IL7 and viral infectious disease: Clear evidence exists for the therapeutic potential of IL-7 administration on thymic regeneration, centered on the beneficial effects of IL-7 on increasing progenitor T cells in the thymus and subsequently expanding circulating naïve T cells in viral infection setting (143); however, IL-7 therapy only transiently increased naïve T cells in the aged setting in rhesus macaques, with a more prominent and long lasting effect in the memory T cell compartment (144).