驱动。趋化因子以协调且有序的方式产生,早期阶段由TNF-α诱导产生IL-8和RANTES,后期阶段由IFN-γ诱导产生MCP-1、IP-10、Mig、I-TAC、I-309和MDC。浸润的单核细胞、树突状细胞和T细胞是趋化因子的额外来源,可促使更多白细胞聚集。不同的T细胞亚群表达不同的趋化因子受体,2型细胞主要被嗜酸性粒细胞趋化因子、MDC、TARC和I-309吸引,1型细胞对IP-10、Mig、I-TAC、RANTES和MIP-1β敏感。MCP-1对这两个亚群均有效。T调节细胞抑制树突状细胞功能,可能参与ACD的终止,它们对MCP-1、MIPs和TARC敏感,但表达高水平的CCR8,更特别地被I-309吸引。针对趋化因子和趋化因子受体可能为ACD和其他慢性炎症性皮肤病的治疗干预提供新机会。