Just found this article and am wondering if there has been new light on this issue.
The Watchtower magazine of May 15, 1984:
Could a Christian accept a bone-marrow transplant, since blood is made in the marrow?
Doctors perform most bone-marrow transplants by withdrawing some marrow from a donor (often a near relative) and then injecting or transfusing it into the sick patient. They hope that the marrow graft will reach the patient’s marrow cavities and later function normally. Usually this procedure is considered only in critical cases (such as aplastic anemia or acute leukemia) for there are acknowledged hazards in preparing a person for a marrow graft and in treating him afterward.
As the question itself notes, red blood cells are formed in the marrow of certain bones such as the ribs, sternum and pelvic bones. Hence, it is understandable why, in the light of the Bible’s prohibition on blood, the question arises whether a Christian could accept a graft of human bone marrow.
The Bible states clearly that God’s servants must ‘abstain from blood.’ (Acts 15:28, 29; Deuteronomy 12:15, 16) But, since red cells originate in the red bone marrow, do the Scriptures class marrow with blood? No. In fact, animal marrow is spoken of like any other flesh that could be eaten. Isaiah 25:6 says that God will prepare for his people a banquet that includes “well-oiled dishes filled with marrow.” Normal slaughtering and drainage procedures never drain all blood cells from the marrow. Yet once a carcass is drained, then any of the tissue may be eaten, including the marrow.
Of course, marrow used in human marrow transplants is from live donors, and the withdrawn marrow may have some blood with it. Hence, the Christian would have to resolve for himself whether—to him—the bone-marrow graft would amount to simple flesh or would be unbled tissue. Additionally, since a marrow graft is a form of transplant, the Scriptural aspects of human organ transplants should be considered. See “Questions From Readers” in our issue of March 15, 1980. Finally, writing in Harrison’s Principles of Internal Medicine (Update I, 1981, page 138), Dr. D. E. Thomas observes that “virtually all marrow transplant recipients will require platelet transfusions” and many are given “packed red blood cells.” So the Christian should consider what additional issues he would have to face if he submitted to a marrow transplant.—Proverbs 22:3.
Though a personal decision has to be made on this matter, the Bible’s comments about blood and marrow should help the individual to decide.