Recombinant vaccines based on translocated effector proteins of Salmonella Pathogenicity Island 2

Attenuated live Salmonella enterica are useful carriers for the delivery of heterologous antigens for vaccination. Effector proteins translocated by type III secretion systems (T3SS) of Salmonella have been successfully utilized for antigen delivery. Here we investigated the use of effector proteins of the T3SS encoded by Salmonella Pathogenicity Island 2 (SPI2). We observed that the effector protein SseF is suitable for delivery of various fusion proteins with heterologous antigens. The efficiency of this carrier protein was demonstrated in vaccination experiments with fusion proteins with Listeria monocytogenes protective antigens. SseF can thus be used as a versatile vehicle for translocation of heterologous proteins for vaccination.