THE FILAMENTOUS HEMAGGLUTININ OF BORDETELLA-PARAPERTUSSIS IS THE MAJOR ADHESIN IN THE PHASE-DEPENDENT INTERACTION WITH NCI-H292 HUMAN LUNG EPITHELIAL-CELLS

Bordetella parapertussis is a Gram-negative bacterium which colonizes the human respiratory tract and can cause whooping cough or pertussis. This pathogen is subject to phase variation and expresses a series of virulence factors exclusively in the Bvg(+) phase. Here, it is demons trated for the first time that only the Bvg(+) phase of B. parapertuss is adheres to and invades the human lung epithelial cell line NCI-H292 . A B. parapertussis mutant defective in expression of the Bvg(+)-regu lated filamentous hemagglutinin (FHA) showed reduced binding (77% redu ction) to NCI-H292 cells, as did a FHA mutant of the related Bordetell a pertussis (85% reduction). In contrast to B. pertussis, binding of B . parapertussis to NCI-H292 cells was not inhibited by heparin, sugges ting differences in the FHA adhesin and its host-cell receptor between these two species. Thorough understanding of the mechanism of action of the B. parapertussis virulence factors, such as FHA, is of particul ar interest in the development of novel strategies of pertussis vaccin ation. (C) 1998 Academic Press.