Qualification of ELISA and PRNT methodologies to measure RSV humoral immunity using human clinical samples

Respiratory syncytial virus (RSV) represents a substantial public health burden worldwide, causing lower respiratory infections primarily in children under 5 and adults over 65. In recent years vaccines and monoclonal antibodies (mAbs) have demonstrated promising prophylaxis against RSV in vulnerable populations, benefitting individuals, families, and healthcare systems. However, this protection is incomplete, highlighting the importance of continued research and development towards novel and improved therapeutics. Clinically qualified endpoint assays are a crucial tool in these efforts, giving researchers insight into the magnitude, composition, and neutralization efficacies of the humoral immune response to RSV antigens. Here we describe the methodologies and clinical qualification of two correlated RSV assays, an Enzyme Linked Immunosorbent Assay (ELISA) and a Plaque Reduction Neutralization Test (PRNT). We demonstrate each assay is precise, linear, and translational. Publicly available controls increase reproducibility and transferability to other laboratories.