IL6 and major depressive disorder: Increase in biomarker levels after treatment was significantly correlated with reduction in depression symptomatology for TNF-α (r = −0.22, p = 0.020), IL-6 (r = −0.23, p = 0.016), IL-10 (r = −0.23, p = 0.022) and CRP (r = −0.30, p < 0.001) (Table 2), where the negative signs indicate a correlation between biomarker increase and HAMD score reduction (week 10 vs. baseline).