Application of an Improved Enzyme-Linked Immunosorbent Assay Method for Serological Diagnosis of Canine Leishmaniasis

Abstract

Accurate diagnosis of canine leishmaniasis (CanL) is essential toward a more efficient control of this zoonosis, but it remains problematic due to the high incidence of asymptomatic infections. In this study, we present data on the development of enzyme-linked immunosorbent assay (ELISA)-based techniques for the detection of antibodies against the recombinant protein Leishmania infantum cytosolic tryparedoxin peroxidase (LicTXNPx) and a comparison of the results with those employing soluble Leishmania antigens from promastigote or amastigote forms and the homologue recombinant protein L. infantum mitochondrial TXNPx (LimTXNPx). Moreover, we offer an evaluation of the diagnostic potential of rK39 for CanL in the Portuguese canine population and propose an improvement to the existing ELISA-based serological techniques by combining the LicTXNPx and rK39 antigens as a Leishmania antigen mixture (LAM). The data demonstrated that ELISAs based on soluble promastigote or amastigote antigens had generally higher levels of sensitivity for detection of antibodies in symptomatic or asymptomatic dogs than for detection of those against isolated recombinant proteins. Nevertheless, the specificities were found to be similar for all target antigens used. Importantly, the LAM-ELISA methodology improved the overall sensitivity, maintaining a high overall level of specificity. In addition, it was demonstrated that the detection of anti-LAM IgG2 can increase the accuracy of the serological diagnosis. Overall, the obtained results showed that the strategy of combining two well-defined

Mapping B-Cell Epitopes for the Peroxidoxin of Leishmania (Viannia) braziliensis and Its Potential for the Clinical Diagnosis of Tegumentary and Visceral Leishmaniasis

“…Peroxidoxin belongs to a family of proteins called peroxiredoxins (PRXs), which play a vital role in detoxifying reactive oxygen species in the parasites—an activity that is particularly relevant for Leishmania [33], [34]. These factors classify PRXs of these organisms as important virulence factors [35], [36], and previous studies have confirmed the antigenicity against these proteins in the sera of human and dogs infected by other Leishmania species [30], [37], [38]. In confirmation of these studies, we showed here that TL patients produced high levels of antibody against PRXs during the active cutaneous and mucosal clinical forms of the disease.…”

Proteins Selected in Leishmania (Viannia) braziliensis by an Immunoproteomic Approach with Potential Serodiagnosis Applications for Tegumentary Leishmaniasis

“…The authors concluded that this gene, when evaluated by a reverse transcription-PCR (RT-PCR) technique, could be considered an effective marker for the diagnosis of the disease. In another study, Santarém et al showed that a combination between the tryparedoxin peroxidase and K39 proteins was able to improve the VL serodiagnosis (49). However, to the best of our knowledge, an ELISA employing tryparedoxin peroxidase has not been evaluated.…”

Identification of Proteins in Promastigote and Amastigote-like Leishmania Using an Immunoproteomic Approach

“…Nonetheless, detection of asymptomatic dogs may be critical to control epidemics and to avoid the spread of the disease among dogs, as well as between dog and human populations [4], [5], [79]. However, total and soluble Leishmania antigen-based ELISA fails to detect a great percentage of asymptomatic cases of the disease [13], [80].…”