Successful capture of Toxocara canis larva antigens from human serum samples
Por:
Rodríguez-Caballero A., Martínez-Gordillo M.N., Medina-Flores Y., Medina-Escutia M.E., Meza-Lucas A., Correa D., Caballero-Salazar S., Ponce-Macotela M.
Publicada:
1 ene 2015
Resumen:
Background: Toxocara canis is a nematode that parasitizes dogs, while humans are paratenic hosts. When humans are infected the migrating larvae damage the liver, lungs and even the nervous system. Larva migrans diagnosis is based on immunological techniques; however, the commercial immunodiagnostic kits detect anti-T. canis antibodies which may cross-react with other parasites, mainly nematodes with extra-intestinal migration. Moreover, antibodies do not necessarily reflect an active infection; so detection and quantification of circulating antigens may provide appropriate and timely information for treatment, which prevents irreversible damage. Here we report the standardization of a monoclonal antibody based antigen capture ELISA to diagnose human toxocariasis without cross-reaction. Methods: We developed anti-T. canis polyclonal antibodies in rabbits and a monoclonal antibody in mouse which did not cross-react with 15 antigens from several parasites. The sandwich ELISA standardization was performed using sera from mice experimentally infected. We tested the method using 29 positive and 58 negative human sera previously typified with a commercial kit, which detects antibodies. Results: Only 5.0 µg/mL and 10 µg/mL polyclonal antibodies and monoclonal antibody, respectively, were needed in the sandwich ELISA standardization, detecting since 440 pg/mL larva antigens. Nine out of 29 antibody-positive sera were also positive for antigens and no false positive were found. Taking the antibody kit as the reference standard, the sensibility and specificity of the antigen test were 31% and 100%, respectively. Conclusions: With these tools we established a detection threshold as low as 440 pg/mL antigen. Monoclonal antibody is specific, and did not cross-react with antigens from other parasites. Detection of circulating antigens helps provide appropriate and timely treatment and prevents irreversible damage. © 2015 Rodríguez-Caballero et al.; licensee BioMed Central.
Filiaciones:
Rodríguez-Caballero A.:
Laboratorio de Parasitología Experimental, Instituto Nacional de Pediatría, Insurgentes Sur No. 3700-C, Colonia Insurgentes Cuicuilco, Delegación Coyoacan, México D.F, 04530, Mexico
Martínez-Gordillo M.N.:
Laboratorio de Parasitología Experimental, Instituto Nacional de Pediatría, Insurgentes Sur No. 3700-C, Colonia Insurgentes Cuicuilco, Delegación Coyoacan, México D.F, 04530, Mexico
Medina-Flores Y.:
Laboratorio de Anticuerpos Monoclonales, Instituto de Diagnóstico y Referencia Epidemiológicos, Calle Francisco P Miranda No. 177. Col., Delegacio
Medina-Escutia M.E.:
Laboratorio de Anticuerpos Monoclonales, Instituto de Diagnóstico y Referencia Epidemiológicos, Calle Francisco P Miranda No. 177. Col., Delegacio
Meza-Lucas A.:
n Alvaro Obregon, Mexico D.F, 01480, Mexico
Laboratorio de Pruebas Rápidas, Instituto de Diagnóstico y Referencia Epidemiológicos, Calle Francisco P Miranda No. 177. Col., Delegacion Alvaro Obregon, Mexico D.F, 01480, Mexico
Correa D.:
Laboratorio de Inmunología Experimental, Instituto Nacional de Pediatría, Insurgentes Sur No. 3700-C, Colonia Insurgentes Cuicuilco, Delegación Coyoacan, México D.F, 04530, Mexico
Caballero-Salazar S.:
Laboratorio de Parasitología Experimental, Instituto Nacional de Pediatría, Insurgentes Sur No. 3700-C, Colonia Insurgentes Cuicuilco, Delegación Coyoacan, México D.F, 04530, Mexico
Ponce-Macotela M.:
Laboratorio de Parasitología Experimental, Instituto Nacional de Pediatría, Insurgentes Sur No. 3700-C, Colonia Insurgentes Cuicuilco, Delegación Coyoacan, México D.F, 04530, Mexico
All Open Access, Gold
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