title: Bovine IgG subclasses and fertility of Echinococcus granulosus hydatid cysts.
abstract: Hydatidosis is an important zoonotic disease of worldwide distribution, causing important health problems to humans and major economical losses in infected livestock. Echinococcus granulosus, the etiological agent of hydatid disease, induces a humoral immune response in the intermediate host (human and herbivorous) against hydatid cyst antigens. Specifically, IgGs are found in the laminar and germinal layers and inside the lumen of fertile and infertile hydatid cysts. In the germinal layer of infertile cysts IgGs are found in an order of magnitude greater than in the germinal layer of fertile cysts; a fraction of those IgGs are associated with high affinity to germinal layer proteins, suggesting their binding to specific parasite antigens. We have previously shown that those immunoglobulins, bound with high affinity to the germinal layer of hydatid cysts, induce apoptosis leading to cyst infertility. In the present work the presence of IgG1 and IgG2 subclasses in the germinal layer of both fertile and infertile hydatid cysts is reported. IgG1 is the most relevant immunoglobulin subclass present in the germinal layer of infertile cysts and bound with high affinity to that parasite structure. Contrarily, though the IgG2 subclass was also found in the germinal and adventitial layers, those immunoglobulins show low affinity to parasite antigens. We propose that the binding of an IgG1 subclass to parasite antigens present in the germinal layer is involved in the mechanism of cyst infertility.
authors: Escuela de Medicina Veterinaria, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Santiago, Chile; Cambridge Infectious Diseases, Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK.
authors: Silke
authors: S
authors: Riesle
authors: Escuela de Medicina Veterinaria, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Santiago, Chile.
authors: María Pía
authors: MP
authors: García
authors: Escuela de Medicina Veterinaria, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Santiago, Chile.
authors: Christian
authors: C
authors: Hidalgo
authors: Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
authors: Norbel
authors: N
authors: Galanti
authors: Laboratorio de Vacunas Veterinarias, Departamento Ciencias Biológicas Animales, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago, Chile.
authors: Leonardo
authors: L
authors: Saenz
authors: Escuela de Medicina Veterinaria, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Santiago, Chile. Electronic address: rparedes@unab.cl.
authors: Rodolfo
authors: R
authors: Paredes
mesh_terms: D000818:Animals; D000909:Antibodies, Helminth / Q000145:classification*; D002417:Cattle; D002418:Cattle Diseases / Q000469:parasitology*; D004443:Echinococcosis / Q000469:parasitology / Q000662:veterinary*; D048209:Echinococcus granulosus / Q000276:immunology*; D007074:Immunoglobulin G / Q000097:blood* / Q000145:classification
chemical_list: D000909:Antibodies, Helminth; D007074:Immunoglobulin G
keywords: Cyst fertility; Echinococcus granulosus; IgG subclass