Amaral J A, Tino De Franco M, Carneiro-Sampaio M M S, Carbonare S B
Laboratório de Imunogenética, Instituto Butantan, São Paulo, Brazil.
Res Vet Sci. 2002 Jun;72(3):229-34. doi: 10.1053/rvsc.2002.0551.
IgY, the egg yolk immunoglobulin, equivalent to the IgG from mammals, has been used in veterinary practice for passive immunisation against bacterial or viral infectious diseases. Enteropathogenic Escherichia coli (EPEC) is the main etiological agent of infantile diarrhoea in Brazil and other developing countries. Our aims were to isolate immunoglobulin IgY from egg yolk laid by EPEC -immunised Leghorn chickens and to study its reactivity to the antigens from this pathogen, including some virulence factors. Leghorn chickens were immunised with a bacterial suspension intramuscularly (three hens) or intravenously (three hens) or with PBS (two hens). Eggs were collected over a period of 17 weeks. IgY isolation procedures were carried out by salt precipitation (ammonium sulphate, in solid form) followed by centrifugations and dialysis. Final preparations were submitted to sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS - PAGE), enzyme-linked immunosorbent assay (ELISA) and immunoblotting. All immunised animals developed good levels of antibodies reactive to whole bacteria or lipopolysaccharide (LPS), in contrast to the control ones. Immunoblottings allowed the recognition of several antigenic fractions of bacterial antigens, some of which had a molecular weight compatible with bacterial virulence factors, confirming the efficacy of the immunisation and the adequacy of the method.
卵黄免疫球蛋白（IgY）等同于哺乳动物的IgG，已被用于兽医实践中，用于被动免疫以抵抗细菌或病毒感染性疾病。肠致病性大肠杆菌（EPEC）是巴西和其他发展中国家婴幼儿腹泻的主要病原体。我们的目标是从经EPEC免疫的来亨鸡所产蛋的蛋黄中分离免疫球蛋白IgY，并研究其与该病原体抗原（包括一些毒力因子）的反应性。将来亨鸡分别通过肌肉注射（三只母鸡）或静脉注射（三只母鸡）细菌悬液或注射PBS（两只母鸡）进行免疫。在17周的时间内收集鸡蛋。通过盐沉淀法（固体硫酸铵），然后进行离心和透析来进行IgY分离程序。最终制剂进行十二烷基硫酸钠聚丙烯酰胺凝胶电泳（SDS - PAGE）、酶联免疫吸附测定（ELISA）和免疫印迹分析。与对照动物相比，所有免疫动物都产生了对全菌或脂多糖（LPS）有反应的高水平抗体。免疫印迹分析能够识别细菌抗原的几个抗原部分，其中一些的分子量与细菌毒力因子相符，证实了免疫的有效性和方法的适用性。
