Four researchers at the Stanford University School of Medicine have been awarded just over $5.5 million for their stem cell research projects.

The California Institute for Regenerative Medicine is now funding projects that are attempting to find ways to overcome immune system rejection of transplanted stem cells. The institute is the state stem cell agency created by Proposition 71, and on Tuesday it approved $25 million for 19 projects.

The California Institute for Regenerative Medicine has provided Stanford University with a total of about $173 million for various projects since the institute was established in November 2004.