Insulin autoantibodies in the pre-diabetic period: correlation with islet cell antibodies and development of diabetes.
IgG and IgM class insulin autoantibodies were measured by an enzyme-linked immunosorbent assay in sera from members of the Barts-Windsor-Middlesex prospective family study for Type 1 (insulin-dependent) diabetes. One hundred and twelve individuals from 28 families were selected for study on the basis of a clearly defined islet cell antibody status. IgG insulin autoantibodies were found to be significantly associated with islet cell antibody positive (n = 30) versus islet cell antibody negative (n = 57) first degree family relatives (p = 0.002), with increased significance (p = 0.0003) if complement-fixing (CF)-islet cell antibody individuals (n = 20) only were considered. In addition, a significant association of IgG insulin autoantibodies with subsequent development of diabetes was observed within the CF-islet cell antibody positive group (p less than 0.0003). No such associations were found for IgM insulin autoantibodies, but a higher prevalence of these autoantibodies was observed in islet cell antibody negative first degree relatives (n = 57) compared with a control group of 73 Blood Bank donors (p = 0.00007), and they were significantly associated with siblings (n = 48) rather than parents (n = 39), (p = 0.001). We conclude that the presence of IgG insulin autoantibodies and CF-islet cell antibodies confer more risk for future development of diabetes than the presence of either marker alone.
D001323:Autoantibodies / Q000032:analysis*; D003920:Diabetes Mellitus / Q000235:genetics / Q000276:immunology / Q000503:physiopathology*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007330:Insulin Antibodies / Q000032:analysis*; D007515:Islets of Langerhans / Q000276:immunology*; D011236:Prediabetic State / Q000276:immunology*; D012016:Reference Values
D001323:Autoantibodies; D007074:Immunoglobulin G; D007330:Insulin Antibodies; C024211:islet cell antibody