Review Article | Published:

The twilight of immunity: emerging concepts in aging of the immune system

Nature Immunologyvolume 19pages1019 (2018) | Download Citation



Immunosenescence is a series of age-related changes that affect the immune system and, with time, lead to increased vulnerability to infectious diseases. This Review addresses recent developments in the understanding of age-related changes that affect key components of immunity, including the effect of aging on cells of the (mostly adaptive) immune system, on soluble molecules that guide the maintenance and function of the immune system and on lymphoid organs that coordinate both the maintenance of lymphocytes and the initiation of immune responses. I further address the effect of the metagenome and exposome as key modifiers of immune-system aging and discuss a conceptual framework in which age-related changes in immunity might also affect the basic rules by which the immune system operates.

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I thank past and present members of the Nikolich lab and the UA Department of Immunobiology for collaborative work that led to some of the concepts crystallized in this work; E. Goldberg for suggestions; I. Jeftic, M. Jergovic, M. Smithey and H. Thompson for help with illustrations and critical perusal of the manuscript; and M. Kuhns for the suggestion that rules of immune system might change with aging and for critical perusal of the manuscript. Supported by the US Public Health Service (AG020719, AG048021 and AG053259), the US National Institutes of Health (HHSN 272201100017 C and HHSN272200900059C) and the Elizabeth Bowman Endowed Professorship in Medical Science.

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  1. Department of Immunobiology and the Arizona Center on Aging, University of Arizona College of Medicine–Tucson, Tucson, AZ, USA

    • Janko Nikolich-Žugich


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