Immune complex transfer enzyme immunoassay for anti-ovalbumin IgA in serum.
BACKGROUND
An immune complex transfer enzyme immunoassay for antiovalbumin immunoglobulin A (IgA) was developed.


METHODS
Serum-specific antibody was reacted simultaneously with 2,4-dinitrophenyl-bovine serum albumin-ovalbumin conjugate and ovalbumin-beta-D-galactosidase conjugate. The complex formed from the three components was trapped onto polystyrene balls coated with anti-2,4-dinitrophenyl group immunoglobulin G, eluted with epsilonN-2,4-dinitrophenyl-L-lysine and transferred to polystyrene balls coated with anti-human IgA alpha-chain. Bound beta-D-galactosidase activity was determined by fluorometry.


CONCLUSIONS
The detection limit of this method for the measurement of specific anti-ovalbumin IgA was 9 fmol/tube, which was 20-fold lower than that of the enzyme-linked immunosorbent assay (ELISA). Because serum interference with this method was lower than that with the ELISA, the detection limit of this method was 300-fold lower than that by the ELISA. Anti-ovalbumin IgA was detected in 100% of healthy subjects, which was confirmed by pre-incubation with an excess amount of ovalbumin.
Hirota
Kouichi
K
Division of Maternal and Child Health Science, National Institute of Health and Nutrition, 1-23-1 Toyama, Shinjuku, Tokyo 162-8636, Japan. khirota@nih.go.jp
Kamashima
Tomomi
T
Hashida
Seiichi
S
Totani
Masayuki
M
D019297:2,4-Dinitrophenol / Q000276:immunology; D000328:Adult; D000818:Animals; D000918:Antibody Specificity; D002417:Cattle; D004797:Enzyme-Linked Immunosorbent Assay; D005453:Fluorescence; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods*; D007070:Immunoglobulin A / Q000097:blood*; D008863:Microspheres; D008875:Middle Aged; D010047:Ovalbumin / Q000276:immunology*; D011137:Polystyrenes; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000276:immunology; D001616:beta-Galactosidase / Q000276:immunology
D007070:Immunoglobulin A; D011137:Polystyrenes; D012710:Serum Albumin, Bovine; D010047:Ovalbumin; D001616:beta-Galactosidase; D019297:2,4-Dinitrophenol