Word: marrow
(lookup in dictionary)
(lookup stats)
Dates: during 1980-1989
Sort By: most recent first
(reverse)
Just this past spring, scientists at U.C.L.A. announced that they had inserted foreign genes into the bone-marrow cells of mice, the first attempt at using new genetic-engineering techniques with living animals. But experiments on humans, experts said, were still years away. Not so. Last week it was disclosed that the great divide between research in mouse and in man had been quietly crossed...
...July, U.C.L.A. Hematologist Martin Cline and colleagues at Jerusalem's Hadassah Hospital on Mount Scopus and at a clinic of the University of Naples performed gene transfers on two female patients. Both had severe thalassemia, an inherited blood disorder in which the bone marrow produces red cells with defective hemoglobin (the molecule that carries oxygen to body tissues). Victims need frequent blood transfusions, but this leads to a buildup of iron in the body, particularly the heart, that can eventually cause death...
Cline and his collaborators treated their patients by removing a small amount of bone marrow and mixing it with genes capable of directing production of normal hemoglobin. The genes had been manufactured by bacteria altered by recombinant-DNA techniques. The marrow cells, now bearing the new genes, were then injected back into the patients. There is as yet no sign that their reconstituted marrow cells are producing healthy hemoglobin. But the story of the experiment, which was broken by the Los Angeles Times, has raised questions about whether the effort was premature. U.S. regulations require investigators to get approval...
...U.C.L.A. findings may eventually help patients undergoing cancer chemotherapy. Methotrexate, used to treat leukemia and other cancers, is like most antitumor drugs: potent but harsh. It indiscriminately destroys rapidly proliferating cells, malignant and healthy alike. Among the healthy ones are those of bone marrow, which produce blood cells. The damage that methotrexate does to bone marrow effectively limits how much of it can be given to patients. Making the cells resistant to the drug's assault might give patients the ability to withstand more intensive therapy...
Researchers also speculate that doctors might use the technique to correct blood diseases that result from defects in single genes, including sickle-cell anemia and thalassemia. The therapeutic gene could be transferred into bone marrow cells along with a gene for drug resistance. Exposure to the drug would kill off marrow that produces defective blood cells and allow a population of "cured" cells to take over...