A Tick Closer to Understanding Lyme Disease
Lyme disease is on the rise. Higher global temperatures are part of the problem, helping ticks thrive. But it turns out, the infamous black legged deer tick that carries Lyme bacteria in North America has a secret weapon that scientists have just identified.
Tiny, blacklegged deer ticks, the ones that can carry Lyme disease, have long seemed like the magicians of the tick world. When they bite, they inject a sneaky bacterium, a molecule that tricks their hosts into thinking nothing’s amiss, until infection has already progressed.
“The molecule itself is fundamentally different from virtually all other bacteria,” according to Brandon Jutras, a biochemistry professor at Virginia Tech who has been studying Lyme disease in his lab.
“There's a really strong correlation and it’s likely, that this molecule is really driving some of the patient's symptomology, as it relates to late-stage Lyme disease known as Lyme arthritis.”
Jutras and his team first identified that elusive molecule in 2019 in a substance called Peptidoglycan. It’s a tiny mesh inside the tick that traps and hides the Lyme bacteria called Borrelia Burgdorferi. And that what leads to those late-stage symptoms of the disease known as Lyme arthritis.
“So, it really adds another level of complexity to the system because, in everyday life and everyday bacterial life, the bacteria that causes Lyme disease, --- this thing is just performing a basic function. It should be relatively innocuous, just one of the many proteins that bacteria make, that just help it perform basic physiological, activities.”
But now they know it’s more complicated than that. The team’s new discovery found a protein that, quietly and without a lot of warning, amps up inflammation in Lyme arthritis patients, messing with their immune systems. The newly identified protein is called “NAP –A” short for Neutrophil Attracting Protein A.
“And that actually, we think, acts as a decoy to allow the bacteria are alive or viable to escape, so that the rest of the bacteria can avoid the immune system initially. And then in later stages of disease and infection and in the case of say, Lyme arthritis, this molecule NAP-A is now pulling immune cells towards the peptidoglycan. And the peptidoglycan has those inflammatory properties and can cause arthritis."
And even though some other bacteria also have the NAP-A protein, Jutras says, “no one's ever shown that it's actually is, is interacting with peptidoglycan. So, it's kind of that the double-edged sword. Lots of bacteria have this protein, but again, normally performs a basic function inside the cell.”
But, he says, “This relationship between this protein, the peptidoglycan of Borrelia burgdorferi really kind of creates this Frankenstein interaction, that likely has really important consequences for what happens in human disease.”
Those scary sounding molecules may hold clues to diagnosis of Lyme disease, heretofore not an easy task, and Jutras say, it might even lead to development of a vaccine.
***Editor's Note: Radio IQ is a service of Virginia Tech.