Effect of Escherichia coli endotoxin on Archachatina marginata hemolymph coagulation system

Abstract

Context: Archachatina marginata Swainson (Achatinidae) is found in Nigeria, West Africa. Its hemolymph is applied as a disinfectant to blades and fresh cuts of circumcision in Yorubaland. The hemolymph is also used in traditional medicine practice. Investigation into its anti-endotoxin response is being studied for the first time.

Objective: This study determined whether endotoxin causes measurable and concentration-dependent protein coagulation in the separate hemolymph fractions and in hemocyte lysate (HL)/plasma mixtures.

Materials and methods: Endotoxin was prepared by inoculating 5% w/v dextrose with locally isolated Escherichia coli cells and incubated for 48 h before sterilization. Pyrogenicity was determined by rabbit test method and use the of LAL kit. Hemolymph fractions were exposed to endotoxin while controls were exposed to endotoxin-free water (0.025 EU/ml). HL/plasma (1:1 v/v) was exposed to varied endotoxin concentrations.

Results: Data indicated significantly higher protein coagulates induced by endotoxin in all the hemolymph fractions (P < 0.05). Maximum protein coagulation in mixture of HL/plasma 1:1 was recorded. Exposure of HL/plasma at optimal ratio to varied endotoxin caused linear protein coagulation up to 1.0 EU/ml, beyond which it dropped significantly and unresponsive to further increase in endotoxin doses.

Discussion and conclusion: There was endotoxin-induced protein coagulation, which is endotoxin concentration-dependent. The optimal coagulation observed for 1:1 HL/plasma mixture suggests stronger interaction between the hemocytes and the plasma in response to endotoxin. There are LPS-binding proteins in the plasma and hemocytes of A. marginata. This finding may be employed in detection and quantification of endotoxin in future.

Keywords::

• Escherichia coli
• Archachatina marginata
• invertebrate protein coagulation systems
• animal lectins
• endotoxin

Acknowledgement

We acknowledge the contributions of the Management of Biomedical Limited, Ilorin, Nigeria; Mrs. A. Amupitan and Miss Arinola Busari for the microbiological aspect of this work.

Declarations of interest

The authors report no declarations of interest. The authors alone are responsible for the content and writing of the article.