Vaccines based on recombinant protein antigens often require immunostimulants. Both nanoparticles and chitosan and its derivatives can enhance immunogenicity. For this reason, in the presented studies, PLGA nanoparticles were functionalized with different chitosan derivatives and optimized as effect enhancers for the pneumococcal protein antigen PspA4Pro.

Chitosan shows great potential as part of drug release systems of orally administered drug formulations. Another interesting use is as an antigen platform for vaccines. We present an article in which pneumococcal membrane protein-loaded chitosan capsules were prepared and evaluated for their efficacy for a nasally administered vaccine.