Scientists from Cardiff University have discovered a superior form of killer T-cell in patients who have successfully cleared end stage solid cancer.
Published today in the journal Cell, the researchers discovered that dominant, successful killer T-cells were capable of recognising multiple different cancer-associated targets at the same time.
Until now, scientists believed that individual killer T-cells only saw a single target on cancer cells.
The 'multipronged' cells found by the team differ to those previously studied and have superior properties, allowing them to attack cancer in several ways simultaneously.
What did the Cardiff research team do?
The researchers looked at patients with late stage solid cancer who were given TIL (Tumour-infiltrating lymphocyte) therapy at the National Center for Cancer Immune Therapy in Herlev, Denmark (CCIT-DK). TIL therapy takes white blood cells (lymphocytes) from a patient's tumour, grows them in large numbers in a laboratory, and gives them back to the patient to help the immune system kill the cancer cells. CCIT-DK has pioneered TIL therapy in Europe.
In a phase I/II clinical trial that ran over the last decade, 31 patients were given TIL therapy. All of the TIL cells given to these patients were T-cells.
The team then waited to see which of these patients cleared their cancer and focused on them.
Then, they challenged the blood cells from these patients with stored samples of the patient's own tumour cells to see which T-cells responded.
They found that the cancer survivors still showed very strong killer T-cell responses to their own cancer over a year after they had cleared it.
The researchers then went on to identify how these killer T-cells were distinguishing cancer cells from normal cells.
