The Malaria Parasite – A Clever Chameleon

It’s difficult to envision conducting research on a minuscule mosquito, let alone on the one-cell parasite it transmits to humans – a deadly parasite that causes the most lethal form of malaria.

A groundbreaking discovery by Hebrew University researchers has cast new light on the parasite and how it evades the human immune system. Transmitted by a simple mosquito bite, the parasite takes up residence in the human liver and proceeds to multiply rapidly in the human bloodstream. To avoid the response of the human immune system, it modifies the surface of the red blood cells. When the immune system reacts, the parasite alters its identity by changing the surface protein it displays from among the 60 in its repertoire.

Prof. Ron Dzikowski and Dr. Inbar Amit-Avraham of the Faculty of Medicine’s Department of Microbiology and Molecular Genetics and the Sanford F. Kuvin Center for the Study of Infectious and Tropical Diseases pinpointed the RNA molecules that signal the parasite to “switch masks” each time it is threatened. Understanding this mechanism could reveal all of the parasite’s masks or leave it with only one mask. Either discovery would present the possibility of finding an effective way to block this response and enhance the development of new drugs and vaccines.

Prof. Dzikowski and his colleagues are working on attaining a basic understanding of how the parasite tricks the body, so “we can then trick it back,” he says with a grin. They are also collaborating with chemists and colleagues at the University and abroad to develop a drug that kills the parasite but is not toxic to humans. Funded by a substantial grant, that research is now moving into animal studies.

Efforts to eradicate malaria have so far proved ineffective – and the incidence of the disease continues to rise. “Developing a drug therapy,” Prof. Dzikowski says, “would be a major step forward.”

The next step:

Translational Research: Infectious and Tropical Diseases

From the earliest days of the 20th century, conditions endemic to the Middle East and the continuous influx of immigrants from different parts of the world afforded local scientists, researchers and clinicians both the challenge and the opportunity to diagnose, study and treat a staggering array of infectious and tropical diseases. Of necessity, they were involved in developing vaccines and vaccination protocols and monitoring outbreaks of a multiplicity of diseases.

Translational research into infectious and tropical diseases will build upon the Hebrew University’s earliest experiences and extensive knowledge to advance interdisciplinary research on the diagnosis, monitoring and control of infectious diseases, develop new vaccines, drugs and effective delivery systems and prevent the spread of these potentially lethal diseases.

More than 3.4 billion of the world's most vulnerable citizens are at risk of contracting malaria. In sub-Saharan Africa alone, malaria claims more than 450,000 lives each year, predominantly among children.