Mouse Anti-E. coli Stx2 Recombinant Antibody (clone 11E10) (CAT#: HPAB-S0137-YC)

Figure 1 Illustration of Stx1 and Stx2 and the initial chimeric toxins that contain hybrid Stx1/Stx2 A subunits and recognition or neutralization of those toxins by MAb 11E10.

The antibody reacted strongly with Stx2 and the chimeric toxins that contained the amino acids from the following regions of the Stx2 A subunit: 29 to 297, 1 to 158, and 29 to 128. MAb 11E10 neutralized Stx2 but did not neutralize Stx1.

Smith, M. J., Melton-Celsa, A. R., Sinclair, J. F., Carvalho, H. M., Robinson, C. M., & O'Brien, A. D. (2009). Monoclonal antibody 11E10, which neutralizes shiga toxin type 2 (Stx2), recognizes three regions on the Stx2 A subunit, blocks the enzymatic action of the toxin in vitro, and alters the overall cellular distribution of the toxin. Infection and immunity, 77(7), 2730-2740.

Figure 2 Western blot analyses and neutralization assays with Stx2 and Stx2 variants with MAb 11E10.

(A) Lane 1 contains 25 ng of purified Stx2. Lanes 2 to 5 contain the following toxins: lane 2, Stx2c; lane 3, Stx2d; lane 4, Stx2dact; lane 5, Stx2e. The Western blots were probed with either rabbit anti-Stx2 PAb (top panel) or MAb 11E10 (bottom panel). (B) Neutralization by 11E10 of the Stx2 variants. 11E10 neutralized all of the Stx2 variant toxins to ≥60% of the level of neutralization of Stx2.

Smith, M. J., Melton-Celsa, A. R., Sinclair, J. F., Carvalho, H. M., Robinson, C. M., & O'Brien, A. D. (2009). Monoclonal antibody 11E10, which neutralizes shiga toxin type 2 (Stx2), recognizes three regions on the Stx2 A subunit, blocks the enzymatic action of the toxin in vitro, and alters the overall cellular distribution of the toxin. Infection and immunity, 77(7), 2730-2740.

Figure 3 Protein synthesis inhibition measured by translation of luciferase mRNA in rabbit reticulocyte lysate.

Addition of 11E10 to the assay allowed protein synthesis to occur in the rabbit reticulocyte lysate even when Stx2 was present, whereas the isotype matched irrelevant antibody did not.

Smith, M. J., Melton-Celsa, A. R., Sinclair, J. F., Carvalho, H. M., Robinson, C. M., & O'Brien, A. D. (2009). Monoclonal antibody 11E10, which neutralizes shiga toxin type 2 (Stx2), recognizes three regions on the Stx2 A subunit, blocks the enzymatic action of the toxin in vitro, and alters the overall cellular distribution of the toxin. Infection and immunity, 77(7), 2730-2740.

Figure 4 MAb 11E10 alters the overall cellular distribution of Stx2 in Vero cells.

Stx2 appeared to be distributed throughout the cytoplasm in the absence of 11E10 but seemed to remain concentrated in largely perinuclear bodies in the presence of 11E10. When the cells incubated with the toxin-11E10 mixture were stained with antimouse IgG, 11E10 was observed in the same perinuclear punctate structures as Stx2. MAb 11E10 was unable to enter cells in the absence of toxin.

Smith, M. J., Melton-Celsa, A. R., Sinclair, J. F., Carvalho, H. M., Robinson, C. M., & O'Brien, A. D. (2009). Monoclonal antibody 11E10, which neutralizes shiga toxin type 2 (Stx2), recognizes three regions on the Stx2 A subunit, blocks the enzymatic action of the toxin in vitro, and alters the overall cellular distribution of the toxin. Infection and immunity, 77(7), 2730-2740.

Figure 5 MAb 11E10 prevented mortality and limited morbidity due to Stx2a i.g.intoxication.

In this preliminary study, complete mortality was observed in the Stx2a-only and Stx2a-plus-TFTB1 groups, while MAb 11E10 prevented mortality though not morbidity. Mice that received 4 μg 11E10 were completely protected, and in addition, their weight loss was reduced, although not to a statistically significant level.

Russo, L. M., Melton-Celsa, A. R., Smith, M. A., Smith, M. J., & O'brien, A. D. (2014). Oral intoxication of mice with Shiga toxin type 2a (Stx2a) and protection by anti-Stx2a monoclonal antibody 11E10. Infection and immunity, 82(3), 1213-1221.

Figure 6 Average weight over time in Stx2a-intoxicated mice given 11E10 (open symbols) or no treatment (filled symbols) 1 h before toxin administration.

All mice given 11E10 survived and had positive weight gain by day 14 postintoxication.

Russo, L. M., Melton-Celsa, A. R., Smith, M. A., Smith, M. J., & O'brien, A. D. (2014). Oral intoxication of mice with Shiga toxin type 2a (Stx2a) and protection by anti-Stx2a monoclonal antibody 11E10. Infection and immunity, 82(3), 1213-1221.

Figure 7 PAS-stained kidney sections from the MAb protection/Stx2a i.g. intoxication study.

The pathologist did not note any difference in kidney lesions between Stx2a-only- and TFTB1-treated, Stx2aintoxicated mice. ATN was also observed in mice given 11E10 and then i.g. Stx2a, although the lesions were minimal rather than moderate, and there was increased evidence of regeneration of distal tubules.

Russo, L. M., Melton-Celsa, A. R., Smith, M. A., Smith, M. J., & O'brien, A. D. (2014). Oral intoxication of mice with Shiga toxin type 2a (Stx2a) and protection by anti-Stx2a monoclonal antibody 11E10. Infection and immunity, 82(3), 1213-1221.