Four paralysis patients are responding positively to a new treatment that regenerates damaged cells in the central nervous system, which was long believed to be impossible. Dr. Valentin Fulga of Proneuron, based in Nes Tzionah south of Tel Aviv, says clinical trials on the four have shown "encouraging results."

Melissa Holley, treated in July 2000 at the Sheba Medical Center at Tel Hashomer, was showcased on CBS-TV's "48 Hours" in mid-June. Doctors thought Holley, 20, of Colorado, whose vertebrae were crushed in a car accident, would be confined to a wheelchair for life. It took only three months, instead of the 6-12 projected, for her to start regaining feeling and control in her legs and lower body. Doctors now think she'll be able to walk again.

The treatment - which has also been used on three Israelis - uses blood taken from patients within 12 days of injury, and "teaches" its white corpuscles to induce healing by incubating them alongside a skin sample. The cells, called macrophages, are then injected into the patients' spines.

Macrophages are part of the normal healing process. But usually, says Fulga, "the central nervous system inhibits the immune system from initiating regeneration," to protect itself against the production of new cells which might damage it. Proneuron's system, according to Fulga, injects the missing macrophages which allow regeneration.

Proneuron's technology was discovered in work on mice by its founder, Prof. Michal Schwartz of the Department of Neurology at the Weizmann Institute in Rehovot. The firm hopes to utilize the same scientific base to slow cell-degenerative disorders like glaucoma, and to rein in the immune system when it acts uncontrollably as in Parkinson's and Alzheimer's disease.

Proneuron plans to conduct additional tests at clinics in the U.S. and Europe within a year.