The effect of T cell independent and cross-reactive antigen on the immune response to pneumococcal conjugate vaccination

B cell mediated priming following pneumococcal colonization

“…In conclusion, our previous findings demonstrated the benefit of pneumococcal colonization prior to vaccination [13]. The results presented here support our previous work and indicate that this effect is due to the generation of PPS-specific memory B cells found in the spleen.…”

“…These results indicate that colonization must stimulate the production of classswitched B cells and the activation of CD4 + helper T cells capable of producing specific IgG. The production of anti-PPS IgG antibody following pneumococcal colonization in mice has been demonstrated previously and confirmed in our model [13]. Moreover, work by Malley et al and van Rossum et al has shown that murine colonization stimulates the production of CD4 + T cells [23,5].…”

“…A majority of individuals have been colonized by the pneumococcus, which correlates with the significant levels of anti-PPS specific antibody in adults [6,3,7]. Previously, we have demonstrated that streptococcal colonization can have a significant effect on subsequent pneumococcal vaccination [13]. Nasopharyngeal colonization with S. pneumoniae, in particular serotypes 14, 19A, and 19F, primes the immune response so that the magnitude of the antibody response is increased following vaccination with CPV.…”

“…Previously we demonstrated that colonization by S. pneumoniae, or cross-reactive organisms such as Group B Streptococcus type III, primes the immune response to subsequent CPV immunization [13]. Mice previously colonized with live S. pneumoniae serotype 14 (sp14) demonstrated significantly greater IgG responses to CPV vaccination compared to mice primed with phosphate-buffered saline (PBS).…”