According to a study published in the journal Nanomedicine, researchers have found an association between exposure to nanoparticles and rheumatoid arthritis and the development of other serious autoimmune disease. In addition, the team discovered new cellular targets for developing potential drug therapies to treat autoimmune diseases.

Findings from the study, conducted by researchers at Trinity College Dublin, indicate that there are health and safety implications for the manufacture, utilization, and disposal of nanotechnology products and materials.

Smoking, carbon particles emitted by car exhaust, and inhalation of dust over the long-term are all risk factors which cause chronic inflammation of the lungs. In addition, researchers have also established an association between smoking and autoimmune diseases, such as rheumatoid arthritis.

In this study, the authors identified similar risks cause by nanotechnology products, which may produce new types of airborne pollutants that can impact global health if not handled appropriately.

In order to determine whether there was a common underlying mechanism contributing to the development of autoimmune diseases in human cells when exposed to nanoparticles, Professor of Molecular Medicine Yuri Volkov and his Nanomedicine and Molecular Imaging team at Trinity College Dublin’s School of Medicine, applied a wide range of nanomaterials to human cells derived from the lining of the airway passages, and to so-called phagocytic origin – cells that are more exposed to inhaled foreign particles or are responsible with eliminating them from the body.

The nanomaterials involved included, carbon nanotubes, ultrafine carbon black, and silicon dioxide particles of different sizes, ranging from 20 to 400 nanometers.

Meanwhile, scientists from the Health Effects Laboratory Division, National Institute for Occupational Safety & Health, Morgantown, WV, USA, conduced studies on mice exposed to long term inhalation of air contaminated with single walled carbon nanotubes.

In both the TCD and US study, the researchers found that all types of nanoparticles caused an identical response in the lungs of mice and in human cells, resulting in the specific transformation of the amino acid arginine into the citrulline molecule, which can trigger autoimmune diseases.

Human proteins which incorporate citrulline are unable to function normally and are destroyed and disposed of by the body’s defense system. Once citrullinated proteins are eliminated, the immune system begins to attack its own organs and tissues, thus causing the development of autoimmune diseases.

Professor Volkov explained:

“The research establishes a clear link between autoimmune diseases and nanoparticles. Preventing or interfering with the resulting citrullination process looks therefore as a promising target for the development of future preventative and therapeutic approaches in rheumatoid arthritis and possible other autoimmune conditions.”

Written by Grace Rattue