Development of an immunochromatographic strip test for antigen detection of elephant endotheliotropic herpesvirus in Asian elephants (Elephas maximus)

• Published in: Journal of virological methods Vol. 311; p. 114627
• Main Authors: Guntawang, Thunyamas, Sittisak, Tidaratt, Srivorakul, Saralee, Photichai, Kornravee, Aiumurai, Pisinee, Thitaram, Chatchote, Sthitmatee, Nattawooti, Hsu, Wei-Li, Sookrung, Nitat, Pringproa, Kidsadagon
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2023
• Subjects: Animals; antigen detection; Antigens, Viral; blood; detection limit; DNA polymerase; DNA-directed DNA polymerase; EEHV; EEHV-hemorrhagic disease; Elephantid betaherpesvirus 1; Elephants; Elephas maximus; Escherichia coli; etiological agents; goats; gold; Gold Colloid; Herpesviridae - genetics; Herpesviridae Infections - diagnosis; Herpesviridae Infections - veterinary; immunoaffinity chromatography; Immunochromatographic strip test; infrastructure; Rabbits; rapid methods; viral genome; virulence; EEHV-hemorrhagic disease; DNA polymerase; EEHV; Immunochromatographic strip test
• ISSN: 0166-0934; 1879-0984; 1879-0984
• DOI: 10.1016/j.jviromet.2022.114627

Elephant endotheliotropic herpesvirus (EEHV) is the causative agent of EEHV-hemorrhagic disease (EEHV-HD) in elephants worldwide. This disease is highly virulent and a predominant cause of fatalities in young Asian elephants. Rapid diagnosis and aggressive therapies have been determined to be a key strategy in the successful treatment of this disease. Herein, we have developed the immunochromatographic strip test for EEHV detection. Accordingly, 31.2 kDa of partial EEHV DNA polymerase (DNApol) protein was expressed in Escherichia coli and used to generate rabbit polyclonal anti-EEHV DNApol antibodies. These were then used to develop an ICS test for EEHV antigen detection using the double-antibody sandwich colloidal gold method. Anti-EEHV DNApol antibodies conjugated with 40 nm colloidal gold solution were used as a detector, while rabbit anti-EEHV DNApol and goat anti-rabbit IgG antibodies immobilized on the nitrocellulose membrane were used as the test and control lines, respectively. The test had a detection limit of 1.25 × 105 viral genome copies (vgc)/mL of EEHV obtained from blood samples. Moreover, no specialized equipment or laboratory infrastructure was required in the administration of this test. This developed ICS test for EEHV antigen detection can be used in field application for the rapid detection of EEHV in resource-limited environments. •A novel immunochromatographic strip (ICS) test for rapid EEHV antigen detection in Asian elephants was developed in the present study.•Anti-EEHV DNApol antibodies conjugated with colloidal gold solution were used as a detector, while rabbit anti-EEHV DNApol was used at the test line.•This newly developed test had a limit of detection (LOD) value of EEHV in the whole blood samples of 125,000 vgc/mL and could be applied to saliva sample.•No special laboratory equipment required in the administration of this test.