RESEARCHERS AT TRINITY College Dublin have established a link between serious autoimmune diseases like rheumatoid arthritis and the exposure to nanoparticles found in polluted air and smoke.

Environmental factors such as carbon particles emitted by car exhausts, smoking, and the long term inhalation of dust of various origins have long been recognised as contributory factors for chronic inflammation of the lungs – as has the link between smoking and autoimmune diseases.

However, the new findings have raised concerns about possible risks posed to global health by airborne pollutants from nanotechnology products that are not handled appropriately. The new findings will have health and safety implications for the future manufacture, use, and ultimate disposal of nanotechnology products and materials, according to the Nanomedicine and Molecular Imaging team at Trinity College Dublin’s School of Medicine.

The team, led by Professor of Molecular Medicine Yuri Volkov, also identified new cellular targets for the development of potential drug therapies in combating the development of  autoimmune diseases.

The team investigated whether there was a common underlying mechanism contributing to the development of autoimmune diseases in human cells following their exposure to a wide range of nanoparticles containing different physical and chemical properties. Over the course of their research, scientists applied a wide range of nanomaterials to human cells derived from the lining of the airway passages, and to the cells of so-called “phagocytic origin” (the cells  most frequently exposed to inhaled foreign particles or tasked with clearing the body of them).

TCD researchers collaborated with researchers from the Health Effects Laboratory Division, National Institute for Occupational Safety & Health (Morgantown, WV, USA) who had conducted the studies in mice exposed to chronic inhalation of air contaminated with single-walled carbon nanotubes.

The result, according to scientists, was “clear and convincing”. It showed that all types of nanoparticles – in both the TCD and US study – were causing an identical response in human cells and in the lungs of mice: the transformation of the amino acid arginine into the molecule citrulline, which can lead to the development of autoimmune conditions such as rheumatoid arthritis.

“The research establishes a clear link between autoimmune diseases and nanoparticles,” said Volkov.  ”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 possibly other autoimmune conditions.”

The findings that have been recently published in the international journal Nano medicine