A cyst in a human brain populated by asexually produced clones, from the parasite Toxoplasmosis gondii. When these finger-like cells enter the bloodstream they can be killed using a novel technique.
Credit: DJP Feruson/University of Oxford
SYDNEY: A novel technique to kill parasites in the human body uses a combination of gold nanoparticles and lasers, and has been shown to work on Toxoplasmosis gondii - a common parasite that causes cysts in the brain.
Current treatments for parasites often have unwanted side affects on other cells in the body. This new technique is target-specific, opening up exciting new possibilities for the treatment of pathogenic parasites and possibly other infectious agents as well.
"No-one's succeeded in using this technology on parasites before" said Michael Cortie, a nanoscientist from the University of Technology Sydney (UTS). "This is great because we can localise disease treatment".
Toxoplasmosis: a common parasitic infection
Toxoplasmosis is a disease caused by the parasite Toxoplasmosis gondii, which infects one in three people worldwide, according to the University of Chicago Medical Centre. It is not often fatal, but can lead to other side effects such as an increase in risk taking.
The highly infectious parasite can affect healthy individuals, but it is most dangerous to people who are pregnant or immunocompromised as it can cause abortion, foetal abnormalities and encephalitis.
Until now, treatment for toxoplasmosis involved the use of antimalarial drugs or antibiotics, which may have serious side effects.
Gold nanoparticles and a laser
The researchers developed an alternative treatment involving gold nanospheres, about 20 nanometres in diameter (or 0.000002 cm).
When infected with a parasite, the human immune system produces an antibody - a protein - that selectively attaches to the parasite. The researchers coated gold nanospheres with this antibody so that the nanospheres attached to the parasite too.
The presence of the gold nanospheres in itself did not inhibit the parasite from continuing to infect cells.
A solution containing the parasite and nanospheres was irradiated with a laser, causing the nanospheres to heat up and kill the Toxoplamosis gondii organism.
The researchers say that the gold particles can be tuned to absorb wavelengths in the 'tissue window' - the range of wavelengths at which human tissues are transparent.
"This is a totally new idea in medicine as in general drugs go into the body and are taken up in the blood stream and go everywhere, so if it is a toxic drug, you feel rotten" Cortie said, who presented the results at the International Conference on Nanoscience and Nanotechnology in Sydney recently.
Brilliant
Another excellent article by this author