Vaccination with genetically modified Shiga-like toxin IIe prevents edema disease in swine.
Escherichia coli strains producing Shiga-like toxin II variant (SLT-IIe, formerly called SLT-IIv) cause edema disease in weaned pigs. Vaccination of pigs with a genetically modified form of Shiga-like toxin IIe, SLT-IIe(E167Q), has been previously shown to be nontoxic and to induce antibodies to SLT-IIe (V.M. Gordon. S.C. Whipp, H.W. Moon, A.D. O'Brien, and J.E. Samuel, Infect, Immun. 60:485-502, 1992). Fifty micrograms of SLT-IIe(E167Q) toxin was used to vaccinate suckling pigs at 1 and 2 weeks of age. Both vaccinated and nonvaccinated pigs were orally inoculated with an SLT-IIe-producing strain of E. coli after weaning (3 to 4 weeks of age). Pigs fed a low-protein diet that were not vaccinated with SLT-IIe(E167Q) developed subclinical edema disease, histologically evident as vascular necrosis. Pigs fed a high-protein diet that were not vaccinated with SLT-IIe(E167Q) developed clinical edema disease manifested as vascular necrosis, reduced weight gain, ataxia, palpebral edema, lateral recumbency, and death. Pigs vaccinated with SLT-IIe(E167Q) had a reduction in the incidence of subclinical edema disease and never developed clinical edema disease. These data demonstrate that vaccination with a genetically modified form of SLT-IIe prevents edema disease and are consistent with the notion that diet influences susceptibility to edema disease.
Bosworth
B T
BT
Physiopathology Research Unit, USDA Agricultural Research Service, Ames, Iowa 50010, USA.
Samuel
J E
JE
Moon
H W
HW
O'Brien
A D
AD
Gordon
V M
VM
Whipp
S C
SC
D000818:Animals; D000833:Animals, Suckling; D000907:Antibodies, Bacterial / Q000097:blood; D001427:Bacterial Toxins / Q000627:therapeutic use*; D001428:Bacterial Vaccines / Q000627:therapeutic use*; D004044:Dietary Proteins; D004488:Edema Disease of Swine / Q000517:prevention & control*; D004927:Escherichia coli Infections / Q000276:immunology / Q000662:veterinary*; D022641:Shiga Toxin 2; D013552:Swine; D014611:Vaccination / Q000662:veterinary*; D015430:Weight Gain
D000907:Antibodies, Bacterial; D001427:Bacterial Toxins; D001428:Bacterial Vaccines; D004044:Dietary Proteins; D022641:Shiga Toxin 2