Cell surface antigens of Bordetella pertussis

Cell surface-specific radiolabelling techniques, monoclonal antibody analyses, and chemical and physical isolation of cell fractions were used to study the surface of B. pertussis cells. Four surface specific proteins were identified by radioiodination and monoclonal antibody techniques. These included the filamentous hemagglutinin (FHA), and three outer membrane proteins-OMP91, OMP18 and OMP15. Membrane blebs were isolated from culture supernatants and shown to contain LPSII, pertussis toxin (PT), FHA, OMP91, and OMP18, but not OMP15. The level of LPS I in blebs appeared to be reduced from the level in cell envelopes. Bleb fractions contained enzymatically active adenylate cyclase (AC), and biologically active dermonecrotic toxin (DNT) and PT. Blebs were also toxic for mice, even when heated to 80 degrees C for 30 minutes. To explain these data, we propose that membrane blebs comprise an effective toxin delivery system, and that the cell surface of B. pertussis is composed of at least two domains.