Recombinant Human Anti-LF Antibody (IQNLF) (CAT#: HPAB-AP723-YC)

Figure 1 Toxin neutralization by IQNPA and IQNLF.

The abilities of both antibodies to neutralize a given amount of toxin were evaluated using the TNA assay (▵ and □). In order to determine if combining IQNPA and IQNLF had a positive or negative effect on neutralization, the two MAbs were mixed in various ratios prior to use in the assay (▴ and ▪). The results are expressed as the effective concentration of antibody that protected 50% of the cells in the assay (EC50).

Albrecht, M. T., Li, H., Williamson, E. D., LeButt, C. S., Flick-Smith, H. C., Quinn, C. P., ... & Groen, H. (2007). Human monoclonal antibodies against anthrax lethal factor and protective antigen act independently to protect against Bacillus anthracis infection and enhance endogenous immunity to anthrax. Infection and immunity, 75(11), 5425-5433.

Figure 2 rLF domain recognition by IQNLF.

Native Western blots probed with IQNLF. The gels were loaded with markers (left and right lanes) and the same concentration (50 ng) of each of the following constructs: full-length rLF (lane 1), LF domain I (lane 2), LF domain II (lane 3), LF domain III (lane 4), LF domain IV (lane 5), and LF domains II to IV (lane 6).

Albrecht, M. T., Li, H., Williamson, E. D., LeButt, C. S., Flick-Smith, H. C., Quinn, C. P., ... & Groen, H. (2007). Human monoclonal antibodies against anthrax lethal factor and protective antigen act independently to protect against Bacillus anthracis infection and enhance endogenous immunity to anthrax. Infection and immunity, 75(11), 5425-5433.

Figure 3 Protection of mice from an i.p. anthrax spore challenge by prechallenge injection of IQNPA and IQNLF.

Mice were inoculated i.p. with 180 μg of either IQNPA (n = 10) or IQNLF (n = 10) 2.5 h prior to an i.p. spore challenge consisting of 24 LD₅₀s. The MTD ± SD for the untreated controls was 87 ± 27 h. Twenty days later surviving mice were rechallenged with 41 LD₅₀s. In this second challenge the MTD ± SD for the controls was 69 ± 18 h.

Albrecht, M. T., Li, H., Williamson, E. D., LeButt, C. S., Flick-Smith, H. C., Quinn, C. P., ... & Groen, H. (2007). Human monoclonal antibodies against anthrax lethal factor and protective antigen act independently to protect against Bacillus anthracis infection and enhance endogenous immunity to anthrax. Infection and immunity, 75(11), 5425-5433.

Figure 4 Efficacy of IQNLF and IQNPA mAbs in restoring IL-8 protein production by HUVEC jr2 cells exposed to LT (5 nM PA and 0.5 nM LF).

* p < 0.05 for LT + 50 (25 ng IQNLF and 25 ng IQNPA per mL) compared to LT + 0 (no antibody treatment), # p < 0.05 (25 ng IQNLF and 25 ng of IQNPA combined compared to 50 ng of IQNLF or IQNPA), *** p < 0.001 for LT + 500 (500 ng IQNLF or IQNPA per mL or 250 ng of IQNLF and 250 ng of IQNPA per ml) compared to LT + 0.

Whiting, G., Baker, M., & Rijpkema, S. (2012). Development of an in vitro potency assay for anti-anthrax lethal toxin neutralizing antibodies. Toxins, 4(1), 28-41.