title: [Europium-labelled Staphylococcus aureus protein A as a reagent for determining specific antibodies].
abstract: In this work the conditions of labeling protein A with europium ions were studied and the conjugates obtained in this study were compared with traditional peroxidase conjugates currently used in immunochemistry. The conjugates of protein A with Eu3+ chelate were obtained with the use of cyclic dianhydride of diethylenetriaminepentaacetic acid (DADETPA). Conjugation methods with the use of DADETPA was shown to permit obtaining high-quality conjugates with europium chelates. Europium-labeled protein A ensured the sensitivity of the determination of adsorbed IgG at a level of 2 ng/ml and the dynamic analytical range within 3-1,000 ng/ml, which essentially exceeded similar characteristics of peroxidase conjugates with protein A. Europium-labeled protein A was used for the detection of antibodies to Francisella tularensis in the sera of humans immunized against tularemia. The sensitivity of this assay exceeded that of the enzyme immunoassay 10- to 40-fold. A conclusion was made on the possibility of using europium labelled protein A for the determination of specific antibodies to F.tularensis. This preparation may be useful in the determination of specific antibodies in low-immune sera.
authors.forename: T V
authors.initials: TV
authors.lastname: Guzaeva
authors.forename: A M
authors.initials: AM
authors.lastname: Komarov
authors.forename: S V
authors.initials: SV
authors.lastname: Iurov
authors.forename: S Iu
authors.initials: SIu
authors.lastname: Pchelintsev
authors.forename: A V
authors.initials: AV
authors.lastname: Chudinov
authors.forename: S S
authors.initials: SS
authors.lastname: Afanas'ev
authors.forename: V P
authors.initials: VP
authors.lastname: Zav'ialov
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D000918:Antibody Specificity; D002614:Chelating Agents; D005063:Europium; D005069:Evaluation Studies as Topic; D005604:Francisella tularensis / Q000276:immunology*; D006801:Humans; D007124:Immunoenzyme Techniques; D007075:Immunoglobulin M / Q000097:blood; D007202:Indicators and Reagents; D008297:Male; D004369:Pentetic Acid; D011994:Recombinant Proteins; D012680:Sensitivity and Specificity; D013205:Staphylococcal Protein A
chemical_list: D000907:Antibodies, Bacterial; D002614:Chelating Agents; D007075:Immunoglobulin M; D007202:Indicators and Reagents; D011994:Recombinant Proteins; D013205:Staphylococcal Protein A; D005063:Europium; D004369:Pentetic Acid
vernacular_title: Belok A Staphylococcus aureus, mechennyĭ evropiem, kak reagent dlia opredeleniia spetsificheskikh antitel.