Progress with pigs

The field of xenotransplantation has made dramatic scientific progress this year, with a number of technological advances that promise to drive development past the roadblocks to human clinical trials.

The obstacles have included the hyperacute rejection that occurs within minutes of xenotransplantation; a second event called acute humoral (vascular) rejection; worries about transmission of animal viruses (zoonoses) to humans; and the challenges of cloning pigs suited for organ donation...