PLGA was used as a carrier for a divalent fusion DNA vaccine encoding the Aeromonas veronii
outer membrane protein A (ompA) and Aeromonas hydrophila hemolysins (hly) protein.
Loading of ompA-hly antigen module on PLGA microspheres were accomplished by waterin-
oil-in-water (W/O/W) encapsulation. Mice received ompA-hly antigen-loaded PLGA
microspheres by intraperitoneal or intragastric administration mounted strong and sustained
IgG response, which was significantly higher than those achieved by pET-28a-ompA-hly
antigen alone. OmpA-hly antigen-loaded PLGA microsphere vaccine uniquely conferred a
long lasting sterile immunity against challenge infection.