CD19 and major depressive disorder: The final analysis revealed four independent predictors that were strongly associated with the diagnosis of BD and MDD, including CD19+ B cell counts (OR, 1.109; 95% CI, 1.068–1.152), CD3+ T cell counts (OR, 1.107; 95% CI, 1.065–1.150), CD3–CD16/56+ NK cell counts (OR, 1.120; 95% CI, 1.074–1.168), total lymphocyte counts (OR, 0.904; 95% CI, 0.871–0.939), and shown in a forest plot (Supplementary Figure 2).