T cells and their cytokines in persistent stimulation of the immune system.

Author: Kared H1, Camous X1, Larbi A2.
Affiliation: 1Singapore Immunology Network (SIgN), Immunos Building, 8A Biomedical Grove, Biopolis, Agency for Science Technology and Research (A*STAR), 138648 Singapore, Singapore. 2Singapore Immunology Network (SIgN), Immunos Building, 8A Biomedical Grove, Biopolis, Agency for Science Technology and Research (A*STAR), 138648 Singapore, Singapore. Electronic address: anis_larbi@immunol.a-star.edu.sg.
Conference/Journal: Curr Opin Immunol.
Date published: 2014 May 29
Other: Volume ID: 29C , Pages: 79-85 , Special Notes: doi: 10.1016/j.coi.2014.05.003. , Word Count: 154


Abstract
Age-dependent dysregulations of innate immunity impair effective priming of adaptive immunity. Alteration of helper functions of CD4 T cells during aging prevents them from sustaining cytotoxic responses of CD8 T cells against pathogens. The main characteristics of aged and/or differentiated T cells included telomere erosion, reduction of proliferation, decrease of IL-2 secretion and responsiveness, loss of CD28 and acquisition of cytotoxic properties. Phenotypic and functional modifications associated with aging affect development, differentiation, exhaustion/senescence status, migration, signalisation and metabolism of T lymphocytes. Magnitude and breadth of T cells responses are also regulated by the nature and extent of APCs activation. In our review, we focus on how the T cells age chronologically and within a persistent infection context. The T cell classification is not discussed in details here as it has been recently well documented [1•] however we focus on how cytokines may participate in immune senescence.
Copyright © 2014. Published by Elsevier Ltd.
PMID: 24880502