Differential diagnosis of PRV-infected versus vaccinated pigs using a novel EuNPs-virus antigen probe-based blocking fluorescent lateral flow immunoassay.

A novel time-resolved fluorescence blocking lateral flow immunoassay (TRF-BLFIA) was developed for on-site differential diagnosis of pseudorabies virus (PRV)-infected and vaccinated pigs using europium nanoparticles (EuNPs)-labeled virion antigens and high titer PRV gE monoclonal antibodies (PRV gE-mAb). Upon application of a positive serum sample, the specific epitopes of gE protein on the EuNPs-PRV probe were blocked, inhibiting binding to the PRV gE-mAb on the T line, resulting in low or negligible fluorescence signal, whereas when a negative sample was applied, EuNPs-PRV probes would be able to bind the antibody at the T line, leading to high fluorescence signal. Under optimized conditions, TRF-BLFIA provided excellent sensitivity and selectivity.

Immune-tolerizing procedure for preparation of monoclonal antibodies against glycoprotein E of Pseudorabies virus.

The glycoprotein E (gE) of pseudorabies virus (PRV) is known to be an important marker protein in the control and eradication of Aujeszky's disease. In this study, BALB/c mice were immunized with gE-deleted PRV as tolerogen and with wild-type PRV as immunogen. The spleen cells from the immunized mice were then fused with the myeloma cell line Sp2/0.

Development of a convenient immunochromatographic strip for the diagnosis of infection with Japanese encephalitis virus in swine.

Japanese encephalitis (JE) is caused by the Japanese encephalitis virus (JEV). It is a major public health problem in Asia. JEV infects swine which results in fatal encephalitis, abortion and stillbirth in pregnant sow, and hypospermia in boars.

Avian influenza (H5N1) virus in waterfowl and chickens, central China.

In 2004, 3 and 4 strains of avian influenza virus (subtype H5N1) were isolated from waterfowl and chickens, respectively, in central People's Republic of China. Viral replication and pathogenicity were evaluated in chickens, quails, pigeons, and mice. We analyzed the sequences of the hemagglutinin and neuraminidase genes of the isolates and found broad diversity among them.

A latex agglutination test for the rapid detection of avian influenza virus subtype H5N1 and its clinical application.

A rapid and simple latex agglutination test (LAT) for the detection of avian influenza virus (AIV) subtype H5N1 in chicken allantoic fluids, tracheal swabs, and tissues was developed. Monoclonal antibodies against the hemagglutinin glycoprotein of H5N1 were covalently coupled onto the surface of carboxylated latex bead using a water-soluble carbodiimide to obtain sensitized latex particles (SLP). These SLPs strongly agglutinated in the presence of allantoic fluid containing H5N1, but not fluids containing other AIV sub-types such as HIN1, H3N2, H4N6, and H9N2.

Different neutralization efficiency of neutralizing monoclonal antibodies against avian influenza H5N1 virus to virus strains from different hosts.

BALB/c mice were immunized with formalin-treated influenza A/CK/Hubei/327/2004 virus. Six monoclonal antibodies specific to HA were selected, designed 1H8, 1D11, 2B7, 2C9, 2H4 and 4C9, respectively. The six Mabs probed linear epitopes by western blot assays.

[Preparation and partial characterization of monoclonal antibodies specific for nuclear protein of avian influenza virus].

Aim: To prepare the monoclonal antibodies (mAbs) specific for nuclear protein (NP) of avian influenza virus (AIV) and identify their biological properties.

Methods: BALB/c mice were immunized with AIV (formaldehyde-inactivated AIV H9N2, Triton X-100-lysed H9N2 and AIV NP expressed in E.coli, respectively).

Generation of monoclonal antibodies and epitope mapping of ApxIVA of Actinobacillus pleuropneumoniae.

To study functions of ApxIV, a species-specific and in vivo inducible RTX toxin identified in Actinobacillus pleuropneumoniae recently, and to develop a diagnostic trial distinguishing the pigs infected naturally and vaccinated with inactivated and/or subunit vaccines, we attempted to prepare monoclonal antibodies against ApxIV. BALB/c mice were immunized with ApxIVAN and ApxIVAC which are N- and C-terminal halvies (814 and 997 amino acids, respectively) of ApxIVA produced in E. coli BL21 (DE3), respectively.