Variation in dengue virus plaque reduction neutralization testing: systematic review and pooled analysis.

Area of Science:

• Virology
• Immunology
• Public Health

Background:

• The plaque reduction neutralization test (PRNT) is the gold standard for detecting immune responses to dengue virus (DENV).
• Variations in PRNT methodologies across laboratories hinder comparability, particularly for DENV vaccine development.
• The impact of differing PRNT techniques and virus strains on assay results requires further characterization.

Purpose of the Study:

• To identify factors contributing to heterogeneity in PRNT results.
• To compare variations in PRNT titers between different dengue virus strains within serotypes and across different studies.
• To assess the impact of laboratory-to-laboratory differences on PRNT assay comparability.

Main Methods:

• Systematic review and pooled analysis of published literature reporting individual-level PRNT titers.
• Hierarchical models were used to compare variations between strains and across articles.
• Analysis included data from vaccine trials and natural DENV exposure studies.

Main Results:

• PRNT titers varied substantially between different strains within a DENV serotype.
• Strain choice accounted for 8.04% of between-titer variation after adjustments.
• Differences between articles (inter-laboratory variation) accounted for 50.7% of between-titer variance.

Conclusions:

• Lack of standardized PRNT assays complicates unbiased inferences about vaccine-induced protection.
• Standardized reference reagents and proficiency testing are needed to improve PRNT comparability.
• Improved quality assurance in dengue PRNT is essential for reliable vaccine evaluation.