Natural anti-insulin autoantibodies in cats: enzyme-linked immunosorbent assay for the determination of plasma anti-insulin IgG and its concentrations in domestic cats.
Anti-insulin immunoglobulin G (IgG) has been found in the sera of healthy cats. To determine the concentrations of these antibodies, an enzyme-linked immunosorbent assay (ELISA) for anti-insulin IgG was developed. ELISA maintained the linearity of a standard concentration line between 67.5 and 2160 ng/ml. The coefficients of variances (CVs) of intra-assays in two different plasma samples were 4.0% and 3.7%, respectively. The inter-assay CVs in two different plasma samples were 5.1% and 6.9%, respectively. The dilution curves of two samples were rectilinear. Anti-insulin IgG was detected in all 84 of the healthy cats that were tested. Plasma anti-insulin IgG concentrations ranged from 80 to 1578 μg/ml, with a median concentration of 221 μg/ml, and this value correlated positively with total plasma IgG concentrations (r=0.383, p<0.01). In an intravenous glucose tolerance test, plasma anti-insulin IgG concentrations did not alter, even with changes in plasma glucose and insulin concentrations. The ELISA that was developed was able to determine plasma anti-insulin IgG in domestic cats, and confirmed that all healthy cats had plasma anti-insulin IgG. Determining the plasma concentrations of anti-insulin IgG in cats with various pathological conditions might clarify the role of anti-insulin IgG.
Department of Veterinary Medicine, United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
Satoshi
S
Takashima
Naohito
N
Nishii
Tatsuyuki
T
Hachisu
Masaaki
M
Kojima
Megumi
M
Kigure-Hoshino
Shizuko
S
Ogawa
Takafumi
T
Suzuki
Atsushi
A
Iwasawa
Yasunori
Y
Ohba
Hitoshi
H
Kitagawa
D000818:Animals; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology; D001786:Blood Glucose / Q000032:analysis; D002415:Cats / Q000097:blood / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D005951:Glucose Tolerance Test / Q000662:veterinary; D007074:Immunoglobulin G / Q000097:blood* / Q000276:immunology; D007328:Insulin / Q000097:blood; D007330:Insulin Antibodies / Q000097:blood* / Q000276:immunology; D008297:Male
D001323:Autoantibodies; D001786:Blood Glucose; D007074:Immunoglobulin G; D007328:Insulin; D007330:Insulin Antibodies
Anti-insulin IgG; Domestic cat; ELISA