Fig. 5: Mechanism of action of acellular pertussis vaccine components.
From: Type 5 secretion system antigens as vaccines against Gram-negative bacterial infections
a Pertussis toxin (PT) elicits neutralising antibodies b Antibodies to FIM 2 and FIM 3 decrease bacterial adherence. c Anti-Pertactin antibodies activate the complement complex C1q resulting in (1) phagocytosis of bacteria or (2) formation of a membrane attack complex (MAC) on the surface of the bacterial cell, leading to lysis of bacteria. d FHA is secreted into the supernatant and anti-FHA antibodies decrease bacterial adherence. The crystal structure for PT was retrieved from PDB 1PRT. The structure for Pertactin was retrieved from AlphaFold database, UniProt accession Q8RSU0. The crystal structures for the N-terminal region of the passenger and translocator ___domain of FHA were retrieved from PDB 1RWR and 4QKY, respectively. The figure was created using components from BioRender.com, Alphafold, and PDB.
