Wellington researcher gives parasitic worm its vaccine comeuppance
After getting sick from whipworms as a young boy, a Wellington researcher began a personal crusade against parasites affecting more than a billion people.
After getting sick from whipworms as a young boy, a Wellington researcher began a personal crusade against parasites affecting more than a billion people.
Malaghan Institute research director Graham Le Gros has long sought a cure for parasitic worms, including hookworm, a blood-sucker that bores its way into people's feet and into a nearby vein. Once there, it migrates up and into the lungs and hijacks a ride by getting coughed up into the throat, where it heads down into the gut.
There, the parasite latches on to the intestines by its teeth and happily makes a blood meal of its host.
"It's a bit like Alien."
When a mate comes along, a female hookworm can produce 30,000 eggs a day, all of which pass out through faeces and grow in the soil into larvae that will infect others.
The human body had no defense against hookworm and other soil-dwelling blood-sucking worms affecting a billion of the world's poorest, Le Gros said.
The Wellington professor spent some of his childhood in Singapore - "before Singapore became what Singapore is today" - where he had a case of whipworm in his gut.
"I remembered the medicine they used in those days to try and get rid of it. You just vomited and were sick the whole time."
Medical researchers had been trying for decades to develop a vaccine for this parasite, Le Gros said.
"It's subtle. It drinks just enough of our blood to not kill us but look after itself. It keeps on going around and around and around. So these people, from birth, are kept in a state of anaemia. Their brain doesn't develop very well."
Researchers believed parasites like hookworm had a special way of turning off the natural immune system response of the human body. So Le Gros and his team had to find a way to overcome this.
They had successfully delivered a vaccine into the lungs of a mouse which makes its immune system react to hookworm, taking advantage of a type of cell they recently discovered.
After receiving the vaccine, mice immune cells attack the worm and burst the parasite before it reaches the gut.
The research was published on Monday in the journal Nature Communications.
"It's got good implications for human disease. We're paying the hookworm back."
Le Gros hoped his findings would be used to create a human vaccine to fight tropical diseases related to parasitic worms.