Neisserial surface variation: how and why?

Neisseria gonorrhoeae exhibits striking variability in several of its surface components (pili, Opa proteins and lipooligosaccharide) in vivo and in vitro. Such flagrant variation of this mucosal pathogen's surface components contrasts sharply with changes in single surface components of blood-borne trypanosomes and borreliae. Despite these differences, similar molecular events are sometimes involved.