The relationship between partial splenectomy and peripheral leukocyte count

Partial splenectomy is accepted as a treatment modality for hypersplenism permitting preservation of the spleen functions. Since a prominent leukocytosis is a marked event after total splenectomy, it was the aim of the present study to compare the peripheral white blood cell counts (PWBC) and immune response in mice following partial and total splenectomy. Four groups of animals were included in the study: mice in which 70% of the spleen was removed, animals that underwent total splenectomy, mice with sham operation, and a group of mice that served as controls. The proliferative response of peripheral blood mononuclear cells, peritoneal cells, and splenocytes was examined using concavalin (Con) A. In distinction from marked leukocytosis observed in mice after total splenectomy, in partially splenectomized mice the PWBC counts did not show any significant increase during a follow-up period of up to 2 months after surgery. The mitogen response of the mononuclear cells to Con A in partially splenectomized mice was similar to that of controls, while in animals after total splenectomy, it was increased in cells from the peripheral blood and decreased in those from the peritoneum. The results indicate that removal of as much as about 70% of the spleen in mice is sufficient to maintain a normal PWBC count, suggesting a regulatory role of the spleen remnant on the PWBC production. The normal mitogen response of the cells to Con A indicates that the spleen rudiment preserves at least a part of the immune activity of the intact spleen.