CD4 and schizophrenia: The main findings of this study were as follows: (1) patients with schizophrenia had higher levels of peripheral blood B lymphocytes and CD4+ T lymphocytes, higher PD-1 expression of B lymphocytes, and lower levels of CD8+ T lymphocytes; (2) the level of IL-6 in peripheral blood was higher in patients with acute schizophrenia, but the results were no longer significant after adjusting for confounding factors such as gender, age and smoking.