Identification of the hypervirulent lineages of Neisseria meningitidis, the ST-8 and ST-11 complexes, by using monoclonal antibodies specific to NmeDI

Abstract

Most cases of serogroup C meningococcal disease are caused by the clonal lineages ST-8 and ST-11. The gene encoding the putative restriction-modification system NmeDI is specific to these lineages. We report here a monoclonal antibody directed against the NmeDI endonuclease as a tool for their rapid and spe-cific identification.

FIG. 1.

Dot blot showing the reactivity of meningococcal lysates with MAb 3/9-2. Representative meningococci of the Bavarian carrier isolate collection were used, including all strains harboring the gene for NmeDI. A1, positive-control strain 2120 (ST-11) (5); A2, negative-control strain MC58 (ST-74; donated by Richard E. Moxon, Oxford, England). Strains positive for the gene for NmeDI all reacted with MAb 3/9-2 (eight ST-11 complex strains, two ST-8 complex strains, four ST-44 complex strains, and one ST-914 strain), i.e., A3, B4 to -6; D2, -3, -5, and -6; E2 to -6; and F1 and -2. Genetically diverse strains lacking the gene for NmeDI did not react with MAb 3/9-2.