Spleen-Associated Effects on Immunity in Hepatitis B Virus-Related Cirrhosis with Portal Hypertension

Our study aimed to investigate the histologic and immunological changes of portal hypertension (PH) pre- and postsplenectomy in hepatitis B virus (HBV)-related cirrhosis. Peripheral blood samples were obtained from 30 patients with HBV-related cirrhosis and PH at pre- and postsplenectomy time points and from 15 healthy subjects. Spleen tissue specimens were collected from 15 of the patients with HBV-related cirrhosis and from 8 control patients who had undergone splenectomy due to trauma. Immunohistochemical staining was performed to evaluate the immune effector cells and the expression of negative immune regulators. Flow cytometry was used to investigate the immunophenotypes and percentages. The spleen of cirrhotic patients with PH showed extensive depletion of splenic CD4, CD8, and human leukocyte antigen DR cells along with overexpression of the inhibitory receptors programmed death-1 (PD-1) and T cell immunoglobulin domain and mucin domain-3 and their ligands (PD-L2 and galectin-9). Peripheral blood of patients with PH showed remarkable decrease in proportions of CD8 T cell and natural killer (NK) cells and increase in regulatory T (Treg) cells, as well as high expression of PD-1 in CD4/8 T cells. Compared with presplenectomy patients, cirrhotic patients with PH showed increased proportions of CD8 and NK cells, decreased proportion of Treg cells, and decreased expression of PD-1 in peripheral blood CD4/8 T cells after splenectomy. PH-spleen could lead to peripheral tolerance and immunosuppression in HBV cirrhotic patients, and splenectomy may cause beneficial immunological changes.