1.   Transplants with transgenic pig organs?

2.   Alexion Pharmaceuticals Inc. received a U.S. patent for genetically engineered embryonic stem cells for use in the transplant of pig organs and tissue into humans, the company said.

3.   But significant hurdles remain before scientists will be ready to test pig organs in people.

4.   Hurdles remain before pig organs can be tested in humans.

5.   In all likelihood, the first transplants of pig organs will be temporary, to keep patients alive for weeks or months while they await a human organ.

6.   In recent years, a few patients have survived the wait for a human organ by being hooked up to a pig organ kept outside the body.

7.   Many investigators expect that if they could remove the pig gene responsible for adding that sugar molecule, then the pig organs would be more readily accepted by humans.

8.   Nextran, of Princeton, N.J., a subsidiary of Baxter Healthcare, is also working on transplanting pig organs to humans.

9.   Research reported at the Boston meeting revealed considerable progress toward using pig organs, often containing spliced-in human genes, for transplants.

10.   So the primate immune system kills the pig organs.