IL6 and major depressive disorder: The levels of tumor necrosis factor-alpha (TNF-a) interleukin-1 beta (IL-1b) (Rossi et al., 2017), and interleukin 6 (IL-6) (Brenner et al., 2018) were found to be associated with depression severity as measured by BDI II, while levels of Interleukin-2 (IL-2) were found to be correlated with anxiety measured by STAI-state.