Two types of autoantibodies to adrenal medullary cells in type 1 (insulin-dependent) diabetic patients: prevalence, properties and implications.
Complement-fixing adrenal medullary antibodies were examined in sera from 170 (114 Type 1 and 56 Type 2) diabetic patients and normal subjects by indirect immunofluorescence methods. Two types of antibodies were detected; one showed a homogeneous immunofluorescence pattern (homogeneous-type) and the other a spotty pattern (spotty-type) in the cytoplasm of adrenal medullary cells. Both antibodies were IgG class and adrenal medulla-specific. The prevalence of the homogeneous-type was significantly higher in Type 1 diabetic patients with disease duration under 1 year (36%) than in those with duration of 1 year or more (1.1%), in Type 2 diabetic patients (1.8%) or in normal subjects (0%; P less than 0.01). Conversely, the prevalence of the spotty-type was not significantly different among all subjects examined (3.6-4.5%). The epitope for the homogeneous-type is likely to be a glycoconjugate since binding of this antibody was abolished after periodate oxidation. The epitope for spotty-type antibody is considered to be a peptide since it was trypsin sensitive. Patients who were positive for the homogeneous-type were also positive for islet cell antibodies, although their antibody titers were not correlated. We conclude that (1) adrenal medullary antibodies are of homogeneous-type or spotty-type and the antigenic determinants of these antibodies are different, and (2) the prevalence of the homogeneous-type is significantly higher in newly diagnosed Type 1 diabetic patients and its presence is associated with that of islet cell antibodies.
Itoh
N
N
Second Department of Internal Medicine, Osaka University Medical School, Japan.
Hanafusa
T
T
Katsura
H
H
Yamamoto
K
K
Takeda
A
A
Kurahashi
A
A
Nabika
T
T
Miyazaki
A
A
Miyagawa
J
J
Kono
N
N
D000293:Adolescent; D000313:Adrenal Medulla / Q000276:immunology*; D000328:Adult; D000368:Aged; D000918:Antibody Specificity; D001323:Autoantibodies / Q000032:analysis* / Q000276:immunology; D002675:Child, Preschool; D003165:Complement System Proteins / Q000276:immunology; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology*; D003929:Diabetic Neuropathies / Q000276:immunology; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007223:Infant; D008297:Male; D008875:Middle Aged
D001323:Autoantibodies; D007074:Immunoglobulin G; C024211:islet cell antibody; C056626:thyroid microsomal antibodies; D003165:Complement System Proteins