Chopped up proteins trigger autoimmunity

He has also discovered that PM/Scl-75, one of the components from which the exosome is built, is cut as soon as a cell dies. Finally, Schilders has identified an exosome-associated protein that is also frequently recognised by antibodies. These antibodies possibly form an interesting additional marker for the diagnosis of the PM/Scl overlap syndrome.

In people who suffer from an autoimmune disease, the immune system has been disrupted to such an extent that it produces antibodies against a person’s own substances. In polymyositis/sclerodermia (PM/Scl) overlap syndrome these antibodies are targeted at the exosome. This complex of proteins is involved in the degradation of RNA in the cell. RNA forms an essential link in the flow of information in a cell and, therefore, a strict control over the degradation of RNA is vitally important.

Source : Netherlands Organization for Scientific Research