Specialised immune cells have potential for new cancer immunotherapies
Researchers from Leiden University Medical Center (LUMC) and Netherlands Cancer Institute (NKI) have discovered how specialised immune cells can detect and remove cancers that are ‘invisible’ to the conventional defence mechanisms of the immune system. Their work has been published in Nature. The findings could lead to novel cancer immunotherapies.
Identifying abnormal cells in our body is usually a task for T cells, one of the most important white blood cells in the immune system. These cells can recognise many types of abnormality, including viral and bacterial infections. But the immune system sometimes has trouble detecting cancer cells. These are only recognised by T cells if a specific molecule is attached to their surface. To escape immune recognition, some cancers lack such molecules and become ‘invisible’ to T cells.
Why does immunotherapy work in these patients?
Researchers from the LUMC and NKI recently stumbled upon a strange phenomenon: some patients with ‘invisible’ cancers respond well to cancer immunotherapies. These therapies rely on antibodies that activate or reinvigorate the activity of T cells. ‘Since these cancers lack the molecules that enable T cells to identify them, we did not understand why patients responded so well to the therapy,’ said Noel de Miranda, an associate professor at the LUMC Department of Pathology.
Backup in our immune system
Research on cells from patients treated at the NKI has now shown that γδ T cells – a lesser-known specialised immune type of cell – are capable of detecting cancers that are invisible to conventional T cells. ‘This shows that there is a backup system in our immune system,’ said De Miranda. ‘When the main way of recognising tumour cells does not work, we have a second line of defence. Our findings could eventually lead to new treatments for “invisible” tumours with γδ T cells.’
New immunotherapies
‘We are only beginning to unlock the tremendous potential of γδ T cells for the development of novel cancer immunotherapies,’ said Emile Voest, Professor of Medical Oncology, group leader at the NKI and researchers at the Oncode Institute. ‘We have a better understanding of how these immune cells work in cancer patients’ bodies and how we can use them to develop novel immunotherapies. They will be particularly important for treating cancers that cannot be eliminated by conventional T cells.’
The research is funded by Oncode Institute and the European Research Council.