Format

Send to

Choose Destination
See comment in PubMed Commons below
Mech Ageing Dev. 2011 Apr;132(4):187-94. doi: 10.1016/j.mad.2011.03.005. Epub 2011 Mar 29.

Impaired in vivo CD4+ T cell expansion and differentiation in aged mice is not solely due to T cell defects: decreased stimulation by aged dendritic cells.

Author information

1
Departamento de Biologia Celular e Molecular (FABIO) and Instituto de Pesquisas Biom├ędicas, PUCRS, Av. Ipiranga, Porto Alegre, RS, Brazil.

Abstract

CD4+ T cells regulate humoral and cell-mediated immune responses, which are progressively impaired in aging, resulting in susceptibility to infections and cancer. Dendritic cells (DCs) are major activators of T cells, providing signals that drive their expansion and differentiation. In this study, we asked if decreased CD4+ T cell responses were influenced by the age of DCs rather than being exclusively due to T cell defects. Old T cells transferred to young recipients expanded and differentiated similarly to young T cells. However, aged recipients were poor stimulators of both old and young T cells, which failed to acquire CD44 expression and produce interferon gamma (IFN-╬│). DCs in aged hosts expressed fewer MHC-peptide complexes. The CD86 expression in the DCs of both hosts was similar; however, CD40 levels were reduced in old DCs. Finally, old DCs failed to produce inflammatory cytokines in response to LPS. Our results indicate that the impairment of aged CD4+ T cell function is intimately related to multiple alterations in aged DCs, rather than being caused solely by intrinsic T cell defects, suggesting that the function of aged T cells may be partially rescued in vivo when appropriate stimulation is applied. These findings are relevant to vaccination design for elderly populations.

PMID:
21453718
DOI:
10.1016/j.mad.2011.03.005
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center