Use of inactive beta-D-galactosidase for elimination of interference by anti-beta-D-galactosidase antibodies in immune complex transfer enzyme immunoassay for anti-thyroglobulin IgG in serum using beta-D-galactosidase from Escherichia coli as label.
A novel enzyme immunoassay (immune complex transfer enzyme immunoassay) for anti-thyroglobulin IgG using beta-D-galactosidase from Escherichia coli as label was reported previously. This immunoassay was highly sensitive in demonstrating anti-thyroglobulin IgG not only in all patients with Graves' disease and chronic thyroiditis but also in a large proportion of healthy subjects. However, the detection of anti-thyroglobulin IgG at low levels in some serum samples was difficult, probably due to the presence of anti-beta-D-galactosidase antibodies. In the present study, the use of inactive beta-D-galactosidase was tested for elimination of interference by anti-beta-D-galactosidase antibodies. Preincubation of serum samples with excess of inactive beta-D-galactosidase resulted in sufficiently low backgrounds to detect low levels of anti-thyroglobulin IgG with little effect on the dose-response of anti-thyroglobulin IgG. As a result, it was revealed that anti-thyroglobulin IgG was present in almost all healthy subjects as well as all patients with Graves' disease and chronic thyroiditis.
Kohno
T
T
Department of Biochemistry, Medical College of Miyazaki, Japan.
Katsumaru
H
H
Nakamoto
H
H
Yasuda
T
T
Mitsukawa
T
T
Matsukura
S
S
Tsunetoshi
Y
Y
Ishikawa
E
E
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000936:Antigen-Antibody Complex; D001323:Autoantibodies / Q000276:immunology*; D004926:Escherichia coli / Q000201:enzymology; D005260:Female; D005696:Galactosidases / Q000097:blood; D006111:Graves Disease / Q000097:blood* / Q000201:enzymology / Q000276:immunology; D006801:Humans; D007124:Immunoenzyme Techniques; D007074:Immunoglobulin G / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D013966:Thyroiditis / Q000097:blood* / Q000201:enzymology / Q000276:immunology
D000936:Antigen-Antibody Complex; D001323:Autoantibodies; D007074:Immunoglobulin G; C006606:anti-thyroglobulin; D005696:Galactosidases