Journal of Experimental Medicine, Vol 155, 1870-1875, Copyright © 1982 by Rockefeller University Press
Aging and antimicrobial immunity. Lowered efficiency of protective T cells as a contributing factor for the decreased resistance of senescent mice to listeriosis
PJ Patel
Experimental murine listeriosis was used as a model to investigate the
immunological basis for the age-associated decline in antimicrobial
immunity. The reduced capacity of protective T cells from Listeria- immune
senescent mice to adoptively immunize normal syngeneic recipients could not
be attributed to inhibition of their activity by suppressor cells.
Radiolabeled enriched splenic T cells from Listeria- immune young or
senescent donors exhibited an identical distribution pattern after an
intravenous infusion into young recipients. Moreover, cells from
Listeria-immune young donors showed markedly greater protective capacity
than cells from senescent immune donors whether the cells were transferred
to young or senescent recipients. Dose-response analysis of protective T
cells revealed that in response to immunizing infection (a) senescent mice
generated 10-fold fewer protective T cells, and (b) protective T cells from
senescent mice were 100-fold less efficient than cells from young mice.