Microparticle-enhanced nephelometric immunoassay of anti-thyroid peroxidase autoantibodies in thyroid disorders.
Crude thyroid peroxidase extracted from human thyroid microsomes was covalently bound onto polyacrylic and polyfunctional copolymerized microparticles. We observed agglutination of the thyroid peroxidase-microparticle conjugate with 13 monoclonal antibodies (mAbs) specific for epitopes on four different antigenic domains of human thyroid peroxidase (TPO; EC 1.11.1.7), after addition of anti-mouse immunoglobulins. We quantified agglutination by measuring with a specially designed nephelometer the light scattered by the conjugates. This allowed us to develop a microparticle-enhanced nephelometric immunoassay for human anti-TPO autoantibodies (aAbs) with defined epitopic specificity, based on the ability of aAbs to inhibit mAb-induced agglutination. Applied to patients with autoimmune thyroid diseases, this assay confirmed the polyclonality of anti-TPO aAbs and their preferential reactivity toward epitopes located on the A and B antigenic domains of the TPO molecule. The same specificities seem to be present in patients with Hashimoto thyroiditis or Graves disease.
Harchali
A A
AA
Immunology Laboratory, Faculty of Medicine, Vandoeuvre, France.
Montagne
P
P
Ruf
J
J
Cuillière
M L
ML
Bene
M C
MC
Faure
G
G
Duheille
J
J
D001323:Autoantibodies / Q000097:blood*; D000939:Epitopes / Q000276:immunology; D006111:Graves Disease / Q000276:immunology; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007453:Iodide Peroxidase / Q000276:immunology*; D008863:Microspheres; D009391:Nephelometry and Turbidimetry; D013959:Thyroid Diseases / Q000276:immunology*; D013967:Thyroiditis, Autoimmune / Q000276:immunology
D001323:Autoantibodies; D000939:Epitopes; C056626:thyroid microsomal antibodies; D007453:Iodide Peroxidase