Adjuvant Quil A improves protection in mice and enhances opsonic capacity of antisera induced by pneumococcal polysaccharide conjugate vaccines.

The adjuvant effect of Quil A on the primary antibody response of mice to pneumococcal capsular polysaccharide conjugates was examined. Quil A increased the anti-capsular polysaccharide antibody titres, the protection against Streptococcus pneumoniae, and the opsonic capacity of the antibodies as measured in a newly developed in vitro phagocytosis assay, using the mouse macrophage cell line J774.