[Effects of immunosuppressive chemotherapy on serum levels of IgG subclasses--analysis in children with acute lymphoblastic leukemia and in children with aplastic anemia and autoimmune diseases receiving corticosteroid hormone].

Serum levels of IgG subclasses were analysed in 15 children with acute lymphoblastic leukemia (ALL) receiving maintenance chemotherapy and 10 children with aplastic anemia and autoimmune diseases receiving prednisolone therapy longer than 2 months (Steroid group). The results were as follows. Serum levels of IgG1 in ALL were significantly (p less than 0.05) lower than age matched normal controls, while the IgG1 levels in the Steroid group were as high as in normal controls. Serum levels of IgG2 in ALL and the Steroid group were significantly (p less than 0.005, p less than 0.02) lower than in normal controls. Serum levels of IgG3 in ALL and the Steroid group were as high as in normal controls. Serum levels of IgG4 in ALL and the Steroid group were significantly (p less than 0.005, p less than 0.05) lower than in normal controls. IgG2 and IgG4 should be more susceptible to suppression by immunosuppressive chemotherapy than IgG1, and IgG3 would hardly suppressed by immunosuppressive chemotherapy.