Spontaneous and Pokeweed Mitogen-Induced in vitro IgM Production in Children and Adolescents with Insulin-Dependent Diabetes mellitus

Abstract

Serum IgA, IgG and IgM levels, spontaneous and pokeweed mitogen (PWM)-induced in vitro IgM production (determined by ELISA) and blastogenic responses of peripheral mononuclear cells to PWM were evaluated in 4 insulin-dependent (IDDM) children, at the onset and after 4, 8, 12 months of disease, and in 32 children and adolescents with IDDM of 1–14 years duration (mean 4.8 ± 3.8 years). Fifteen age-matched healthy subjects served as controls. Serum immunoglobulin levels were normal in 31 (86%) patients. Spontaneous in vitro IgM production showed no significant difference between IDDM patients and controls. The PWM-stimulated lymphocytes from IDDM patients at onset or after 4 months of disease produced significantly lower concentrations of IgM compared to long-standing IDDM patients or to controls. No different blastogenic response to PWM was observed in IDDM patients compared to controls. No correlation was present between the immunological parameters evaluated and metabolic control. Our data suggest that a defect of antibody producing B lymphocytes or an alteration of T cell can occur during the early stages of diabetes.