Altered levels of cytokine, T- and B-lymphocytes, and PD-1 expression rates in drug- naïve schizophrenia patients with acute phase

Background: Altered immune function in patients with schizophrenia has been of great interest, and although many studies have explored the changes in peripheral immune cell levels in patients with acute-phase, relatively few studies have addressed the functional phenotype of immune cells and expression rates of programmed cell death protein 1 (PD-1)/ programmed cell death-Ligand 1 (PD-L1). The aim of this study was to investigate the extent of immune cells activation, PD-1/PD-1 expressions, and altered cytokine levels in drug-naïve schizophrenia patients with acute-phase. Methods Drug-naïve schizophrenia patients in acute-phase and healthy individuals were enrolled in this study as experimental and control groups, separately. Socio-demographic information including gender, age, duration of illness, and smoking status was collected for each subject. The percentage of T-, B-, and natural killer (NK)-cells, as well as their expressions of PD-1/PD-L1, and the levels of cytokines including interferon (IFN)-γ, tumor necrosis factor (TNF)-α, Interleukin (IL)-2, IL-4, IL-6, and IL-10, were examined. Results Drug-naïve schizophrenia patients in acute-phase had higher levels of peripheral blood CD4 + T cells and B cells, higher PD-1 expression in B cells, and lower levels of CD8 + T cells. In addition, IL-6 levels of peripheral blood were higher in schizophrenia patients (all P < 0.05). Conclusions Significant immune stress was present in schizophrenia patients with acute-phase.