much of what we have learned is owed to the utility of experimental mouse models of aging .
Recent studies <*> have demonstrated mechanisms responsible for age - related declines in the function of CD4 + and CD8 + cells .
Because of the inherent limitations of conducting experiments in humans , much of what we have learned is owed to the utility of experimental mouse models of aging .
Recent studies performed in the mouse have demonstrated mechanisms responsible for age - related declines in the function of CD4 + and CD8 + cells .