Parasite investigations breed 3 Tall Poppies
Three researchers from the Walter and Eliza Hall Institute in Melbourne, Australia, who are investigating different aspects of parasite biology have tonight been named Young Tall Poppies by the Australian Institute of Policy and Science.
Dr Justin Boddey, Dr Erinna Lee and Dr Chris Tonkin were among nine Young Tall Poppies from Victoria. Dr Tonkin was named Victorian Young Tall Poppy of the Year, receiving $5000.
Dr Tonkin is investigating how the Apicomplexan group of parasites invade human cells. In particular, he is interested in exposing the molecular mechanisms that activate cell invasion when these parasites come into contact with a human cell. This knowledge could reveal targets against which drugs can be developed to prevent parasite invasion.
"Apicomplexan parasites are a huge burden on humanity," Dr Tonkin said. "On one hand Toxoplasma gondii, the most abundant of all human parasites, infects between 30-80 per cent of the population and can cause congenital birth defects, spontaneous abortion and disease in people whose immune systems are compromised. Plasmodium falciparum, on the other hand is the cause of the most lethal form of malaria, infecting about 200 million people a year and killing about three million."
Dr Boddey is also trying to find ways to stop the malaria parasite. "Malaria involves large-scale infection of the blood stream after a bite from an infected mosquito," he said.
"The key to this disease is the parasite's ability to renovate red blood cells so that it can live inside them and hide from immune defenses. The parasite does this by delivering hundreds of specialised renovating proteins into red blood cells to transform them into diseased cells."
Dr Boddey's research has determined how the malaria parasite delivers these hundreds of renovating proteins into red blood cells and identified a single parasite protein that controls the process - a gatekeeper. "This gatekeeper protein is not present in humans and we are now developing a new drug that blocks it so that parasites can no longer modify the red blood cells they infect and, consequently, die," Dr Boddey said.
Death of a different kind is the subject of Dr Erinna Lee's research. Dr Lee is interested in apoptosis, the process by which damaged cells self-destruct.
Apoptosis is regulated by the pro-survival and pro-death proteins of the Bcl-2 family. "Dysfunctional apoptosis results in cancer, which arises when damaged cells fail to die and proliferate uncontrollably," Dr Lee said. "A class of anti-cancer drugs called BH3-mimetics have been developed that target the pro-survival proteins, triggering death."
Dr Lee is seeking to understand exactly how one BH3-mimetic, ABT-737, is successfully causing cell death.
In addition to her work on BH3-mimetics as anti-cancer therapeutics, Dr Lee recently discovered a number of Bcl-2 relatives in schistosomes, the parasites that cause schistosomiasis.
"Our preliminary studies show that ABT-737 binds the schistosome pro-survival protein. The next step is to establish the Bcl-2 family members essential for parasite survival, and provide proof-of-principle that targeting this pathway is a feasible anti-infective strategy."
Provided by Walter and Eliza Hall Institute