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. This evidence concerns the gene PDCD1 and schizophrenia.