Division of Basic and Clinical Immunology, Med. Sci. I C-240A, University of California, Irvine 92697, CA, USA.
Ageing Res Rev. 2011 Jul;10(3):336-45. doi: 10.1016/j.arr.2010.06.004. Epub 2010 Jul 7.
Aging is a paradox of reduced immunity and chronic inflammation. Dendritic cells are central orchestrators of the immune response with a key role in the generation of immunity and maintenance of tolerance. The functions of DCs are compromised with age. There is no major effect on the numbers and phenotype of DC subsets in aged subjects; nevertheless, their capacity to phagocytose antigens and migrate is impaired with age. There is aberrant cytokine secretion by various DC subsets with CDCs secreting increased basal level of pro-inflammatory cytokines but the response on stimulation to foreign antigens is decreased. In contrast, the response to self-antigens is increased suggesting erosion of peripheral self tolerance. PDC subset also secretes reduced IFN-α in response to viruses. The capacity of DCs to prime T cell responses is also affected. Aging thus has a profound affect on DC functions. Present review summarizes the effect of advancing age on DC functions in humans in the context of both immunity and tolerance.
衰老是免疫功能降低和慢性炎症的矛盾。树突状细胞是免疫反应的核心协调者，在免疫的产生和耐受的维持中起着关键作用。随着年龄的增长，DC 的功能受到损害。在老年患者中，DC 亚群的数量和表型没有明显变化；然而，它们摄取抗原和迁移的能力随着年龄的增长而受损。各种 DC 亚群的细胞因子分泌异常，中央型 DC 分泌增加基础水平的促炎细胞因子，但对外来抗原刺激的反应减少。相反，对自身抗原的反应增加，提示外周自身耐受的侵蚀。PDC 亚群对病毒的 IFN-α 反应也减少。DC 诱导 T 细胞反应的能力也受到影响。因此，衰老对 DC 功能有深远的影响。本综述总结了年龄增长对人类 DC 功能的影响，包括免疫和耐受两个方面。
