Helicobacter pylori, the bacteria that causes ulcers, tricks the immune system so that the body can’t defend itself against the infection.
“By tricking the immune cells, the bacteria can keep the infection – and itself – alive,” Malin Hansson, a PhD student at Sahlgrenska, told TT news agency.
Around half of the earth’s population are carriers of the Helicobacter pylori. Most people aren’t affected by the bacteria at all, but it some individuals it can lead to ulcers or stomach cancer.
Research has shown that the immune system has a powerful reaction to the bacteria, which somehow entices the immune cells to remain at the site of the infection rather than travelling to the lymph nodes to activate more immune cells. The result is a chronic infection.
“Quite often it means ulcers and gastritis, which in the worst case can develop into cancer,” Hansson explained.
Her research also indicates that the antibodies that can protect the body against Helicobacter pylori are drawn to the infected tissue by a signalling molecule called MEC.
Many patients suffering from stomach cancer have very low levels of antibodies.
“If antibodies really protect against the development of stomach cancer, it should be possible to develop a vaccine that increases the excretion of MEC, which in turn draws more antibodies to the (infected) tissue,” Hansson said.
Her research has received international attention.
“This is basic research. But in the long term, it might mean that we can vaccinate against diseases such as ulcers and stomach cancer,” she added.
Australian researchers Barry Marshall and Robin Warren won the 2005 Nobel Prize in Physiology or Medicine for their discovery of Helicobacter pylori, which led to the treatment of ulcers with antibiotics.