Pneumococcal neuraminidases increase platelet killing by pneumolysin.

: Neuraminidases are key virulence factors of pneumococci and desialylate platelet glycoproteins, thereby unmasking PLY-binding sites. This enhances binding of PLY and pore formation showing that pneumococcal neuraminidases and PLY act in concert to kill platelets. However, human polyvalent IgG preparations are promising agents for therapeutic intervention during severe pneumococcal pneumonia.