Scientists discover new role of antibodies

Lead researcher Alexander McLellan said the improved understanding of the immune system this research provides may lead to further improvements in vaccine design.  

"Our finding goes some way to explain the largely unsolved mystery of how the immune system gets kick-started. A major outstanding problem in immunology is how small amounts of infectious material can trigger strong immune responses at the start of infection," he said.  

Antibodies are released by specialised white blood cells, called B cells, following vaccination or previous exposure to pathogens and circulate around the body to provide long lasting protection in the blood and solid organs.  

The researchers have now shown that B cells use antibody to pull in tiny fragments of pathogens bound to the cell's surface and then recycle these to amplify the immune response.  

"Instead of destroying these fragments, we were surprised to find that B cells send them out again, still bound to antibody in a lipid particle, to further stimulate the immune system.  

"We believe our discovery of this recycling mechanism goes someway to explain why the immune system is an incredibly powerful bio-sensor, able to detect nanograms of pathogen material," McLellan said.