The existence of the overwhelming postsplenectomy
infection syndrome in adults after traumatic
splenectomy is controversial. Due to the similarity of the porcine immune system to man we chose the pig to study subsets of peripheral mononuclear cells after
splenectomy and resistance to experimental
Pneumococcal infection after splenic surgery and specific immunization. Female miniature pigs were assigned to four operative groups:
sham operation,
splenectomy, splenic resection, and heterotopic splenic
autotransplantation. Hematologic and flow cytometric analysis of mononuclear cells and their subsets revealed a marked
leukocytosis following
splenectomy and
autotransplantation but no significant shift in monocyte and B-cell numbers. Response of leukocytes to
septicemia, bacterial elimination from peripheral blood, and mortality were not affected by
splenectomy or spleen-preserving operations. Mortality of splenectomized animals was 18%, compared to 42% in
sham-operated controls (difference not significant). Immunization protected animals from development of
leukopenia, and led to an enhanced bacterial elimination, and a significantly decreased mortality of 5%, compared to 48% in nonimmune animals. Thus our data do not show significant effects of
splenectomy on subsets of porcine mononuclear cells or on resistance to experimental Pneumococcal
septicemia.