Development of an indirect ELISA for the serodiagnosis of canine infection by Onchocerca lupi

Abstract

Onchocercalupi is a zoonotic filarioid parasite of dogs and cats with widespread distribution. A specific non-invasive diagnostic assay for the detection of O.lupi infections remains unavailable. This study aimed to assess the accuracy, specificity, and sensitivity of an ELISA test designed using nine peptides from two O.lupi proteins. Sera (n = 54) collected from O.lupi infected dogs from endemic areas (Portugal and USA), alongside sera from dogs positive for Dirofilariaimmitis, D.repens, Cercopithifilariabainae, and Acanthocheilonemareconditum (n = 53) from a non-endemic area for O.lupi, as well as from helminth-free dogs (n = 60), were tested. The checkerboard titration method was applied for the optimization of peptide concentrations and conjugate anti-dog dilutions. Sensitivity, specificity, and optimal cut-off values were calculated using ROC curve analysis. All peptides reacted against sera of O.lupi, with no correlation between optic density (OD) values and microfilariae (mfs) loads. Sensitivity and specificity values ranging from 85.45 to 100%, and 88.89% to 100%, respectively, were recorded for all peptides examined, with 100% specificity and sensitivity observed for peptides 40_3, 40_5, 130_3, 120_3 and 40_1, 130_5, respectively. The maximum cut-off value was observed for peptides 40_5 (0.765) and 40_3 (0.708). Testing of sera from dogs positive for other filarioids resulted in lower OD values (up to 1.565) for peptides 40_3 and 40_5 when compared with O.lupi (up to 2.929). The availability of this assay will be of value in epidemiological studies of canine O.lupi infection in both endemic and non-endemic areas, and in assessing the risk for zoonotic transmission.

Beyond Tradition: Exploring Cutting-Edge Approaches for Accurate Diagnosis of Human Filariasis

“…Therefore, the development of a non-invasive, rapid, specific, and sensitive tool for serodiagnosis of O. lupi infection is greatly needed, both for monitoring epidemiology and helping sick people and animals. Further research should concentrate on assessing the efficacy of the test in detecting O. lupi infection in cats and humans and improving this diagnostic method [ 192 ].…”

“…Integrates immunoblotting and mass spectrometry to identify novel peptides for diagnostic tests [191] ELISA Utilises linear peptides of the Ol-MJA and Ol-PAR proteins [192] Molecular qPCR Amplification of COX1 gene fragment [199,202] 5.4. Wuchereria bancrofti Among the three human parasites responsible for lymphatic filariasis, W. bancrofti is the most prevalent.…”