Surgeons in Sweden have done something truly amazing.  After a patient with a cancerous tumor needed a windpipe transplant, surgeons  made a 3D replica of his windpipe out of glass and coated it with stem cells taken from his bone marrow.  Since this windpipe was grown using his own cells, there is no chance of rejection and no need for anti-rejection meds.  During a 12 hour procedure, Professor Macchiarini removed the tumor and damaged windpipe and replaced it with his lab-grown replica.