Invasion plasmid antigen C (IpaC) (IpaC)

Invasion plasmid antigen C (IpaC) is a 42 kDa multifunctional protein essential for the virulence of Shigella flexneri 2a and other Shigella species [1, 5]. It serves as a key component of the Type III Secretion System (T3SS), where it works in complex with IpaB to form a translocon pore in the host cell membrane, facilitating the delivery of bacterial effectors into the host cytoplasm [5, 11]. Beyond its structural role, IpaC acts as an effector itself by inducing actin polymerization and subverting host cell signaling pathways, such as Rho-family GTPases, to trigger bacterial uptake into epithelial cells [3, 11, 16]. Because IpaC is highly conserved and critical for pathogenesis, it is a major focus for vaccine development, including subunit vaccines like Invaplex, mRNA-based vaccines, and nanoparticle-encapsulated formulations [1, 4, 14, 17]. These therapeutic approaches aim to elicit neutralizing antibodies that block the T3SS and prevent the invasion of the colonic mucosa, thereby protecting against shigellosis [1, 14]. Current research also explores the use of monoclonal antibodies to neutralize IpaC activity during infection [13].

Other names

IpaCInvasion plasmid antigen CipaCShigella flexneri 2a invasion plasmid antigen C

Induction of neutralizing antibodies to block bacterial invasion and inhibit Type III secretion system-mediated host cell entry [1, 14, 17].