title: Immunogenicity of recombinant Lactobacillus casei-expressing F4 (K88) fimbrial adhesin FaeG in conjunction with a heat-labile enterotoxin A (LTAK63) and heat-labile enterotoxin B (LTB) of enterotoxigenic Escherichia coli as an oral adjuvant in mice.
abstract: OBJECTIVE
  The aims of this study were to develop an effective oral vaccine against enterotoxigenic Escherichia coli (ETEC) infection and to design new and more versatile mucosal adjuvants.
  
  
  RESULTS
  Genetically engineered Lactobacillus casei strains expressing F4 (K88) fimbrial adhesin FaeG (rLpPG-2-FaeG) and either co-expressing heat-labile enterotoxin A (LTA) subunit with an amino acid mutation associated with reduced virulence (LTAK63) and a heat-labile enterotoxin B (LTB) subunit of E. coli (rLpPG-2-LTAK63-co-LTB) or fused-expressing LTAK63 and LTB (rLpPG-2-LTAK63-fu-LTB) were constructed. The immunogenicity of rLpPG-2-FaeG in conjunction with rLpPG-2-LTAK63-co-LTB or rLpPG-2-LTAK63-fu-LTB as an orally administered mucosal adjuvant in mice was evaluated. Results showed that the levels of FaeG-specific serum IgG and mucosal sIgA, as well as the proliferation of lymphocytes, were significantly higher in mice orally co-administered rLpPG-2-FaeG and rLpPG-2-LTAK63-fu-LTB compared with those administered rLpPG-2-FaeG alone, and were lower than those co-administered rLpPG-2-FaeG and rLpPG-2-LTAK63-co-LTB. Moreover, effective protection was observed after challenge with F4+ ETEC strain CVCC 230 in mice co-administered rLpPG-2-FaeG and rLpPG-2-LTAK63-co-LTB or rLpPG-2-FaeG and rLpPG-2-LTAK63-fu-LTB group compared with those that received rLpPG-2-FaeG alone.
  
  
  CONCLUSIONS
  rLpPG-2-FaeG showed greater immunogenicity in combination with LTAK63 and LTB as molecular adjuvants.
  
  
  CONCLUSIONS
  Recombinant Lactobacillus provides a promising platform for the development of vaccines against F4+ ETEC infection.
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: M
authors.initials: M
authors.lastname: Yu
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: R
authors.initials: R
authors.lastname: Qi
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: C
authors.initials: C
authors.lastname: Chen
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: J
authors.initials: J
authors.lastname: Yin
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: S
authors.initials: S
authors.lastname: Ma
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: W
authors.initials: W
authors.lastname: Shi
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Wu
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: J
authors.initials: J
authors.lastname: Ge
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: L
authors.identifier: http://orcid.org/0000-0002-2423-0076
authors.initials: L
authors.lastname: Tang
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Xu
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Li
mesh_terms: D018830:Adhesins, Escherichia coli / Q000235:genetics / Q000276:immunology*; D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000284:Administration, Oral; D000818:Animals; D001427:Bacterial Toxins / Q000008:administration & dosage / Q000276:immunology*; D054307:Enterotoxigenic Escherichia coli / Q000145:classification / Q000276:immunology*; D004768:Enterotoxins / Q000008:administration & dosage / Q000276:immunology*; D004927:Escherichia coli Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary; D029968:Escherichia coli Proteins / Q000008:administration & dosage / Q000276:immunology*; D022361:Escherichia coli Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D005260:Female; D010861:Fimbriae, Bacterial; D018928:Immunity, Mucosal; D007780:Lacticaseibacillus casei / Q000235:genetics*; D008214:Lymphocytes / Q000166:cytology / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D013047:Specific Pathogen-Free Organisms; D013552:Swine; D013553:Swine Diseases / Q000276:immunology / Q000517:prevention & control
chemical_list: D018830:Adhesins, Escherichia coli; D000276:Adjuvants, Immunologic; D001427:Bacterial Toxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D022361:Escherichia coli Vaccines; C494388:FaeG protein, E coli; C027538:heat-labile enterotoxin, E coli
keywords: 
  Lactobacillus casei
  ; fimbriae adhesin FaeG; heat-labile enterotoxin A subunit; heat-labile enterotoxin B subunit; immunogenicity