Researchers at UC San Diego have developed a microscopic sponge that can soak up proteins that trigger rheumatoid arthritis, an autoimmune disease that causes chronic joint pain and inflammation.
“I think we have developed a breakthrough nano-medicine technology,” said Liangfang Zhang, a nano engineering professor at UC San Diego Jacobs School of Engineering and lead author of a study published Monday in "Nature Nanotechnology."
Zhang and his team developed neutrophil “nanosponges” to help combat and prevent the debilitating disease.
“A nanosponge is just a nano-particle,” Zhang explained. “The size is very small — it’s like a thousand times smaller than the width of your hair.”
The tiny particle is a round, biodegradable polymer coated with the cell membranes of neutrophils, a type of white blood cell.
“There’s no small molecule chemical drug inside, no biological antibodies involved — it’s just the two components,” he said “They will automatically degrade, leaving nothing toxic behind.”
Zhang calls the nanosponge a clever disguise because it acts like a decoy, appearing as a regular white blood cell, which is the body’s first responder against invading pathogens.
“In principle, it can be used to neutralize all different types of systemic or local inflammation, Zhang said. “We just chose rheumatoid arthritis as the first example to demonstrate the effectiveness of the neutrophil nanosponge.”
“They function like a sponge because they can absorb a lot of different types of the inflammatory factors of biomolecules,” Zhang added.
When injected in mice with severe rheumatoid arthritis, Zhang said it reduced inflammation and protected joints from further cartilage loss.
In recent years, he developed two other types of nanosponges, including one coated in red blood cells to fight infections by attracting toxins, such as drug-resistant staph bacteria and snake venom.
“It’s like one drug that you can use to treat all the different types of the 80 families of toxins,” he explained. “It can be used, in principle, to block all these biological molecules or chemical compounds or even parasite viruses, that attack or target human red blood cells,” he said.
He also developed macrophage nanosponges to treat and manage sepsis.
Zhang said he hopes to see his work soon in human clinical trials.
