An Enzyme‐Linked Immunosorbent Assay (ELISA) for Detection of Marek's Disease Virus‐Specific Antibodies and its Application in an Experimental Vaccine Trial

Abstract

An enzyme-linked immunosorbent assay (ELISA) for the detection of Marek's disease virus (MDV)-specific antibodies was developed. Chicken embryo cells (CEC) or chicken kidney cells (CKC) were infected with MDV vaccine strain CVI988/Rispens, and infected-cell lysates were prepared at day 5 post-infection by freeze-thawing. Uninfected-cell lysates served as negative controls. Sera were used at a 1 : 100 dilution and were added in parallel to wells containing the infected and uninfected cell lysates. The optical densities at 492 nm (OD(492 nm)) were measured after detection of bound chicken antibodies with anti-chicken IgG peroxidase conjugate and colour reactions using o-phenylenediamine (OPD) as a substrate. The best results concerning the signal-to-noise ratio were obtained by using CKC cells rather than CEC for antigen preparation. The OD(492 nm) of plasma or serum samples with infected CKC was <0.02 when samples of unvaccinated and unchallenged maternal antibody-negative white leghorn chickens were tested. Sera and plasma samples of positive control birds exhibited OD(492 nm) of <0.01 when tested with uninfected CKC. The assay was used to monitor a trial that compared experimental BAC DNA vaccines and a commercial vaccine. Sustained seroconversion and antibody titers that were constantly rising until day 84 after vaccination (71 days after challenge) was observed only when chickens did not develop Marek's disease. In contrast, chickens developing the disease mounted marginal and short-lived antibody titers only. We conclude that the developed ELISA may be a valuable tool for the evaluation of the efficacy of MDV vaccination under experimental but possibly also under field conditions.

Virus Spread Pattern within Infected Chicken Farms using Regression Model: the 2003–2004 HPAI Epidemic in the Republic of Korea

“…However, in our study, layer chickens were more likely to succumb to the viral disease. Broiler chickens have strong IgM levels, which are important in the early humoral immunity response, whereas layer chickens possess a humoral IgG response and cellular immunity (Koenen et al., 2002; Zelnik et al., 2004). Possibly, as HPAI progresses very quickly in the infected host, the broiler immune system may be better suited to resist the viral infection and further research is needed to confirm the difference in disease spreading between two chicken species.…”

Imperfect Vaccination Can Enhance the Transmission of Highly Virulent Pathogens

“…Enzyme-linked immunosorbent assay (ELISA) was performed to measure maternally derived antibody against MDV in serum samples from hatched chicks [ 58 ]. Serum samples were tested in duplicate at 1:100 dilution on ELISA plates coated with MDV-infected or non-infected cell lysates.…”

Genome-wide association studies of immune, disease and production traits in indigenous chicken ecotypes

“…Antibody titres were based on serological analyses using an in-house enzyme-linked immunosorbent assay (ELISA) for Salmonella enterica serovar Gallinarum (SG) and Pasteurella multocida (PM), according to the protocol described by Beal et al [ 24 ]. An in-house ELISA based on the protocol of Zelnik et al [ 25 ] was used for MDV. Serological data for IBDV was obtained using a Flockscreen antibody ELISA kit (x-OvO, Dunfermline, UK).…”