Neutrophil nanosponges soak up proteins that promote rheumatoid arthritis

Engineers at the University of California San Diego have developed neutrophil "nanosponges" that can safely absorb and neutralize a variety of proteins that play a role in the progression of rheumatoid arthritis. Injections of these nanosponges effectively treated severe rheumatoid arthritis in two mouse models. Administering the nanosponges early on also prevented the disease from developing. 

"Nanosponges are a new paradigm of treatment to block pathological molecules from triggering disease in the body," said senior author Liangfang Zhang, a nanoengineering professor at the UC San Diego Jacobs School of Engineering. "Rather than creating treatments to block a few specific types of pathological molecules, we are developing a platform that can block a broad spectrum of them, and this way we can treat and prevent disease more effectively and efficiently."

This work is one of the latest examples of therapeutic nanosponges developed by Zhang's lab. Zhang, who is affiliated with the Institute of Engineering in Medicine and Moores Cancer Center at UC San Diego, and his team previously developed red blood cell nanosponges to combat and prevent MRSA infections and macrophage nanosponges to treat and manage sepsis.

The new nanosponges are nanoparticles of biodegradable polymer coated with the cell membranes of neutrophils, a type of white blood cell.

Neutrophils are among the immune system's first responders against invading pathogens. They are also known to play a role in the development of rheumatoid arthritis, a chronic autoimmune disease that causes painful inflammation in the joints and can ultimately lead to damage of cartilage and bone tissue.