Structure and immunochemistry of meningococcal lipopolysaccharides

The structures of the largest dephosphorylated oligosaccharides (OS) obtained by mild acid hydrolyses of the L2, L3 and L5 serotype lipopolysaccharides (LPS) of Neisseria meningitidis have been elucidated. The OS have extensive regions of structural similarity of which some are responsible for cross-reactivity among the meningococcal LPS. However, the fact that the LPS are predominantly serotype-specific antigens implies that the terminal lacto-N-neotetraose unit, common to all the above OS, is not immunodominant, and that the major LPS serotype specificity originates in the inner core region of the OS.