Plaque reduction neutralization test for measles antibodies: Description of a standardised laboratory method for use in immunogenicity studies of aerosol vaccination

Centre for Infections, Health Protection Agency, London NW9 5EQ, UK.
Vaccine (Impact Factor: 3.62). 01/2008; 26(1):59-66. DOI: 10.1016/j.vaccine.2007.10.046
Source: PubMed


Clinical trials of measles vaccination administered as aerosol are planned with the aim of obtaining licensure. Measles antibody levels will be measured using the plaque reduction neutralization test (PRNT) to assess antibody responses as a surrogate marker of efficacy.
A working group examined laboratory protocols for measles PRNT in use at three reference centres and agreed to a standardised procedure, which was subsequently validated.
Assay validation showed quantitative results varied approximately threefold both within and between assays. The lower limit of detection was approximately 20milliInternational Units/mL.
A standardised laboratory protocol for measles PRNT was established and validated for use in clinical trials of aerosolized measles vaccines.

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    • "Plaque reduction assay modified from (19) was used to analyze SFV neutralization. Twenty-four well tissue culture plates were seeded with 1.5 × 105 Vero cells/well and incubated overnight at 37°C in a humidified atmosphere with 5% CO2. "
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    ABSTRACT: Many currently available inactivated vaccines require "adjuvants" to maximize the protective immune responses generated against the antigens of interest. Recent studies in mice with gamma-irradiated influenza A virus (γ-FLU) have shown its superior efficacy compared to other forms of inactivated FLU vaccines and its ability to induce both potent interferon type-I (IFN-I) responses and the IFN-I-associated partial lymphocyte activation. Commonly, IFN-I responses induced by adjuvants, combined in vaccine preparations, have been shown to effectively enhance the immunogenicity of the antigens of interest. Therefore, we investigated the potential adjuvant activity of γ-FLU and the possible effect on antibody responses against co-administrated antigens, using gamma-irradiated Semliki Forest virus (γ-SFV) as the experimental vaccine in mice. Our data show that co-vaccination with γ-FLU and γ-SFV resulted in enhanced SFV-specific antibody responses in terms of increased titers by sixfold and greater neutralization efficacy, when compared to vaccination with γ-SFV alone. This study provides promising evidence related to the possible use of γ-FLU as an adjuvant to poorly immunogenic vaccines without compromising the vaccine efficacy of γ-FLU.
    Frontiers in Immunology 06/2014; 5:267. DOI:10.3389/fimmu.2014.00267
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    • "The serum was transferred to cryotubes and stored at −20 • C until testing for antibodies at the Laboratory of Viral Vaccines of the INSP. Measles antibodies were evaluated by the plaque reduction neutralization test (PRN) in Vero cells [26]. Antibodies against rubella and mumps were evaluated by immune-enzymatic assays with commercial kits [27] [28]. "
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    Vaccine 05/2014; 32(29). DOI:10.1016/j.vaccine.2014.04.031 · 3.62 Impact Factor
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    • "The titers of isolated virus were measured using CPE microtitration assays and were expressed as the 50% tissue culture infective dose (TCID50) per mL according to the Kärber formula [38]. "
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