Several years ago, Prof. Cohen and colleagues developed a vaccine that arrests the progression of Type 1 diabetes in laboratory animals. They had discovered that a particular protein called HSP60, or even only a small particular fragment of it ?the peptide designated p277 ?is able to shut down the autoimmune response causing this disorder. The vaccine is currently being tested in clinical trials in Europe and the United States, but its precise mechanism has until now been unknown.
"When translating these findings into a practical vaccine, we knew enough about the mechanism to understand that this protein is able to cause a decrease in the immune response, but how it actually works eluded us," says Cohen. In a paper published in the Journal of Clinical Investigation, the scientists have managed to identify the exact immune cells that p277 acts upon and its mechanism of action.
Autoimmune diseases occur when certain T cells in the immune system attack the body's own cells and tissues. The scientists discovered that p277 directs the activity of the immune system in two ways. First, the p277 peptide steps up the activities of a different type of T cell that regulates the amount of potentially harmful T cells available. In addition, T cells treated with p277 cause the delinquent T cells to secrete anti-inflammatory substances instead of the inflammation-causing ones that they u
Source:American Committee for the Weizmann Institute of Science