Gold vs. Rheumatoid Arthritis and Other Autoimmune Disease: Mystery Solved?

Gold has been used to treat Rheumatoid Arthritis (RA) since the 1930s. Now Harvard Medical School researchers have discovered why gold (and platinum) works against autoimmune disorders. Their research is reported in the 27 February issue of Nature Chemical Biology. From eurekalert pub releases:

"We were searching for a new drug to treat autoimmune diseases," says Brian DeDecker, PhD, HMS post-doctoral student in the Department of Cell Biology and a study co-author. At the time of this work, DeDecker was in the Harvard Medical School Institute of Chemistry and Cell Biology, which uses powerful chemical tools to illuminate complex biological processes and provide new leads for drug development. "But instead we discovered a biochemical mechanism that may help explain how an old drug works."

....During their search through thousands of compounds they found that the known cancer drug, Cisplatin, a drug containing the metal platinum, directly stripped foreign molecules from the MHC class II protein. From there, they found that platinum was just one member of a class of metals, including a special form of gold, that all render MHC class II proteins inactive.

In subsequent experiments in cell culture, gold compounds were shown to render the immune system antigen presenting cells inactive, further strengthening this connection. These findings now give researches a mechanism of gold drug action that can be tested and explored directly in diseased tissues.

Put differently, gold and platinum interfere with MHC class II proteins, "slowing down" the immune system a bit. By giving the immune system a rest, inflammation in the joints and other body tissues is allowed to subside. Scientists will now take this knowledge of how these precious metals modify immune function, and devise new and better drugs with fewer side effects.

Gold is being studied as a nano-therapy, to treat Alzheimer's and to introduce drugs into cells. The unique effect of gold and platinum on the immune system makes them potentially valuable materials for implants.

Read the entire release here.