Monday, August 24, 2009

The solution with a crystalline heart

A team at McGill University (and RI-MUHC) in Montreal is scrambling to create a malaria vaccine. The researchers, lead by Dr. Martin Oliver, "may have blazed a trail towards the development of vaccine-like treatments to limit the severity of the devastating parasitic ailment" (Science).

The team's new discovery may lead to the development of a medication that stops malaria from creating the debilitating inflammation that is associated with malaria. "Inside the human body, the malaria parasite infects red blood cells where it survives and reproduces by feeding on the cells' contents. Eventually the cells burst, releasing the parasites and also a waste byproduct of their reproductive process: hemozoin" (Tiemi). Hemozoin is the "chemically inert crystalline substance produced in the digestive food vacuole of blood-stage malaria parasites" (Parasitology).

Although chemically inert, it is still a foreign substance in the body. The Hemozoin is "one way by which the immune system is alerted to malarial infection." It "activates the immune system, resulting in the production of inflammation mediators and in the high fever." The researchers believe that hemozoin "may be the missing link that explains why malaria leads to devastating inflammation and fever...The researchers believe it will be possible to familiarize the immune system to small quantities of hemozoin and diminish the inflammatory response in the event of infection, according to a principle similar to that of vaccines" (Science). Dr. Olivier explains that "Now our picture of the process that goes from infection to fever is more or less complete."

However, a final solution is not yet apparent. "Malaria is too complex to be narrowed down to one single mechanism" (Tiemi). Although the relationship between hemozoin and inflammation is important, there are most like many other mechanisms at work.

Will a malaria vaccine ever be available? It is certainly possible, but more research and development is needed before we will know for sure.


Parasitology Encyclopedia. Hemozoin.

Tiemi Shio M, Eisenbarth SC, Savaria M, Vinet AF, Bellemare M-J, et al. Malarial Hemozoin Activates the NLRP3 Inflammasome through Lyn and Syk Kinases. PLoS Pathogens, 2009; 5 (8): e1000559 DOI: 10.1371/journal.ppat.1000559

Hempelmann, Birefringent Plasmodium falciparum hemozoin. [Photo]

Science Daily. "Towards Malaria 'Vaccine': Discovery Opens The Door To Malaria-prevention Therapies." 23 Aug 2009.

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