If you ever find yourself putting a swimming parasite robot into a fish tank full of corn syrup, know that you’re likely to make a mess. This scenario is odd, I’ll admit, but it’s one that members of Stanford’s Prakash Lab found themselves in often.
They used robots, along with live observation and mathematical modeling, to investigate the unique swimming style of the larvae that infects humans with schistosomiasis, a crippling disease that disproportionately effects people living in impoverished areas. Their work is featured in the Stanford News Service video below.
Bioengineer Manu Prakash, PhD, (who was recently named a MacArthur Fellow) said he has worked on diagnostic tools for this disease in the field but found that current techniques for treatment and diagnosis are not enough. So, he decided to focus instead on targeting the parasite's ability to find a human host.
As part of this work, the researchers created simplified robotic models of the schistosomiasis larvae, some that exactly mimicked its stroke and others that moved in a modified style. They used corn syrup because its viscosity offset the difference in size between the robots and the larvae. The testing was explained in a press release:
With these models, they could make the model larvae do strokes that involved varying combinations of tail stiffness and bending movement. They even raced several robots, each with slight modifications in their tail stiffness.
'In many cases, we try to replicate nature in robots. This was very different,' said Deepak Krishnamurthy, a PhD student in the Prakash Lab and lead author of the study. 'On the face of it, it looks like I’m trying to make a robot that swims like a parasite, but the truth is that it was the exact opposite: I was building a robot to actually understand how the biological parasite swims.'
In the end, the researchers found the that the larvae’s real swimming stroke was quite impressive. It matched the optimal theoretical models they devised and the robot that most closely aligned with the real stroke outpaced all modified versions in the head-to-head race.
With these insights, Prakash and his lab members have returned to the field to collect more information about the real-world activity of these larvae. They want to further their understanding of how this parasite finds humans, hoping to apply that knowledge to reduce the reach of this devastating disease.
The research appeared recently in Nature Physics.
Previously: To control schistosomiasis, Stanford researchers advise thinking beyond pills, Discovered: Why so many people with schistosomiasis (there's a lot of them) are so vulnerable to bacterial co-infection and A new framework for expanding treatment guidelines for parasitic worm diseases