Fulop Tamas, Larbi Anis, Wikby Anders, Mocchegiani Eugenio, Hirokawa Katsuiku, Pawelec Graham
Immunology Program, Geriatric Division, Research Center on Aging, Faculty of Medicine, University of Sherbrooke, Sherbrooke, Quebec, Canada.
Drugs Aging. 2005;22(7):589-603. doi: 10.2165/00002512-200522070-00005.
The function of the immune system is to maintain body integrity by defending against infections, cancers, autoimmune diseases and inflammation-related chronic diseases. The immune response is known to become defective with aging, leading to decreased longevity and appearance of age-related disease. The most important changes occur in T-cell immunity, and are manifested particularly as altered clonal expansion of cells of limited antigen specificity. The causes of these alterations are multifactorial, and include thymic involution, T-cell subset changes and signal transduction alterations. The clinical consequences of these changes are not well defined, except for their extremely important negative impact on defence against infections, especially by new pathogens, and decreased responses to vaccination. Considering the public health consequences of decreased immune competence in old age, strategies for immune response modulation are desirable to decrease the health burden for the elderly and improve their quality of life.
免疫系统的功能是通过抵御感染、癌症、自身免疫性疾病和炎症相关的慢性疾病来维持身体的完整性。众所周知，免疫反应会随着年龄增长而出现缺陷，导致寿命缩短和与年龄相关疾病的出现。最重要的变化发生在T细胞免疫中，尤其表现为抗原特异性有限的细胞克隆扩增改变。这些改变的原因是多因素的，包括胸腺退化、T细胞亚群变化和信号转导改变。除了它们对抵御感染（尤其是新病原体感染）产生极其重要的负面影响以及疫苗接种反应降低外，这些变化的临床后果尚不清楚。考虑到老年免疫能力下降对公共卫生的影响，需要采取调节免疫反应的策略来减轻老年人的健康负担并提高他们的生活质量。
