INTEC (Universidad Nacional del Litoral and CONICET), Güemes 3450, Santa Fe, Argentina.
Colloids Surf B Biointerfaces. 2013 Jan 1;101:384-91. doi: 10.1016/j.colsurfb.2012.07.018. Epub 2012 Jul 21.
The physical adsorption and the chemical coupling of recombinant proteins of Trypanosoma cruzi onto polystyrene and core-shell carboxylated particles were respectively investigated with the ultimate aim of producing latex-protein complexes to be used in an immunoagglutination assay able to detect the Chagas disease. To this effect, two single proteins (RP1 and RP5) and a multiepitope protein derived from three antigenic peptides (CP2) were evaluated, and sensitizations were carried out at different pHs. The maximum physical adsorption was produced at pHs close to the protein isoelectric point (i.e., pH 6 for RP5 and pH 5 for RP1 and CP2). High fractions of antigens were chemically bound to the carboxyl groups, and the highest surface density of linked protein was also observed at pHs close to the protein isoelectric point. The three latex-protein complexes obtained by covalent coupling at such pHs were tested with sera from a panel of 16 infected and 16 non-infected patients. In the immunoagglutination assays, the latex-CP2 complex produced the best discrimination between positive and negative sera.
本研究旨在制备乳胶-蛋白复合物，并将其用于免疫凝集检测，以诊断恰加斯病。为此，我们分别研究了克氏锥虫重组蛋白在聚苯乙烯和核壳羧基化颗粒上的物理吸附和化学偶联。我们评估了两种单一蛋白（RP1 和 RP5）和一种源自三个抗原肽的多表位蛋白（CP2），并在不同 pH 值下进行了敏化实验。在接近蛋白等电点的 pH 值（即 RP5 的 pH6 和 RP1 及 CP2 的 pH5）下，物理吸附达到最大值。大量抗原通过化学结合与羧基结合，并且在接近蛋白等电点的 pH 值下，也观察到最高的蛋白表面密度。在这些 pH 值下，通过共价偶联获得的三种乳胶-蛋白复合物与来自 16 名感染和 16 名非感染患者的血清进行了测试。在免疫凝集检测中，乳胶-CP2 复合物对阳性和阴性血清的区分效果最佳。
