A few years ago, a reader of the New York Times blog “Consults – Experts on the Front Lines of Medicine” (now replaced by Ask Well) posed the question “How does someone get scleroderma?” Leading expert Dr. John Varga responded “The cause of scleroderma is unknown. Viruses and exposure to certain chemicals and occupational toxins have been suspected, but nothing has been firmly proven to cause the disease.”
Since then, more research has been done and, a few days ago, results from a study published in the journal Science (December 5, 2013) provided evidence for a mechanism that may likely lead to the development of scleroderma – in an attempt to control cancer cells, the immune system attacks healthy tissues. The study, titled “Association of the Autoimmune Disease Scleroderma with an Immunologic Response to Cancer” was carried out by John Hopkins scientists.
Scleroderma is a group of diseases that affect the connective tissue – the tissue that supports the skin and the internal organs. In people with scleroderma, the affected tissue becomes hard or thick.
There are two main types of scleroderma. One is the localized type – this type often affects only the skin and does not harm major organs. The other one is the systemic type, which affects the skin, tissues under the skin, blood vessels, and major organs.
Paul Klee, one of the most inventive painters of the 20th century, was notoriously affected by the systemic scleroderma type. The somber tone of his late work is ascribed to the progression of the disease and chronic suffering. He wrote “If only the enigma of death were not so ambiguous! No less so is the enigma of life, for one has to wonder what beauty and splendor can be found in the torments of recent times.”
At the time, scleroderma was considered a mysterious disease. Now, we know that scleroderma is an autoimmune disease.
Patients with scleroderma produce autoantibodies – antibodies that cause tissue damage because they’re directed toward the patients’ tissues instead than toward foreign invaders. In scleroderma patients, the autoantibodies that cause tissue damage bind a protein called RPC1.
The John Hopkins scientists found that cancer cells from a majority of patients with severe scleroderma produce a mutated or “foreign” form of the RPC1 protein. This mutated form triggers production of antibodies able to bind the mutated RPC1 protein present in cancer cells. However, these antibodies are also able to bind the normal RPC1, which is present on healthy cells. In other words, in scleroderma patients, antibodies are produced to combat cancer but, in addition to destroying cancer cells, they also destroy healthy tissues.
“As early cancers grow, the body is exposed to novel proteins caused by the mutations in the cancer and potentially opens a window to development of autoimmune disease,” said Bert Vogelstein, Clayton Professor of Oncology at the Johns Hopkins Kimmel Cancer Center and a Howard Hughes Medical Institute investigator.
It is reasonable to speculate that, as more research is done, similar mechanisms will be identified for other types of autoimmune diseases.
Copyright © 2014 Immunity Tales.