Table II.

Selected experimental treatments to improve T cell immune function in aging

Treatment	Target	Result (reference)
Deglycosylation of T cell   surface molecules in mice	CD43, CD45 and   other surface molecules	Improved signaling, proliferation and   cytokine secretion in both old and young (28, 29)
Treatment with vitamin   E in elderly humans	Cell membrane fluidity   and oxidative stress	Reduced incidence of respiratory   infections in the elderly (30)
Addition of costimulation in mice   (immune adjuvants or   costimulatory antibodies)	Innate immunity/costimulatory pathways	Increased CD4 T cell proliferation   and cytokine production (31)
Caloric restriction in mice and primates	Cellular—naive T cell maintenance,   T cell signaling;   molecular target not known	Mice: Improved CTL function and antigen presentation (32)   Primates: improved naive T cell maintenance and   function (unpublished data)