Correlation between human innate and adaptive immune responses to T-cell independent or dependent meningococcal vaccines.

Thirty healthy adults (18-45 years of age) with no history of prior meningococcal vaccination and no contraindications to immunization will be vaccinated using either the meningococcal conjugate vaccine (MCV) or the meningococcal non-conjugate polysaccharide vaccine (MPSV). The study will be conducted as a randomized double blinded trial. Vaccine administration will be performed by an unblinded vaccine administrator, who will not be involved in subsequent assessments. Blood samples will be collected on Days D0 (at enrollment) and D3, D7, D14, D30 and D180 post vaccination to study innate and adaptive immunity markers. Even though meningococcal vaccination is considered safe, volunteers are asked to report any local or systemic AEs for 30 days post vaccination and any SAEs for 180 days post vaccination.