Optimization and evaluation of an influenza A (H5) pseudotyped lentiviral particle-based serological assay

BackgroundNovel serological methods provide alternative options for sero-diagnosis, sero-epidemiology and for determining evidence of naturally acquired or vaccine induced immunity. Micro-neutralization tests are currently the gold standard for serological studies of highly pathogenic avian influenza in mammalian species but require handling live virus in a biosafety level (BSL) 3 environment. We previously reported the use of H5 pseudotyped lentiviral particles (H5pp) as an alternative to micro-neutralization tests in a BSL-2 setting (Nefkens et al., 2007).ObjectiveTo optimize and evaluate this newly developed H5pp assay on relevant clinical specimens.Study designWe optimise and evaluate the performance of the H5pp assay using well-characterized sera from humans with confirmed H5N1 disease or controls.ResultsThe H5pp assay is a reliable serological method for the detection and quantification of neutralizing antibody to H5-viruses.ConclusionH5pp provide a reliable and safe alternative for sero-diagnosis and sero-epidemiology of H5N1 infections in a BSL-2 setting.