title: Age-related increase in the fraction of CD27-CD4+ T cells and IL-4 production as a feature of CD4+ T cell differentiation in vivo.
abstract: The influence of ageing on phenotype and function of CD4+ T cells was studied by comparing young (19-28 years of age) and aged (75-84 years of age) donors that were selected using the SENIEUR protocol to exclude underlying disease. An age-related increase was observed in the relative number of memory cells, not only on the basis of a decreased CD45RA and increased CD45RO expression, but also on the basis of a decrease in the fraction of CD27+CD4+ T cells. Our observation that the absolute number of CD45RO+CD4+ T cells was increased, while absolute numbers of CD27-CD4+ T cells remained unchanged in aged donors, indicates that the latter subset does not merely reflect the size of the CD45RO+CD4+ T cell pool. The increased fraction of memory cells in the aged was functionally reflected in an increased IL-4 production and T cell proliferation, when cells were activated with the combination of anti-CD2 and anti-CD28, whereas IL-2 production was comparable between both groups. No differences were observed with respect to proliferative T cell responses or IL-2 production using plate-bound anti-CD3 or phytohaemagglutinin (PHA). The observation that IL-4 production correlated with the fraction of memory cells in young donors but not in aged donors suggests different functional characteristics of this subset in aged donors.
authors.affiliation: Section of Immunology, Institute of Ageing and Vascular Research TNO, Leiden, The Netherlands.
authors.forename: E W
authors.initials: EW
authors.lastname: Nijhuis
authors.forename: E J
authors.initials: EJ
authors.lastname: Remarque
authors.forename: B
authors.initials: B
authors.lastname: Hinloopen
authors.forename: T
authors.initials: T
authors.lastname: Van der Pouw-Kraan
authors.forename: R A
authors.initials: RA
authors.lastname: Van Lier
authors.forename: G J
authors.initials: GJ
authors.lastname: Ligthart
authors.forename: L
authors.initials: L
authors.lastname: Nagelkerken
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002454:Cell Differentiation; D006801:Humans; D007156:Immunologic Memory; D007376:Interleukin-2 / Q000096:biosynthesis; D015847:Interleukin-4 / Q000096:biosynthesis*; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008213:Lymphocyte Activation; D010641:Phenotype; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000378:metabolism
chemical_list: D007376:Interleukin-2; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7; D015847:Interleukin-4; D017493:Leukocyte Common Antigens