title: Chicken egg yolk immunoglobulin (IgY) developed against fusion protein LTB-STa-STb neutralizes the toxicity of Escherichia coli heat-stable enterotoxins.
abstract: OBJECTIVE
  To obtain a recombinant enterotoxigenic Escherichia coli (ETEC) fusion enterotoxin protein LTB-STa-STb (Bab) that can express the immunogenicity of the haptens STa and STb and induce their corresponding neutralizing antibodies.
  
  
  RESULTS
  The three important ETEC enterotoxin genes coding LTB, STa and STb were PCR-amplified, and the amplified products were fused to construct the trivalent enterotoxin expression vector pET30-Bab. SDS-PAGE and Western blot were used to verify the expression of the fusion protein Bab by E. coli BL21 carrying plasmid pET30-Bab. Laying hens immunized with Bab developed high egg yolk immunoglobulin (IgY) titres specific to LTB, STa and STb, and all were significantly higher than those in the control group (P < 0·01). A suckling mouse assay showed that anti-Bab IgY can neutralize the natural toxicity of STa and STb with the highest dilution of 1/2 and 1/32, respectively.
  
  
  CONCLUSIONS
  Genetically constructed Bab induced significant antibody responses against STa and STb in chickens, and the resulting IgY had the capacity to neutralize the toxicity of ST.
  
  
  CONCLUSIONS
  The recombinant Bab protein containing three important ETEC enterotoxins may serve as an effective and convenient polyvalent toxoid that can be used to produce multiple antitoxin IgYs to prevent colibacillosis caused by ETEC with various fimbriae in young animals.
authors.affiliation: School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning, China; Postdoctoral Working Station, Dalian SEM Bio-Engineering Technology Co., Ltd., Dalian, Liaoning, China.
authors.forename: J
authors.initials: J
authors.lastname: You
authors.forename: Y
authors.initials: Y
authors.lastname: Xu
authors.forename: H
authors.initials: H
authors.lastname: Li
authors.forename: L
authors.initials: L
authors.lastname: Wang
authors.forename: F
authors.initials: F
authors.lastname: Wu
authors.forename: F
authors.initials: F
authors.lastname: Xu
authors.forename: L
authors.initials: L
authors.lastname: Jin
authors.forename: S
authors.initials: S
authors.lastname: Li
authors.forename: X
authors.initials: X
authors.lastname: Li
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology*; D057134:Antibodies, Neutralizing; D001427:Bacterial Toxins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000276:immunology* / Q000633:toxicity; D002645:Chickens / Q000276:immunology; D004530:Egg Yolk / Q000276:immunology; D054307:Enterotoxigenic Escherichia coli / Q000276:immunology; D004768:Enterotoxins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000276:immunology* / Q000633:toxicity; D029968:Escherichia coli Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000276:immunology* / Q000633:toxicity; D005260:Female; D007136:Immunoglobulins / Q000276:immunology*; D051379:Mice; D011993:Recombinant Fusion Proteins / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D057134:Antibodies, Neutralizing; D001427:Bacterial Toxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; C016512:IgY; D007136:Immunoglobulins; D011993:Recombinant Fusion Proteins; C034151:heat stable toxin (E coli)
keywords: diarrhoea; egg yolk immunoglobulin (IgY); enterotoxigenic Escherichia coli (ETEC); enterotoxin; immunogenicity; toxoid