Scientists say they have cured diabetes in monkeys by giving them transplants of insulin-producing cells along with an experimental drug that prevented rejection of the donor tissue.  The findings are an important advance in diabetes research, "strikingly different" from all other previously tested strategies, and a step toward the ultimate goal of curing diabetes in humans, the scientists said.

Their findings involving the experimental drug known as anti-CD1S4 are to be reported later this year in the Proceedings of the National Academy of Sciences, which made the paper available ahead of publication.

Anti-CD154 is an artificially made antibody intended to thwart a key part of the immune system to ward off foreign tissue.  Experimental trials in humans have been approved by ethics committees and the Food and Drug Administration. They are expected to begin soon with support from the National Institutes of Health, said the researchers and the drug’s manufacturer, Biogen Inc. of Cambridge, Mass. But they refused to give details such as the starting date of the trials or the number of patients to beincluded.

Dr. Norma S. Kenyon, the lead author of the report from the University of Miami and the Navy, said the findings represented the most promising advance she had seen in 20 years.  "This may be something that is part of an eventual cure, but we do not want to mislead people by saying we have a final answer at this point and I do not want to raise false hopes," Kenyon said in an interview.

Nevertheless, Camillo Ricordi, a co-author of the report, said, "It is a major reason for cautious optimism."  The islet cells, which were transplanted into the monkeys, are the parts of the pancreas gland that produce insulin to control blood sugar. Islet-cell transplants have been carried out in more than 300 people in recent years, but with limited success, Ricordi said.

After a year, the graft has functioned in fewer than 35 percent of such patients and fewer than 10 percent have been able to stop taking insulin. Thousands more people have received transplants of the entire pan- creas gland, located deep in the abdomen.

However, a major problem with both islet cell and pancreas transplants is that each recipient would have to take a combination of powerful anti-rejection drugs for the rest of his life. The drugs increase infection risk an other complications, and can also promote development of diabe- tes, even in those without it.

To the Miami team, the most exciting finding was that they could safely prevent rejection with only one drug, not a cocktail of drugs. Also, the animals grew normally and suffered no infec- tions or other complications. Anti-CDl54 did not produce diabetes in the monkeys.

The experiments involved seven monkeys that were made diabetic by removing their pancreas glands.

[Reprinted from the NEW YORK TIMES]