IL2 and thymus atrophy: Most importantly, thymus atrophy and decreased serum concentration of thymulin, which is necessary especially during maturation of T cells(45,46), and lower levels of growth factors such as IL-2 (T cells) were reported in individuals with decreased serum Zn levels, and a disruption of IL-2 signalling was found when analysing cell cultures, where cellular Zn was depleted using a Zn chelator(47).