As you may recall, the first big step in the stem cell transplant procedure that I underwent two years ago was the harvesting of my own stem cells. Over a period of several days I was given a drug (Neupogen) that stimulated the bone marrow's production of stem cells, and pushed them out into the blood stream. When there were enough of them out there, they were extracted (a process called "apheresis") and frozen for future use. This type of peripheral blood stem cell transplant, in which I was both the donor and the recipient of the stem cells, is called "autologous". In the other type of stem cell transplant, called "allogeneic", the donor and the recipient of the stem cells are different people. And according to the provisions of the National Organ Transplant Act, the donor must not be compensated for his or her role in the transaction.
The Act doesn't say so explicitly, though, because in 1984, when it became law, neither type of peripheral blood stem cell transplant existed. At that time, stem cells had to be extracted physically from the donor, in a process known as "aspiration" -- the same process I undergo when I get a bone marrow biopsy. It involves anesthetics, and big hollow needles that are pushed directly into the donor's bones. Except whereas just a small amount of marrow is quickly extracted for a biopsy, a great deal more must be taken for a bone marrow transplant. It's a lengthy, dangerous and painful process for the donor, which is why bone marrow donors have traditionally been difficult to come by, and why this older type of bone marrow transplant has been progressively replaced by peripheral blood stem cell transplants. But the anti-compensation provisions of NOTA have been assumed to apply uniformly to stem cells, irrespective of the method of their extraction, even though the law's text necessarily refers only to bone marrow extracted via aspiration.
Until now, maybe. Recently the 9th U.S. Circuit Court of Appeals ruled that stem cells extracted by apheresis are more akin to ordinary blood than to an "organ" -- it has always been possible to pay people for their blood -- and that therefore NOTA does not apply to stem cells extracted via apheresis. It hardly need be said that such a ruling is controversial -- it's thought by some to represent a "camel's nose" for the eventual development of a market in organs -- and is probably headed for final resolution by the U.S. Supreme Court, if Their Honors are interested.