T Cell Triumph; February 2003; Scientific American Magazine; by Diane Martindale; 2 Page(s)

Immunotherapy for cancer is a targeted treatment that uses a patient's own immune cells to attack and destroy tumors. Highly touted when it was conceived in the early 1980s, the approach has met with little success. Now researchers think they may have gotten over the hump: they have successfully treated several cases of a deadly skin cancer with immune cells taken from the patients, grown in large numbers in the laboratory and then given back to them. "We can now repopulate the body's immune system with cells that fight the cancer," says Steven A. Rosenberg of the National Cancer Institute, who pioneered immunotherapy.

The idea is to exploit a subset of T cells, the socalled tumor-infiltrating lymphocytes (TILs), found deep inside cancerous tissue. These killer T cells attack the rapidly dividing cells and provide a natural protection against cancer. But the body seldom makes enough to keep the disease in check.