Discovery to Eliminate Complications Occurring in Tissue Transplantation

A Harvard researcher has discovered a way to treat cells that prevents the body's immune system from attacking the cells during transplants.

This finding may eventually lead to a reduction in the complications resulting from efforts to prevent the rejection of transplanted organs.

Denise L. Faustman, assistant professor of medicine at the Medical School, co-authored a paper discussing the results in the June 21 issue of Science.

Transplantation Process

According to Faustman, the body normally rejects any transplanted foreign tissue. This rejection occurs by way of a special type of white blood cell, called a T-lymphocyte, or a T-cell.

"T-lymphocytes generally swim by and attach onto the surface of foreign cells," Faustman says. They have a "memory" which allows them to promptly attack a previously identified coding region, or epitope, on the cell.

When tissue is transplanted, "the standard method is to treat the recipient to suppress the T-cell response," according to Faustman. She says that drugs called immuno-suppressive agents are often used for this purpose.

Faustman's research will "instead treat the tissue [to be transplanted] with agents that prevent the T-cells from adhering to it," she says, "thereby eliminating the need for therapy of the host and its inevitable complications."

Future Applications

So far, her experiments have utilized human pancreatic islets and parenchymal liver tissue transplanted into the kidneys of mice, Faustman says.

She says that her technique "may be applicable to whole organ transplants, but more research is necessary."

"The thing about whole organ transplants is that you are putting an enormous amount of foreign cells into the body," Faustman says.

"I don't think it will be directly applicable to organ transplants," she says, "but it may help suppress the immune response."

Faustman is currently planning a continuation of the project. "We are trying to apply it to different kinds of cells and to higher organisms," she said. "It's good because the antibodies are directly applicable to humans."