Effect of aging on cytokine production in response to respiratory syncytial virus infection.

In vitro cytokine production in response to respiratory syncytial virus (RSV) and influenza infections was investigated in 11 "young" (mean age, 31 years) and "older" (mean age, 75 years) healthy volunteers by use of interferon (IFN)-gamma ELISPOT and ELISA analysis of cytokines in culture supernatants. Autologous dendritic cells (DCs), derived by culturing adherent peripheral blood mononuclear cells in granulocyte-macrophage colony--stimulating factor and interleukin-4, were used as antigen-presenting cells. Older subjects produced significantly fewer IFN-gamma ELISPOTs in response to RSV than the younger subjects. These results suggest that aging may be associated with a defect in the T cell response to RSV, even when DCs are used to maximize costimulation. This defect in cellular immunity may be related to the increased morbidity observed with RSV infection in elderly persons.