Research: New treatments to prevent stomach ulcers and gastric cancer could follow from important new discoveries made by a Dublin-based research team, writes Dick Ahlstrom, Science Editor
They revealed how a bacterium linked to these diseases manages to take hold and colonise the stomach to cause later health problems.
The findings relate to an organism known as Helicobacter pylori, a bacterium known to cause stomach ulcers and also linked to cancer. The World Health Organisation has designated H pylori as a class I cancer causing agent.
"We have been interested in H pylori and how it colonises the stomach for a long time," said Dr Marguerite Clyne who, with co-author Prof Brendan Drumm, publishes the new findings this morning in the US Proceedings of the National Academy of Sciences.
Both are based in the Department of Paediatrics at University College Dublin and are investigators in the Conway Institute at Belfield. They conducted their research at the Children's Research Centre at Our Lady's Hospital for Sick Children, Crumlin, which also funded the study.
Why the organism was only found in the stomach has puzzled scientists for many years. The two Irish researchers have now answered that question - information that could lead to new, more effective treatments.
The longstanding assumption had been that H pylori colonised the stomach by binding to a receptor or docking station on the surface of a stomach cell.
The Dublin researchers looked instead at the protective coating of mucous that overlies stomach cells, studying in particular a family of small proteins found in the mucous called trefoil factors.
These factors protect the stomach cells by aiding healing after damage, Dr Clyne said. She and Prof Drumm found that H pylori attaches to a receptor site on one type of trefoil factor known as TFF1.
"We were able to show that the bacteria bind and bind well to TFF1," she said.
They also found that once the bacteria attached itself to the TFF1 it was able in turn to link itself to the mucous coating. In lab tests if there was no TFF1 present, the H pylori would simply wash away and could not attach to the mucous.
Epidemiological studies carried out by the H pylori research group at the Conway Institute had shown that infection with the bacteria almost always occurs in early childhood rather than in adult life. "You become infected quite young in life, usually before five," Dr Clyne said.
Many years later its presence can lead to ulcers and cancers.