IgG subclass profile of serum antibodies to Leishmania chagasi in naturally infected and vaccinated dogs

Tricia M. F. S. Oliveira, Tiago W. P. Mineo, Melina Bason, Michael J. Day, Rosangela Z. Machado

Research output: Contribution to journalArticle (Academic Journal)

12 Citations (Scopus)

Abstract

Leishmaniosis is a zoonotic disease that is caused by Leishmania chagasi and transmitted by sandflies. In Brazil, canine visceral leishmaniosis (CVL) is an emerging disease in urban areas and dogs are the main reservoir host. The aim of the present study was to analyze IgG seroconversion of dogs to L. chagasi and to determine whether there was dominance of any particular IgG subclasses in this immune response. Antibody detection was performed by ELISA with 120 sera from confirmed seropositive dogs (obtained from epidemiological surveys), 24 samples from naturally infected dogs with clinical signs of the disease, and 40 sera from animals immunized with a commercially available vaccine. Ninety percent of seropositive survey population samples had detectable levels of anti-Leishmania total IgG by ELISA, compared with 70% of samples from symptomatic animals and only 13% of samples from the immunized dogs. The serological response in each group displayed a distinct bias in IgG subclass usage as detected by application of a panel of monoclonal antibodies specific for canine IgG1-IgG4. The survey population, which comprised predominantly asymptomatic dogs, had a dominant IgG1 response, while symptomatic dogs had a mixed pattern of IgG subclass usage. In contrast, sera from vaccinated animals had high titres of IgG2 Leishmania antibody. These distinctive IgG subclass profiles may be related to the infection status of the dogs. Moreover, detection of antigen-specific IgG subclasses may provide a valuable diagnostic tool for predicting the clinical outcome of visceral leishmaniasis, as well as differentiating infected dogs from vaccinated animals. (C) 2009 Elsevier B.V. All rights reserved.

Original languageEnglish
Pages (from-to)16-22
Number of pages7
JournalVeterinary Parasitology
Volume162
Issue number1-2
DOIs
Publication statusPublished - 26 May 2009

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