Related Experiment Videos
A pore-forming haemolysin from the hookworm, Ancylostoma caninum
Tegan A Don1, Malcolm K Jones, Danielle Smyth
1Division of Infectious Diseases and Immunology, Helminth Biology Laboratory, Queensland Institute of Medical Research, 300 Herston Rd, Brisbane, Qld 4006, Australia.
International Journal for Parasitology
|August 18, 2004
Summary
Dog hookworms lyse red blood cells using a heat-stable protein factor. This haemolysin creates pores in erythrocyte membranes, leading to cell lysis and blood feeding.
Area of Science:
- Parasitology
- Molecular Biology
- Biochemistry
Background:
- Hookworms are parasitic nematodes that feed on host blood.
- The mechanism by which hookworms lyse erythrocytes (red blood cells) for blood feeding is not fully understood.
Purpose of the Study:
- To investigate the mechanism of erythrocyte lysis by the common dog hookworm, Ancylostoma caninum.
- To identify and characterize the factor responsible for haemolysis.
Main Methods:
- Assessing haemolytic activity in detergent-soluble hookworm extracts across different life stages.
- Testing the stability of the haemolytic factor to heat, protease inhibitors, and other agents.
- Purifying the haemolytic factor using strong cation-exchange chromatography.
- Analyzing the interaction of hookworm proteins with erythrocyte membranes using microscopy and biochemical techniques.
Main Results:
- Ancylostoma caninum expresses a detergent-soluble, heat-stable haemolytic factor active in both adult and larval stages.
- The haemolysin is a protein, as indicated by its sensitivity to trypsin.
- Purified 60-65 kDa proteins from hookworm extracts exhibited trypsin-sensitive haemolytic activity.
- Scanning electron microscopy revealed pore formation (approximately 100 nm) in erythrocyte membranes after lysis, suggesting a pore-forming mechanism.
Conclusions:
- Ancylostoma caninum utilizes a novel protein haemolysin to lyse erythrocytes.
- This haemolysin likely functions by forming pores in the red blood cell membrane, leading to osmotic lysis.
- Understanding this mechanism could offer new targets for anti-hookworm therapies.