The study published on Wednesday in the journal Science Translational Medicine showed that a specific subtype of gamma delta T cells was linked to remission in patients with triple negative breast cancer, a hard-to-treat type of breast cancer.
Previously, gamma delta T cells have been found in the human gut and skin, and this is the first time they have been clearly characterised in human breast tissue, according to the study.
Researchers from the Francis Crick Institute, King's College London and other institutions examined the link between those cells and survival rates for a group of 11 women with triple negative breast cancer.
Those cells express certain receptors on their surface and respond directly to stress signals that commonly arise as a result of infection or cancer. Activated by a stress signal, those cells can kill damaged or tumor cells, according to the study.
By analyzing tumor samples from breast cancer patients, the researchers found that patients with higher numbers of those immune cells in their tumor were significantly more likely to survive than those with low numbers.
Of the five patients who went into remission and survived their cancer, all had relatively high numbers of the cells in their tumors. Whereas, of the six patients who died within two years, only one had high numbers of those cells, according to the study.
"It could mean that in the future we're able to improve a patient's chance of survival by either artificially activating more of these cells to fight the tumor cells or we could transfer cells from a donor," said the paper's coauthor Wu Yin, a clinician at Guy's and St Thomas' Hospital and University College Hospital.