Higher mass meningococcal group C-tetanus toxoid vaccines conjugated with carbodiimide correlate with greater immunogenicity.

•A panel of MenC-TT conjugate vaccines was produced with different chain-lengths;•MenC conjugates with longer saccharide chains were more immunogenic in mouse study;•Stoichiometric modelling of glycoconjugates can elucidate higher order structures;•Larger sized conjugates stimulated higher level of splenocyte profileration;•Confocal microscopy can be used to image meningococcal C on splenocyte surface.