Presenter of 1 Presentation
O058 - THE DEVELOPMENT OF SEROTYPE-SPECIFIC MONOCLONAL ANTIBODIES TO SUPPORT VACCINES AND DIAGNOSTIC TESTS FOR PNEUMOCOCCAL DISEASE. (ID 760)
Abstract
Background
Streptococcus pneumoniae is a leading cause of pneumonia, the single biggest infectious killer of adults and children worldwide (pre-COVID-19), particularity in low- and middle-income countries. Lower cost vaccines and improved diagnostics can support disease management. We developed specific monoclonal antibodies targeting 29 common serotypes to support vaccine development and diagnostics and we developed a serotype-specific urine antigen detection (SSUAD) assay to detect the 29 pneumococcal polysaccharide (PnPS) antigens in urine.
Methods
Mice were immunized with serotype specific PnPS conjugates and hybridomas generated from splenic B-cell fusions. Optimal clones were selected by screening their antibodies on a multiplexed PnPS antigen array for sensitivity and specificity. The best candidates were printed in multiplex arrays and screened via checkerboard analysis to confirm their performance for capturing and detecting soluble PnPs. The optimal antibody pairs for each serotype were included in an immunoarray.
Results
We generated at least one clone for each of the PnPS serotypes selected. Checkboard analysis of antibodies enabled us to create a prototype multiplexed-immunoarray wherein each serotype could be detected. Initial performance demonstrated a limit of detection as low as 1pg/mL of PnPS and minimal to no cross-reactivity with other serotype PnPS, except for 6A/C and 15A/B. There was strong intra-and inter-assay precision at <10% and <20% CV respectively.
Conclusions
A subset of these antibodies (14) are commercially available now with the complete set on offer Q3 2022. The prototype SSUAD provides a high-performance multiplexed serotype-specific screen using a plate-based immunoassay protocol and equipment common in many laboratories.