Scientists using a kind of microscopic surveillance system have snapped some of the sharpest images yet of malaria parasites breaking and entering into human cells.
Dr Jake Baum and colleagues from the Walter and Eliza Hall Institute in Melbourne and the University of Technology, Sydney, caught the deadly parasite in the act using super resolution microscopy, which provides images at a much smaller scale than normal light microscopes.
"The real breakthrough of super resolution microscopy is that it…basically allows you to build a three-dimensional image of cellular processes at very high resolution," says Baum. "It's like we've taken CCTV snapshots of thousands and thousands of bank-robberies."
Malaria, which is caused by the Plasmodium parasite, is transmitted by the bite of infected mosquitoes. Each year more than 400 million people contract malaria, and as many as a million, mostly children, die.
Using the new technology, the scientists have captured a detailed view of what occurs as the parasite burrows through the walls of red blood cells.
The results, which are published today in the journal Cell Host & Microbe, could provide new insights into the molecular and cellular events that drive cell invasion.
"It is the first time we've been able to actually visualise this process in all its molecular glory," says Baum.
Leap in detail
Although scientists have observed the parasite driving its way into cells before, the new technology provides a big leap in the amount of detail they can see.
"One of the most thrilling things we saw was the parasite inserting a ring-shaped protein into the cell wall to make a window through which it climbs," says Baum. "You can actually see the parasite climbing through."
He says this confirms findings from previous studies of other parasites.
Baum hopes the new knowledge will allow scientists new opportunities to "throw a spanner in the parasite's works".
"If, for example, you wanted to test a particular drug or vaccine, or investigate how a particular human antibody works to protect you from malaria, this imaging approach now gives us a window to see the actual effects that each reagent or antibody has on the precise steps of invasion."