Eu3+-labeled Staphylococcus aureus protein as reagent for the determination of specific antibodies

• Published in: Zhurnal mikrobiologii, ehpidemiologii i immunobiologii (Russian Federation) no. 4
• Main Authors: Guzaeva, T.V, Komarov, A.M, Yurov, S.V, Pchelintsev, S.Yu, Chudinov, A.V, Afanas'ev, S.S, Zav'yalov, V.P
• Format: Publication
• Language: Russian
• Published: 1994
• Subjects: ENFERMEDADES DE LOS ANIMALES; ENFERMEDADES HUMANAS; ENFERMEDADES INFECCIOSAS; IMMUNODIAGNOSTIC; INMUNODIAGNOSTICO; MALADIE DE L'HOMME; MALADIE DES ANIMAUX; MALADIE INFECTIEUSE; PROTEINAS UNICELULARES; PROTEINE MICROBIOLOGIQUE; REPONSE IMMUNITAIRE; RESPUESTA INMUNOLOGICA; STAPHYLOCOCCUS AUREUS

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 (DADETRA). Conjugation methods with the use of DADETRA were 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