快猫短视频

THE BELEAGUERED field of gene therapy has received a boost from a promising
new DNA treatment for the most common form of haemophilia.

Early tests of the method, which loads patients鈥� fat tissue with cells
containing DNA for factor VIII, a key clotting agent, have proved effective and
safe.

The tragic death of 18-year-old Jesse Gelsinger in a trial last year marked a
low point in the history of gene therapy. But in the past 12 months, impressive
results in treating inherited immune disorders, cancer and chest pain suggest a
revival is on the way.

Now David Roth of Beth Israel Deaconess Medical Center in Boston and his
colleagues report encouraging results from a non-viral form of gene therapy for
haemophilia. They took individual skin cells from six patients with severe
haemophilia A鈥攁 lack of factor VIII鈥攁nd introduced into each a
plasmid, a circular loop of non-viral DNA, containing the gene for factor VIII.
A single cell from each patient was then replicated until the researchers had
more than 100 million cells. These were injected into the patients鈥� belly
fat.

Although the trial was only designed to see if the therapy was safe, four of
the six patients showed significant improvement. One patient didn鈥檛 need any
additional factor VIII for three months. 鈥淭his had never happened before in his
life. It is unheard of,鈥� says Roth.

鈥淚 was pessimistic that this approach would produce enough factor for
therapy,鈥� says Paul Monahan of the University of North Carolina. 鈥淏ut these
strong results shows we have to keep an open mind about what might work.鈥�