Bm. Lesourd et S. Meaume, CELL-MEDIATED-IMMUNITY CHANGES IN AGING, RELATIVE IMPORTANCE OF CELL SUBPOPULATION SWITCHES AND OF NUTRITIONAL FACTORS, Immunology letters, 40(3), 1994, pp. 235-242
Decreased T-cell functions with ageing have been extensively described
. This review focuses on recent data on changes in T-cell subpopulatio
ns related to ageing and their consequences on T-cell proliferation. I
ncrease of immature T cells CD2(+) CD3(-) is an ageing phenomenon rela
ted to T-cell declining proliferation. Recently it was shown that incr
ease of immature T cells was due to an increase in different subtypes
of the CD2(+) CD3(-) population, double-negative CD2(+) CD4(-) CD8(-)
and double-positive CD2(+) CD4(+) CD8(+) subpopulations, the former be
ing associated with nutritional deficit, the latter with associated di
seases. Other authors have focused on decreases of naive T cells with
parallel increase of memory T cells; such a switch is also relevant to
declining T-cell proliferation. This review focuses on two major fact
ors which influence immune ageing: nutritional parameters and antigen
exposure.