Now, researchers can use biological molecules called monoclonal antibodies that bind to cancer cells. Monoclonal antibodies can work alone or can be attached to anti-cancer drugs, radionuclides or toxins to deliver a deadly payload to cancer cells.

For the study, they used monoclonal antibodies that targeted specific sites on lymphoma cells to coat tiny structures called carbon nanotubes, which are very small cylinders of graphite carbon that heat up when exposed to near-infrared light.

This type of light, which is invisible to the human eye, is used in TV remote controls to switch channels and is detected by night-vision goggles. Near-infrared light can penetrate human tissue up to about 1½ inches.

The antibody-coated nanotubes are attached to the cells' surfaces in cultures of cancerous lymphoma cells. After exposing the targeted cells to near-infrared light, the nanotubes heat up, generating enough heat to essentially "cook" the cells and kill them. Nanotubes coated with an unrelated antibody neither bound to nor killed the tumour cells.

"Using near-infrared light for the induction of hyperthermia is particularly attractive because living tissues do not strongly absorb radiation in this range. Once the carbon nanotubes have bound to the tumour cells, an external source of near-infrared light can be used to safely penetrate normal tissues and kill the tumour cells," said Dr Ellen Vitetta, director of the Cancer Immunobiology Center at UT Southwestern and senior author of the study.

The new study is the first to show that both the antibody and the carbon nanotubes retained their physical properties and their functional abilities – binding to and killing only the targeted cells. This held true even when the antibody-nanotube complex was placed in a setting designed to imitate conditions inside the human body.

ANI