Does vaccination with 4CMenB convey protection against meningococcal serogroup B strains not predicted to be covered by MATS? A study of the UK clonal complex cc269

• Main Authors: Maria Stella (Author), Maria Giuliani (Author), Alessia Biolchi (Author), Sara Tomei (Author), Rosita De Paola (Author), Xilian Bai (Author), Ray Borrow (Author), Jay Lucidarme (Author), Rita La Gaetana (Author), Daniela Toneatto (Author), Mariagrazia Pizza (Author), Laura Serino (Author), Elena Mori (Author), Marzia Monica Giuliani (Author)
• Format: Book
• Published: Taylor & Francis Group, 2020-04-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

The Meningococcal Antigen Typing System (MATS) has been developed as an hSBA surrogate to evaluate potential coverage afforded by the 4-component meningococcal serogroup B vaccine (4CMenB: Bexsero, GSK). We investigated whether the lower value of MATS coverage among invasive Meningococcus serogroup B clonal complex 269 strains from the United Kingdom (53% in 2014-2015 versus 73% in 2007-2008) reflected the lower bactericidal activity of the vaccine against these isolates. A total of 34 MATS-negative strains (31 were cc269 or closely related) were tested against pooled sera from 32 or 72 4CMenB-vaccinated infants in a serum bactericidal antibody assay in presence of human complement (hSBA). All infants had received four 4CMenB doses in the first 2 y of life. Baseline sera comprised 180 pooled samples from healthy-unvaccinated 2-month-old infants. Twenty of the 34 (59%) MATS-negative strains were killed in hSBA with titers ≥4 by pooled sera from vaccinated infants. There were 13/34 strains with hSBA titers ≥4 and at least a 4-fold rise in titer with respect to pooled baseline sera, and 10/34 with hSBA titers ≥8 and at least a 4-fold rise in titer with respect to baseline. These data confirm MATS as a conservative estimate for predicting strain coverage by 4CMenB.

Item Description

2164-5515
2164-554X
10.1080/21645515.2019.1688039