[The effect of splenectomy in immature mice]

Overwhelming postsplenectomy infection in childhood has been investigated extensively, both clinically and experimentally. The immunological change after splenectomy in immature mice is reported in this paper. The studies were carried out in 3-week-old immature mice and in 10-week-old mature mice groups. The immunological change after splenectomy in immature mice were as follows. One week after splenectomy, cellular immunity decreased, so that the phagocytosis of macrophages and the function of granulocytes were decreased. Three weeks after splenectomy, cellular immunity and the function of granulocytes improved but the phagocytosis of macrophages was still at the low level. Cellular immunity, the function of granulocytes and the phagocytosis of macrophages were within normal range 5 weeks after splenectomy. Several previous reports have demonstrated a lower IgM concentration. Tuftsin deficiency and activity decreased in opsonization after splenectomy. We showed the more primitive responses than cellular immunity are also depressed in this paper, that is, splenectomy in immature mice resulted in decrease in the phagocytosis of macrophages and dysfunction of granulocytes.