During the very first few days of development of a cancer, our immune system recognizes cancer cells not as abnormal cells requiring eradication but as cells of the body that need to be protected. This result was obtained by the team led by David Klatzmann at the Laboratoire Immunologie (UPMC / CNRS / INSERM).
It could enable major advances in the treatment of cancer. This work was published in the Journal of Clinical Investigation on August 3, 2009.
Since the beginning of the 20th century, scientists have postulated the existence of the "immunosurveillance" of cancer, by which the immune system recognizes cancer cells(1) as being abnormal as soon as they are produced by the body, and then eradicates them. It is only when these cells escape from the immune response that a cancer develops. However, the team led by David Klatzmann, Professor at UPMC, has just revealed that this concept is inexact: the "immunosurveillance" of cancers does exist, but in fact it protects tumor cells when they appear, in the same way as any other normal cells in the body.
When an immune response is induced by the body, two types of lymphocytes (specialized immune system cells) are particularly closely involved: regulatory T-cells and effector T-cells. The former recognize components arising from the body itself and protect tissues from attack using the immune system. By contrast, effector T-cells specifically recognize foreign components and their function is to destroy them.