New asthma target offers hope of more specific treatment

14 July 2014

Researchers have discovered a new genetic target for asthma treatment. 

The work, led by scientists at the Medical Research Council's National Institute for Medical Research (NIMR; now part of the Francis Crick Institute), provides pre-clinical evidence that targeting a micro RNA (miRNA) called miR-155 could alleviate asthma while avoiding the side effects of the broad-scale steroids that are currently used to treat this common and often debilitating condition.

Dr Mark Wilson of NIMR said: "Allergic diseases, such as asthma and allergic rhinitis, are some of the most common global chronic diseases. Currently, therapeutic intervention relies upon broad-scale steroids, which have indiscriminate impact and many side effects."

Dr Wilson's team studied a group of immune cells called Th2 cells, which are responsible for initiating and orchestrating the allergic cascade - a domino effect of reactions that occur in the body in response to an allergen.

They isolated Th2 cells from mice with allergic airway inflammation, which enabled them to identify new features of the allergic cascade, including new genes and miRNAs that are associated with Th2 cells but not other T cell populations.

The team found that inhibiting one of these miRNAS - miR-155 - prevented it from carrying out its function and significantly reduced the severity of airway inflammation in the mice.

Dr Wilson said: "This breakthrough study identifies a new therapeutic target, miR-155, that could be exploited to alleviate many of the symptoms associated with asthma.

"While this work focused on allergic asthma, the broader implications suggest that targeting miRNAs could be useful to treat many other inflammatory diseases, including multiple sclerosis, arthritis or diabetes."

The paper, Transcriptomics identified a critical role for Th2 cell-intrinsic miR-155 in mediating allergy and antihelminth immunity, is published in the Proceedings of the National Academy of Sciences.

  • Scientists at the Medical Research Council's National Institute for Medical Research (NIMR) have discovered that targeting a micro RNA found only in Th2 immune cells may alleviate asthma symptoms while avoiding the side effects of broad-scale steroids.
  • Micro RNAs (miRNAs) are small strands of RNA that don't code for genes but instead regulate the expression of other genes. They do this by binding to messenger RNA molecules (which are direct copies of genes) and preventing them from being translated into proteins.
  • The NIMR scientists worked with colleagues at the University of California in Los Angeles and the California Institute of Technology in Pasadena, USA.