Altered T cell signalling in ageing.
T cell responses are altered in the aged in a manner usually interpreted as detrimental to host defences against infectious agents and possibly also against cancer. T cell dysregulation may be caused by any or a combination of stem cell deficits, compromised T cell differentiation, inefficient antigen processing and presentation by antigen presenting cells, suboptimal processing of the antigenic signal by T cells or inability of the T cell to respond appropriately thereafter. This review will focus on altered T cell signalling in ageing, encompassing not only alterations in signal transduction by the antigen-specific T cell receptor, but changes in the balance of positive and negative T cell costimulation and the resultant modified cytokine environment, the response to which is itself altered in ageing.
Pawelec
G
G
Tübingen Ageing and Tumour Immunology Group, Second Department of Internal Medicine, University of Tübingen Medical School, Zentrum für Medizinsche Forschung, Waldhörnlestr. 22, D-72072, Tubingen, Germany. graham.pawelec@uni-tuebingen.de
Hirokawa
K
K
Fülöp
T
T
D000375:Aging / Q000276:immunology*; D000818:Animals; D005786:Gene Expression Regulation; D006801:Humans; D007156:Immunologic Memory / Q000276:immunology; D010641:Phenotype; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D018121:Receptors, Cytokine / Q000276:immunology; D015398:Signal Transduction / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014158:Transcription, Genetic
D011948:Receptors, Antigen, T-Cell; D018121:Receptors, Cytokine