Hallmarks of human "immunosenescence": adaptation or dysregulation?
Hallmarks of human "immunosenescence": adaptation or dysregulation?
复制标题
DOI：
10.1186/1742-4933-9-15
复制
发表时间：
2012-07-25
期刊：
影响因子：
--
通讯作者：
Pawelec G
中科院分区：
文献类型：
--
作者：
Pawelec G
免疫衰老是导致免疫失调的内在衰老过程，还是个体对病原体暴露的适应性反应？骨髓免疫细胞输出和胸腺退化的年龄相关性差异提示前者。免疫衰老的公认特征（外周naïve T细胞，特别是CD8+细胞的数量和百分比减少，记忆T细胞的积累，特别是晚期分化的CD8+细胞）表明是后者，这被认为是naïve细胞库随着时间的推移与病原体接触而消耗的结果，并将其转化为记忆细胞，这是适应性免疫的基础。在生命早期开始的胸腺退化限制了幼稚细胞的产生，因此成年人被认为在很大程度上依赖于主要在青春期前产生的naïve细胞库。因此，这些免疫衰老的标志将明显受到个体暴露于病原体的历史的影响。可以预测，在现代工业化人口中，抗原“压力源”的累积效应将低于卫生条件较差的社会，而内在过程在不同人口中可能更为相似。因此，确定这些压力源并采取措施消除其影响可能导致免疫衰老延迟，并大大有助于改善公众健康。在这里，我将讨论与这一预测有关的一些现有数据。
Is immunosenescence an intrinsic ageing process leading to dysregulation of immunity or an adaptive response of the individual to pathogen exposure? Age-associated differences in bone marrow immune cell output and thymic involution suggest the former. Accepted hallmarks of immunosenescence (decreased numbers and percentages of peripheral naïve T cells, especially CD8 + cells, and accumulations of memory T cells, especially late-stage differentiated CD8+ cells) suggest the latter, viewed as the result of depletion of the reservoir of naïve cells over time by contact with pathogens and their conversion to memory cells, the basis of adaptive immunity. Thymic involution beginning early in life limits the generation of naive cells such that the adult is believed to rely to a great extent on the naïve cell pool produced mostly before puberty. Thus, these hallmarks of immunosenescence would be markedly affected by the history of the individual´s exposure to pathogens. It would be predicted that in modern industrialized populations, the cumulative effects of antigenic “stressors” would be lower than in less hygienic societies, whereas intrinsic processes might be more similar in different populations. Identifying such stressors and taking steps to nullify their impact could therefore result in delayed immunosenescence and contribute significantly to improving public health. Here, I discuss some of the available data bearing on this prediction.
登录
查看更多内容
DOI：
10.1186/1742-4933-4-2
发表时间：
2007-03-21
期刊：
Immunity & ageing : I & A
影响因子：
--
作者：
Vasto, Sonya;Colonna-Romano, Giuseppina;Pawelec, Graham
通讯作者：
Pawelec, Graham
影响因子：
4.4
作者：
Derhovanessian, Evelyna;Maier, Andrea B.;Pawelec, Graham
通讯作者：
Pawelec, Graham
影响因子：
4.5
作者：
Wikby, Anders;Mansson, Ingrid A.;Nilsson, Sven E.
通讯作者：
Nilsson, Sven E.
可能影响免疫衰老的因素：评估。
影响因子：
7.9
作者：
Ongradi, Joseph;Kovesdi, Valeria
通讯作者：
Kovesdi, Valeria
影响因子：
5.3
作者：
Wikby, Anders;Nilsson, Bengt-Olof;Johansson, Boo
通讯作者：
Johansson, Boo