‘Genetic messages’ between cells herald new way to tackle immune diseases

17 July 2014

Donor cells transfer miRNAs to prevent disease

Image: Donor cells transfer miRNAs to prevent disease

Scientists have discovered a new form of communication between cells - by sending 'genetic messages'.

The work, by a team at the Medical Research Council's National Institute for Medical Research (NIMR; now part of the Francis Crick Institute) and colleagues at Imperial College London, holds great promise for preventing inflammatory diseases such as asthma, colitis and autoimmune diseases.

Dr Mark Wilson of NIMR explained: "Cells must communicate with each other in the body to coordinate responses.

"In this breakthrough study, we have identified that cells send specific genetic material to other cells, instructing them to stop proliferating and stop secreting proteins."

The genetic messages are in the form of micro RNAs (miRNAs) - small strands of RNA that don't code for genes but instead regulate the expression of other genes. miRNAs regulate gene expression by binding to messenger RNA molecules (which are direct copies of genes) and preventing them from being translated into proteins.

The scientists generated 'recipient' cells that were deficient in miRNAs and grew these cells in the laboratory together with so-called 'sender' cells, which had miRNAs. They found that the recipient cells acquired miRNAs from the sender cells, showing that the genetic messages were being transferred between cells.

The team went on to identify that miRNAs are packaged into exosomes, small round structures which protect the miRNAs while in transit, and are delivered directly to inflammatory cells. By studying a model of colitis, an inflammatory disease affecting the gut, they found that this form of communication was important for cells to prevent inflammatory cells from causing intestinal disease.

Dr Wilson said: "Although these are very early days, if we identify how these genetic messages are regulated, both from the sender and by the receiver, we can manipulate this line of communication by directly targeting cells with miRNAs. This has implications for preventing inflammatory responses or enhancing immunity."

The findings also have much wider implications in biology. In particular, this new mechanism of communication may have implications for the development of cell-based therapies for cancer and degenerative disorders such as multiple sclerosis, as well as inflammatory diseases.

The paper, MicroRNA-Containing T-Regulatory-Cell-Derived Exosomes Suppress Pathogenic T Helper 1 Cells, is published in Immunity.

  • A new study led by the Medical Research Council's National Institute for Medical Research has found a new form of communication between cells, by sending 'messages' in the form of small pieces of RNA called micro RNAs (miRNAs).
  • The miRNAs are transferred from one cell to another where they regulate gene expression. They appear to play a role in preventing inflammation.
  • The work holds promise for treating not only inflammatory diseases such as asthma and colitis, but also cancer and degenerative diseases.