Understanding Interactions Between Eosinophils and Tissue-Invasive Parasitic Helminths [ 2001 - 2003 ]

Research Grant

Researchers: Dr Lindsay Dent (Principal investigator) ,  Prof David Gordon

Brief description Eosinophils are blood cells which contribute to our defences against parasitic worms. Given the right opportunity, eosinophils can cause damage to some parasites within just a few hours of contact. This is quite a feat because parasitic worms are multicellular organisms which are much larger than eosinophils and which have evolved to live in the presence of active immune responses. To do it's job properly an eosinophil probably makes use of small soluble molecules in the blood and others fixed to it's own cell surface, to recognize the parasite and to promote adhesion to the target. You might like to consider these molecules as hands grabbing onto handles on the surface of the parasite. The more hands there are, the better the grip and some hands grip more strongly than others. We are investigating what these molecules are and how they work. By understanding how eosinophils operate, we may be able to devise ways in which we can make them more effective. We are also trying to understand why some species of parasite are resistant to attack by eosinophils. We think that resistant parasites secrete substances which either block the binding of eosinophils to the parasite surface, or prevent the functioning of eosinophils that do bind. It is possible that these inhibitory substances may even kill the eosinophils before they can do their job. Resistant parasites might induce eosinophils to commit suicide, a useful property for us when we no longer need these cells, but a definite drawback if they still have a job to do. Parasitic worms have evolved to avoid at least some of our defences and sometimes they do this by mimicing natural processes important for regulating immune responses. In some diseases like asthma and allergy eosinophils slip from normal controls which regulate them and then they can cause tissue damage. Inhibitors of eosinophils which are produced by parasites might form the basis of new drugs to control these cells in diseases like asthma.

Funding Amount $AUD 227,545.90

Funding Scheme NHMRC Project Grants

Notes Standard Project Grant