Sequence constancies and variations in genes encoding three new meningococcal vaccine candidate antigens.

By the strategy "reverse vaccinology" a number of new antigens have been identified in Neisseria meningitidis, which are potential candidates for a highly needed broad-spectrum meningococcal vaccine. In the present study we examined the prevalence, sequence constancies and variations of the genes encoding three of these new antigens designated, genome-derived neisserial antigen (GNA) 1870, GNA1946 and GNA2132. All three genes were present in all N. meningitidis isolates tested. Concerning gna1870, three major variants of the gene sequences and deduced amino acid sequences were identified and 56% of the deduced amino acids were conserved in all isolates. In gna1946, 98% of the deduced amino acids were conserved and in gna2132, 54% of the deduced amino acids were conserved. Based on gene prevalence and conservation, all three antigens are promising candidates for an effective meningococcal vaccine against all N. meningitidis irrespective of serogroup.