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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    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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    • "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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