Protein could boost cancer immunity
Scientists have found a protein they believe can help boost immunity to cancer and viruses.
Researchers from Imperial College London say the discovery could open the door to new therapies.
The discovery surprised them as until now the new protein had no known function, and did not resemble any other protein.
Experiments on mice and human cells showed that it promoted an increase of cytotoxic T cells, which kill cancer cells and cells infected with viruses.
Researchers are now developing a gene therapy designed to boost the infection-fighting cells, and hope to begin human trials in three years.
The study, published in the journal Science, involved researchers at Queen Mary University of London, ETH Zurich and Harvard Medical School.
Claudio Mauro, who led the research from the Centre for Biochemical Pharmacology, based within Queen Mary University of London's William Harvey Research Institute, said: "This discovery has immediate consequences for the delivery of innovative therapeutic approaches to cancer.
"Its ramifications, however, are far greater as they can help explaining the biological mechanisms of widespread human diseases involving altered immune and inflammatory responses.
"These include chronic inflammatory and autoimmune disorders, such as atherosclerosis and rheumatoid arthritis."
When faced with serious infections or advanced cancer, Cytotoxic T cells are often unable to proliferate in large enough quantities to fight the disease.
But by screening mice with genetic mutations, the team discovered a strain of mice that produced 10 times as many of the cells when infected with a virus compared with normal mice.
They suppressed the infection more effectively, and were more resistant to cancer. They also produced more of a second type of T cells, memory cells, enabling them to recognise infections they have encountered previously and launch a rapid response.
The mice with boosted immunity produced high levels of a protein, which the researchers named lymphocyte expansion molecule, or LEM.
The study found that it is also effective in humans.
Study lead Professor Philip Ashton-Rickardt from the Section of Immunobiology in the Department of Medicine at Imperial, said: "Cancer cells have ways to suppress T cell activity, helping them to escape the immune system.
"Genetically engineering T cells to augment their ability to fight cancer has been a goal for some time and techniques for modifying them already exist. By introducing an active version of the LEM gene into the T cells of cancer patients, we hope we can provide a robust treatment for patients.
"Next we will test the therapy in mice, make sure it is safe and see if it can be combined with other therapies. If all goes well, we hope to be ready to carry out human trials in about three years."