According to researchers at the Max Planck Institute for Colloids and Interfaces, a molecule consisting of three adjoined sugars is sufficient to protect against infections with highly virulent and antibiotic-resistant streptococci.

The trimer stimulates the immune system to form antibodies against the bacterium Streptococcus pneumoniae of serotype 8, short ST8.

In order to find out which part of the capsular saccharide induces effective antibodies, the researchers analyzed the binding behavior of the antibodies more precisely. They ultimately showed that a triple sugar containing two glucose and one galactose molecule mediates the protective immune response.

Addition of the synthetic sugar molecule to the current pneumococcal vaccine Prevnar 13, expanded the protection in vaccinated animals from 13 to 14 serotypes including the dangerous ST8 pathogen.