Stem cell treatments permit transplant recipients to survive without immunosuppressant therapy. (Adapted from a CNN article).

When they were removed, Lindsey Porter’s kidneys were swollen and covered with cysts. The organs weighed around 7 kilograms.

While she waited for a transplant to treat her polycystic kidney disease Porter, 47, worried about the future. She was understandably pleased that she had found a donor, but did not look forward to a lifetime of taking immunosuppressant medicine.

“You get this brand new shiny kidney, and then they give you drugs that eventually destroy it,” Porter told CNN.

Hopefully for Porter, dependence on immunosuppressant medicine may not be as prominent in her future as she thought. Porter was one of the eight subjects who took part in a pilot study that found that stem cell therapy can trick patients’ bodies’ immune systems into thinking that the donated organ is its own organ. This phenomenon is known in medicine as “chimerism,” and patients in which it occurs are known as “chimera.”

“It has been an elusive goal to be able to do this in mismatched donor and recipient combos,” Dr. Joseph Levanthal, co-author of the study and a transplant surgeon at Northwestern Memorial Hospital, told CNN.

In the study, scientists at Northwestern University and the University of Louisville use bone marrow from the organ donor and strip out the cells in the marrow that might cause rejection. Later, the recipient of the organ is injected with the donor’s stem cells. With these cells in the recipient’s bloodstream, the patient’s immune system won’t attack the new organ.

Of the eight organ recipients who took part in the stem cell therapy, five had favorable results. One patient involved in the study had been without immunosuppressants for two years when CNN reported in 2012.

“Although only a taste of things to come, few transplant developments in the past half-century have been more enticing than these that put transplantation tolerance within our grasp,” James F. Markmann and Tatsuo Kawai, transplant experts at Massachusetts General Hospital, wrote to CNN.