Tetravalent meningococcal polysaccharide vaccine is immunogenic in adult allogeneic BMT recipients

Forty-four adult BMT recipients transplanted from an HLA-identical sibling donor were randomized to receive meningococcal polysaccharide (Men PS) vaccine either 8 (early group; 22 patients) or 20 (late group; 22 patients) months after BMT. The geometric mean concentrations (GMC) of antibodies to serogroup A Neisseria meningitidis (Men A) and serogroup C Neisseria meningitidis (Men C), determined by an EIA method, decreased during the first 6 months after BMT but remained at a stable level thereafter. Before vaccination the GMCs of anti-Men A were 1.53 mug/ml and 1.61 mug/ml, but 1 month after vaccination they were significantly higher, 3.46 mug/ml and 6.39 mug/ml, in the early and late groups. The GMCs of anti-Men C increased from 0.37 mug/ml and 0.44 mug/ml before vaccination to 3.31 mug/ml and 4.62 mug/ml at 1 month after vaccination in the early and late groups, respectively. By 6 months after vaccination the GMCs of Men antibodies had decreased to levels of about 50% of those measured at I month after vaccination. Two-fold responses to Men A PS were seen in 52% and 74% and to Men C PS in 76% and 89% of the BMT recipients in the early and late groups, respectively. Chronic GVHD had no influence on the vaccination response. In the present study, Men PS vaccine induced good and equal antibody responses to Men A and Men C PSs in allogeneic BMT recipients regardless of timing after BMT, Vaccination against Neisseria meningitidis should be considered, especially in the event of travelling or military service greater than or equal to8 months after BMT.