H Kayhty

..An 11-valent pneumococcal conjugate vaccine could provide significantly larger reduction in pneumococcal disease burden than the currently available 7-valent vaccine formulation in many countries...

..Mucosal antibodies have been suggested to have a role in defence against pneumococcal infections. We investigated here the ability of a seven-valent pneumococcal conjugate vaccine, PncOMPC, to induce mucosal immune response...

..The protective efficacy of the conjugate vaccines against carriage, acute otitis media, and invasive infections is being studied...

..Owing to the general reduced virulence of the latter, this has only had a modest effect on disease, but the possibility of more virulent nonvaccine serotypes arising cannot be ignored and should be the focus of continued surveillance...

..However, data are still missing on the minimal protective immune response and serologic correlates or surrogates of protection...

..Mucosal antibodies were found rarely after the primary series but in a greater proportion after the booster. In conclusion, both vaccines were immunogenic...

..In conclusion, the immunization of infants with this 11-valent pneumococcal conjugate vaccine increased avidity of IgG, suggesting successful immunologic priming...

..Furthermore, the different structure of the two conjugate vaccines might affect the nature of the response. Thus a different vaccine may be optimal for induction of a mucosal response than is of systemic responses...

..Thus, avidity was probably not a limiting factor influencing OPA. The effect of IgG2/IgG1 ratio on OPA was mostly negative but insignificant...

..All age groups were capable of producing antibodies to the 3 proteins. The antibody concentrations increased with age and were strongly associated with pneumococcal exposure, whether by carriage or infection (acute otitis media)...

..In the latter group, however, the avidity of anti-6B was high before boosting...

..No vaccine specific differences were found in avidity of anti-14 or -19F antibodies. By contrast, antibody avidity to 6B and 23F differed significantly between the vaccine groups, PncCRM and PncT inducing antibodies of highest avidity...

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..Pneumococcal polysaccharide vaccines are not protective against the most common pneumococcal infections in infancy. The importance of pneumococcal diseases and emerging antimicrobial resistance emphasize the need for prophylaxis...

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..The previous vaccination had not induced long lasting IgA-mediated memory. IgA antibodies were secretory, and most of IgG was serum derived. The IgG salivary response seen was similar to the serum response...

..We believe that the mucosal immune response is potentially an important characteristic of the pneumococcal vaccines and should thus be measured when the new pneumococcal conjugate vaccines are evaluated...

..Antibodies induced by PncT, however, had a significantly altered IgG2/IgG1 ratio (P < 0.05), with a higher proportion of IgG1...

..Furthermore, the IgG2/IgG1 ratio did not affect the detection of IgG1, the isotype usually represented by a lower concentration...

..Although pneumococcal type 6B conjugate vaccines elicit antibodies that cross-react with type 6A, not all anti-6B antibodies are functionally cross-reactive...

..This was true in children 9-24 months old (odds ratio [OR], 0.49; 95% confidence interval [CI], 0.31-0.78) but not in children <9 months old (OR, 0.81; 95% CI, 0.48-1.35)...

..We suggest that nasopharyngeal IgA antibody to pneumolysin can be produced early in life by pneumococcal colonization...

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..The specificity of antibodies, especially in sera from nonimmunized subjects, measured by EIA can be questioned...

..Antibodies increased modestly, even in children without known contact with Streptococcus pneumoniae and in children with contact with heterologous serotypes. Antibody concentrations were equal after carriage or AOM...

..Since the sensitivities of the OPA assays differed, the most prominent discrepancies between the techniques were found at low antibody concentrations...

..The conjugate vaccine with adjuvant was associated with Th2 type of activation indicated by an enhanced IL-5 secretion in response to the tetanus and diphtheria protein antigens...

..Noteworthy, immunologic memory seems to be induced already by first doses during newborn period. These data suggest that protection against invasive Hib infections may be achieved early in life...

..Thus, the effect on the tetanus and diphtheria immunity of multivalent conjugate vaccines containing tetanus and diphtheria toxoids as carriers needs to be evaluated before such vaccines are routinely implemented...

..The possible impact of the IgA subclass distribution on protection of mucosal surfaces by natural or vaccine-induced antibodies needs to be determined...

..7,16a, variably against the P1.7,16b and P1.7,16c, but not against the P1.7,16d variant. Our findings therefore suggest that certain subtype variants may escape protection in vivo conferred by PorA specific antibodies...

..Especially patients whose donors have low-specific antibody concentrations may benefit from donor vaccination with protein and conjugate vaccines...

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