Jeffrey Isner -- one of the nation's foremost authorities on gene replacement therapy -- died suddenly at age 53, cutting short his groundbreaking research on heart disease.

Boston [11.01.01] -- Jeffrey Isner's groundbreaking and innovative research in gene therapy offered a look at the future of medicine -- where doctors will be able to use raw genetic material to treat and cure everything from heart disease to cancer. While the Tufts professor and graduate won't see that vision become a reality, he will be remembered by the science community and the patients he treated as one of the pioneers who laid its foundation.

   Isner died on Wed. Oct. 31, at age 53, sending shock waves through Tufts and the medical community who had been closely watching the doctor's promising advancements in the relatively new field of gene replacement therapy.

   "Jeffrey has done a spectacular job in his chosen field of cardiology -- specifically in the gene therapy world. His work is truly revolutionary," Tufts' Medical School Dean John Harrington said on Thursday. "I've known Jeffrey since he was a medical student at Tufts in the early 1970s and have been a professional colleague of his for quite some time. We are all crushed at his loss and will miss him greatly."

   Dr. John Savio L.C. Woo, past president of the American Society for Gene Therapy, agreed.

   "Jeffrey is an outstanding visionary scientist who ... generated a lot of excitement," Savio told The Boston Globe. "If this field succeeds in the future, it will be his legacy."

   According to the Globe, "Isner, who had no history of heart disease himself, had been working for years to coax blood vessels to grow in patients whose hearts were too sick for bypass surgery and whose blood-starved limbs were threatened with amputation."

   His work earned admiration from throughout the medical community.

   Isner was awarded the Outstanding Faculty Achievement Award from Tufts in 1996 and the MERIT Award from the National Institutes of Health in 2000. The National Heart, Lung and Blood Institute just awarded Isner a "center of excellence" award in September.

   And his innovative findings attracted the attention of the national and international press.

   Last week, PBS' Scientific American Frontiers broadcast a segment on Isner's research -- crediting the Tufts graduate with developing one of the most promising applications for gene therapy: fighting heart disease.

   After seeing too many seriously ill patients he didn't know how to help, Isner was inspired by the work of renowned cancer researcher Dr. Judah Folkman. Since the 1970s, Folkman was trying to use genes to reduce the size of cancerous tumors.

   "These were generally very end-stage patients [who were ineligible for transplant or angioplasty] and we had very little to offer these people," Isner said in an interview for the PBS program. "One way to help them was to try to do the reverse of what Judah Folkman's lab was doing. They were trying to inhibit vascular growth and it occurred to use that we should encourage it."

   So he started working on a treatment that would do just that.

   "Isner's unique approach was to introduce a gene into ailing blood vessel cells that would stimulate the growth of new vessels around the blockage," reported PBS.

   The concept was unique. "As Isner puts it, it's like letting nature perform bypass surgery," reported the television show.

   Along the way, he was responsible for some major milestones in the field of gene therapy.

   In 1989, he injected the first genetically engineered human cells into the first human patient. Five years later, his team of scientists performed the first human cardiovascular arterial gene transfer in 1994.

   After learning of his death, Folkman said Isner's work "will have a lasting influence" for patients suffering from cardiovascular disease and cancer.

   Despite some national setbacks to gene therapy trials that postponed some of his ongoing research, Isner appeared to be making significant progress.

   Just prior to his death, he received a $10 million grant from the National Institutes of Health to continue his pioneering work.

   At St. Elizabeth's Medical Center -- a Tufts affiliate hospital where Isner created a nationally-renowned cardiovascular research program and conducted his research -- officials promised to continue the scientific journey he had begun.

   Calling him the "Pedro Martinez of our research staff," the president of the hospital's parent chain told the Globe that St. Elizabeth Medical Center will "honor Jeff's legacy and fulfill the promise of the research he so brilliantly pioneered."

   Thanks to Isner's lifetime of remarkable work, that promise won't be hard to keep.