NEW HAVEN, Conn. (WTNH)– Yale researchers have developed a drug delivery system that could reduce organ transplant complications.

Researchers are using nano-particles to hide the donated tissue from the recipient’s immune system. The particles, made in a Yale lab, can be used to calm one of the main culprits behind organ rejection, white blood cells.

Researchers say they have had positive results in studies involving mice and will now look to apply the system to kidney transplants.

Yale says about 25,000 organ transplants are performed in the U.S. each year.