Immunosenescence: emerging challenges for an ageing population
Tóm tắt
It is now becoming apparent that the immune system undergoes age‐associated alterations, which accumulate to produce a progressive deterioration in the ability to respond to infections and to develop immunity after vaccination, both of which are associated with a higher mortality rate in the elderly. Immunosenescence, defined as the changes in the immune system associated with age, has been gathering interest in the scientific and health‐care sectors alike. The rise in its recognition is both pertinent and timely given the increasing average age and the corresponding failure to increase healthy life expectancy. This review attempts to highlight the age‐dependent defects in the innate and adaptive immune systems. While discussing the mechanisms that contribute to immunosenescence, with emphasis on the extrinsic factors, particular attention will be focused on thymic involution. Finally, we illuminate potential therapies that could be employed to help us live a longer, fuller and healthier life.
Từ khóa
Tài liệu tham khảo
Pawelec G, 1999, Immunosenescence: impact in the young as well as the old?, Mech Ageing Dev, 108, 1
Office for National Statistics. Theme: Population.http://www.statistics.gov.uk/cci/nugget.asp?id=949 2005.
Stephan RP, 1997, Development of B cells in aged mice: decline in the ability of pro‐B cells to respond to IL‐7 but not to other growth factors, J Immunol, 158, 1598, 10.4049/jimmunol.158.4.1598
Kline GH, 1999, B cell maintenance in aged mice reflects both increased B cell longevity and decreased B cell generation, J Immunol, 162, 3342, 10.4049/jimmunol.162.6.3342
LeMaoult J, 1997, Clonal expansions of B lymphocytes in old mice, J Immunol, 159, 3866, 10.4049/jimmunol.159.8.3866
Nicoletti C, 1993, Repertoire diversity of antibody response to bacterial antigens in aged mice. III. Phosphorylcholine antibodies from young and aged mice differ in structure and protective activity against infection with Streptococcus pneumoniae, J Immunol, 150, 543, 10.4049/jimmunol.150.2.543
Godfrey DI, 1993, A developmental pathway involving four phenotypically and functionally distinct subsets of CD3–CD4–CD8– triple‐negative adult mouse thymocytes defined by CD44 and CD25 expression, J Immunol, 150, 4244, 10.4049/jimmunol.150.10.4244
Plum J, 1993, Exogenous IL‐7 promotes the growth of CD3–CD4–CD8–CD44+CD25+/– precursor cells and blocks the differentiation pathway of TCR‐alpha beta cells in fetal thymus organ culture, J Immunol, 150, 2706, 10.4049/jimmunol.150.7.2706