title: New Stx2e Monoclonal Antibodies for Immunological Detection and Distinction of Stx2 Subtypes.
abstract: BACKGROUND
  Stx2e is a primary virulence factor in STEC strains that cause edema disease in neonatal piglets. Though Stx2a and Stx2e are similar, many antibody-based Stx detection kits are designed to detect Stx2a and do not recognize the Stx2e subtype.
  
  
  RESULTS
  Four monoclonal antibodies against Stx2e were developed and characterized. Two of these mAbs recognize the B subunit of Stx2e, Stx2f, and to a lesser extent, Stx2b, Stx2c, and Stx2d. The other two mAbs recognize the A subunit of Stx2e, and cross-react with all Stx2 subtypes except Stx2f. The most sensitive sandwich ELISA using these mAbs has a limit of detection for Stx2e of 11.8 pg/mL. The ability of the neutralizing antibody Stx2e-2 to block Stx2e-receptor binding in Vero cells was visualized using immunofluorescence. Combinations of these and previously developed mAbs permit ELISA-based differentiation between closely related Stx2a, Stx2c, and Stx2d (using mAbs Stx2-5/2-1, Stx2-5/2e-2, and Stx2e-3/2e-2, respectively).
  
  
  CONCLUSIONS
  The sensitive immunoassays developed in this study should augment our capacity to detect Stx2e in porcine environments and biological samples. Moreover, immunoassays that can distinguish between the closely related Stx2a, Stx2c, and Stx2d subtypes can be useful in quickly analyzing Stx subtypes in samples containing more than one strain of STEC.
authors.affiliation: Western Regional Research Center, U.S. Department of Agriculture, Agricultural Research Service, 800 Buchanan Street, Albany, California, United States of America.
authors.forename: Craig
authors.initials: C
authors.lastname: Skinner
authors.affiliation: Western Regional Research Center, U.S. Department of Agriculture, Agricultural Research Service, 800 Buchanan Street, Albany, California, United States of America.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Patfield
authors.affiliation: Western Regional Research Center, U.S. Department of Agriculture, Agricultural Research Service, 800 Buchanan Street, Albany, California, United States of America.
authors.forename: Bradley J
authors.initials: BJ
authors.lastname: Hernlem
authors.affiliation: Western Regional Research Center, U.S. Department of Agriculture, Agricultural Research Service, 800 Buchanan Street, Albany, California, United States of America.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: He
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D002522:Chlorocebus aethiops; D004797:Enzyme-Linked Immunosorbent Assay; D004927:Escherichia coli Infections / Q000175:diagnosis* / Q000378:metabolism; D051379:Mice; D022641:Shiga Toxin 2 / Q000378:metabolism*; D014709:Vero Cells
chemical_list: D000911:Antibodies, Monoclonal; D022641:Shiga Toxin 2