http://news.bbc.co.uk/2/hi/health/4563994.stm

Press release (more in-depth): http://www.eurekalert.org/pub_releases/2005-12/hhmi-slm122705.php

Invisibility cloaks and malaria

Plasmodium falciparum – Institut Pasteur
Not wearing invisibilty cloak in this pic 😉

The world’s deadliest malaria parasite, Plasmodium falciparum, sneaks past the human immune system with the help of a wardrobe of invisibility cloaks. If a person’s immune cells learn to recognize one of the parasite’s many camouflage proteins, the surviving invaders can swap disguises and slip away again to cause more damage.

The latest study shows how the parasite can turn on one cloaking gene, and keep dozens of others silent until each is needed in turn. The key is a DNA sequence near the start of a cloaking gene, known as the gene’s promoter. This not only turns up production of its protein, but also keeps all other cloaking genes under wraps.

    “It’s like a leopard being able to change its spots. New forms come up, and the immune system beats them down again. Because of this a lot of people think you need five years of constant exposure to malaria in its different disguises to gain immunity.”

Many children do not survive malaria long enough to develop immunity. And without continuous exposure, hard-won immunity may disappear.

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