title: Protective effect of recombinant staphylococcal enterotoxin A entrapped in polylactic-co-glycolic acid microspheres against Staphylococcus aureus infection.
abstract: Staphylococcus aureus is an important cause of nosocomial and community-acquired infections in humans and animals, as well as the cause of mastitis in dairy cattle. Vaccines aimed at preventing S. aureus infection in bovine mastitis have been studied for many years, but have so far been unsuccessful due to the complexity of the bacteria, and the lack of suitable vaccine delivery vehicles. The current study developed an Escherichia coli protein expression system that produced a recombinant staphylococcal enterotoxin A (rSEA) encapsulated into biodegradable microparticles generated by polylactic-co-glycolic acid (PLGA) dissolved in methylene chloride and stabilized with polyvinyl acetate. Antigen loading and surface properties of the microparticles were investigated to optimize particle preparation protocols. The prepared PLGA-rSEA microspheres had a diameter of approximately 5 μm with a smooth and regular surface. The immunogenicity of the PLGA-rSEA vaccine was assessed using mice as an animal model and showed that the vaccine induced a strong humoral immune response and increased the percent survival of challenged mice and bacterial clearance. Histological analysis showed moderate impairment caused by the pathogen upon challenge afforded by immunization with PLGA-rSEA microspheres. Antibody titer in the sera of mice immunized with PLGA-rSEA microparticles was higher than in vaccinated mice with rSEA. In conclusion, the PLGA-rSEA microparticle vaccine developed here could potentially be used as a vaccine against enterotoxigenic S. aureus.
authors.affiliation: Department of Clinical Medicine, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China. suzhang@cau.edu.cn.
authors.forename: Liben
authors.initials: L
authors.lastname: Chen
authors.forename: Shuang
authors.initials: S
authors.lastname: Li
authors.forename: Zhengfang
authors.initials: Z
authors.lastname: Wang
authors.forename: Ruilong
authors.initials: R
authors.lastname: Chang
authors.forename: Jingliang
authors.initials: J
authors.lastname: Su
authors.forename: Bo
authors.initials: B
authors.lastname: Han
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000627:therapeutic use*; D000818:Animals; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000276:immunology*; D004768:Enterotoxins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D005260:Female; D019344:Lactic Acid / Q000008:administration & dosage / Q000627:therapeutic use*; D051379:Mice; D011100:Polyglycolic Acid / Q000008:administration & dosage / Q000627:therapeutic use*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D013047:Specific Pathogen-Free Organisms; D013203:Staphylococcal Infections / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control*; D013211:Staphylococcus aureus / Q000276:immunology* / Q000472:pathogenicity; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D001428:Bacterial Vaccines; D004768:Enterotoxins; D014614:Vaccines, Synthetic; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; C026066:enterotoxin A, Staphylococcal