A new experimental treatment developed by biotechnology firm LyGenesis may lead to patients growing an additional miniature liver. The approach involves injecting healthy liver cells into a lymph node in the upper abdomen of a patient with liver failure. The cells multiply and take over the lymph node to form a structure that can perform a liver's blood-filtering duties. The first person who received the treatment (on March 25) is recovering well, but they will need to be closely monitored for a while to see if the treatment is both safe and effective. The treatment has worked so far in mice, dogs, and pigs.