Journal article

Capsular Serotyping of Streptococcus pneumoniae Using the Quellung Reaction

Maha Habib, Barbara D Porter, Catherine Satzke

Journal of Visualized Experiments | JOURNAL OF VISUALIZED EXPERIMENTS | Published : 2014


There are over 90 different capsular serotypes of Streptococcus pneumoniae (the pneumococcus). As well as being a tool for understanding pneumococcal epidemiology, capsular serotyping can provide useful information for vaccine efficacy and impact studies. The Quellung reaction is the gold standard method for pneumococcal capsular serotyping. The method involves testing a pneumococcal cell suspension with pooled and specific antisera directed against the capsular polysaccharide. The antigen-antibody reactions are observed microscopically. The protocol has three main steps: 1) preparation of a bacterial cell suspension, 2) mixing of cells and antisera on a glass slide, and 3) reading the Quell..

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Awarded by Bill and Melinda Gates Foundation (PneuCarriage project)

Funding Acknowledgements

This work was supported by the Bill and Melinda Gates Foundation (PneuCarriage project, Grant 52099) and the Victorian Government's Operational Infrastructure Support Program. Thanks to Eileen Dunne, Janet Strachan, and Kim Hare for critical reading of the manuscript.