TNF and major depressive disorder: Patients with MDD had significantly higher serum levels of IL-1 beta (0.17 ± 0.13 pg/ml versus 0.09 ± 1.22 pg/ml, p < 0.001) and of TNF-alpha (0.72 ± 0.23 pg/ml versus 0.62 ± 0.22 pg/ml, p = 0.013) than healthy subjects, while levels of hsCRP were similar between groups (Table 2).