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Published on: May 6, 2013
E. coli Lipopolysaccharide: acute oral toxicity study in mice
Marc S Harper1, Carol Carpenter, D J Klocke
1Pioneer Hi-Bred International Inc., Ankeny, IA 50021, USA.
Summary
Oral administration of Escherichia coli BL21(DE3) endotoxin to mice showed no toxicity, even at high doses up to 1,000,000 endotoxin units (EU). This study indicates that this specific endotoxin is safe when given orally to mice.
Area of Science:
- Toxicology
- Microbiology
- Pharmacology
Background:
- Endotoxins, such as lipopolysaccharide (LPS), are components of Gram-negative bacteria.
- Escherichia coli BL21(DE3) is a widely used strain for protein expression in molecular biology.
- The oral toxicity of bacterial endotoxins is not fully characterized.
Purpose of the Study:
- To evaluate the acute oral toxicity of endotoxin from Escherichia coli BL21(DE3) in mice.
- To determine the maximum tolerated dose (MTD) of orally administered E. coli endotoxin.
Main Methods:
- Groups of male and female CD-1 mice were administered single oral doses of E. coli BL21(DE3) endotoxin.
- Doses ranged up to 1,000,000 endotoxin units (EU) per mouse.
- Mice were monitored for 14 days for mortality, clinical signs, and body weight changes.
- Gross necropsy was performed at the end of the study.
Main Results:
- All mice survived the 14-day observation period across all tested doses.
- No clinical signs of toxicity were observed in any treatment group.
- No significant body weight loss or gross pathological lesions were noted during necropsy.
Conclusions:
- Oral administration of E. coli BL21(DE3) endotoxin up to 1,000,000 EU/mouse did not induce any observable toxicity in CD-1 mice.
- These findings suggest a low acute oral toxicity for this specific endotoxin preparation under the study conditions.
