A study by Weizmann Institute scientists has shown that embryonic stem cells may be able to repair damaged lung tissue and help alleviate chronic respiratory disease. Mice with damaged lungs were injected with these cells and in six weeks their breathing had improved. (Nature medicine)
http://www.israel21c.org/news/stem-cells-might-heal-damaged-lungs/
http://wis-wander.weizmann.ac.il/stem-cells-might-heal-damaged-lungs-0#.VajyU_nn-YA