
                         Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: WEDNESDAY, May 10, 1995                   TAG: 9505100069
SECTION: NATIONAL/INTERNATIONAL                    PAGE: A-3   EDITION: METRO 
SOURCE: Associated Press
DATELINE: LOS ANGELES                                LENGTH: Medium

GENE THERAPY HELPING BABIES WITH `BUBBLE BOY' DISORDER

The first attempt to treat a disease at birth with gene therapy shows early promise, say doctors who are using the procedure on three children born with the ``Bubble Boy'' immune-system disorder.

The children, the eldest of whom turns 2 this week, are developing well and making some immune cells of their own, the doctors said Tuesday.

``The study represents a major step toward gene therapy for the treatment of genetic diseases like sickle-cell anemia or immune deficiencies,'' said Donald B. Kohn, director of the gene therapy program at Children's Hospital Los Angeles. ``If we can correct genetic defects at birth, we can prevent the severe problems that follow.''

Kohn was to present the results of the project's first 18 months to the Society for Pediatric Research in San Diego today.

The children were born in May and June of 1993 with severe combined immunodeficiency. The disease, which usually results in death from infection before age 1, was caused by the lack of a gene that makes an enzyme called adenosine deaminase, or ADA.

People born without the gene must be kept isolated in a sterile plastic bubble because their bodies are unable to fight off any infections.

In a medical first, the Children's Hospital team used blood from the babies' umbilical cords as a source for stem cells, which are precursors to blood and immune cells. In adults, stem cells are harvested from bone marrow.

Doctors took the stem cells and added a normal ADA gene that had been transferred into a virus. The children then received transfusions of the corrective cells for three days.

The children also received ADA injections to help them fight off infections.

Nearly two years later, tests show some of those altered stem cells gave rise to normal disease-fighting cells called T-lymphocytes, the doctors said.

Now, doctors are slowly weaning the children off the injections, hoping they'll make more normal immune cells on their own.

``We are now up to 3 percent of their T-lymphocytes that have picked up the transferred genes,'' said Dr. Kenneth Weinberg, an immunologist and research team member. ``That represents a significant accomplishment. We don't yet know whether it's curative.''

by CNB