Evaluation of two enzyme-linked immunosorbent assays for serodiagnosis of Aleutian mink disease virus infection in mink

Abstract

BackgroundAleutian disease in mink is caused by infection with Aleutian mink disease virus (AMDV). In Sweden, the infection most commonly causes classical Aleutian disease in which the immune system fails to neutralize the virus and the infection becomes persistent. Diagnosis of AMDV infection is based on serological methods that detect virus-specific antibodies. Traditionally counterimmunoelectrophoresis (CIEP) has been the preferred method, but in order to enable automation interest has been paid to other antibody detecting systems. Recently, at least two different ELISA systems that detect antibodies to AMDV have been manufactured; one is based on an in vitro grown AMDV as antigen, and the other system is based on the AMDV capsid protein VP2 as antigen. The aim of this study was to evaluate the two ELISA systems for detection of antibodies to AMDV using CIEP as the gold standard.ResultsWhen employing the mean optical density of the samples from CIEP negative mink plus three standard deviations as cut-off value, the ELISA with the VP2 antigen had a sensitivity of 99.7% and a specificity of 98.3% compared to CIEP (n = 364). Analysis of samples with the AMDV-G antigen based ELISA employing an assay cut-off value based on the negative control samples, as suggested by the manufacturer, resulted in a sensitivity of 54.3% and a specificity of 93.2% with reference to CIEP as the gold standard (n = 359). When employing the mean optical density of the samples from CIEP negative mink plus three standard deviations as cut-off value, the AMDV-G ELISA had a sensitivity of 37.6% and a specificity of 98.3%.ConclusionsThe ELISA system based on VP2 antigen had high sensitivity and specificity, and was concluded to be an alternative to the CIEP as a diagnostic tool for AMDV antibodies. In contrast, the AMDV-G ELISA suffered from low sensitivity when compared to CIEP.

High molecular polymorphism of the hypervariable region in the VP2 gene of Aleutian mink disease virus

“…To diagnose Aleutian disease, the counter-immunoelectrophoresis (CIEP) method is routinely used, and more recently also ELISA assays aimed at detecting the presence of specific antibodies (Knuuttila et al, 2009a;Andersson and Wallgren, 2013;Dam-Tuxen et al, 2014). However, in the case of strains inducing non-persistent infections, the level of antibodies in infected animals is low and often cannot be detected by serological methods (Andersson and Wallgren, 2013).…”

“…However, in the case of strains inducing non-persistent infections, the level of antibodies in infected animals is low and often cannot be detected by serological methods (Andersson and Wallgren, 2013). Molecular methods are oriented at detection of viral genetic material, whereas serological methods are limited to antibodies.…”

Occurrence of Aleutian mink disease in selected national mink farms in light of serological and molecular investigations

“…Choroba aleucka norek (Aleutian Mink Desease -AMD) ma ogromny wpływ na zdrowotność norek na całym świecie oraz powoduje duże problemy w gospodarce rolnej państw, gdzie hodowla norek stanowi ważny dział tej gospodarki (4,10,21). AMD najczę-ściej przebiega bezobjawowo (314), choć w przebiegu zakażenia obserwowano zaburzenia rozrodu, zmiany w okrywie włosowej oraz zmniejszenia przyrostów masy ciała (7,29).…”

“…Zwalczanie AMD oparte jest głównie na wykorzystaniu immunoelektroforezy przeciwprą-dowej (CIEP), w której występuje zjawisko precypitacji zachodzące pomiędzy antygenem a obecnymi w surowicy przeciwciałami swoistymi dla AMDV (10,14). Kontynuowane są badania nad wdrożeniem udoskonalonych testów ELISA (4,20) oraz próby opracowania nowych, czulszych metod molekularnych (17,25,27). Wynikają one m.in.…”

Detection of Aleutian disease virus by loop-mediated isothermal amplification

“…However, this method is laborious to perform. Other serological diagnostic methods, including modified CIEP [1,2,8,19], rocket line immunoelectrophoresis [5], and enzyme-linked immunosorbent assays [6,9,12,13,20] have been reported. But these methods may show a slowdown in the process of disease diagnosis because preparation of the antigen used in these methods is both labor and time-consuming.…”