The process had been known for a while, but researchers got considerably better at recreating it artificially. :) The potential of this method for treating acquired autoimmunity and allergies looks big, to say the least. It is less likely to help against translplant rejection.
Hubbell and his colleagues knew that the body has a mechanism for ensuring that immune reactions don’t occur in response to every damaged cell in the body — a phenomenon known as peripheral immune tolerance, which is carried out in the liver. They discovered in recent years that tagging molecules with a sugar known as N-acetylgalactosamine (pGal) could mimic this process, sending the molecules to the liver where tolerance to them develops.