Researchers at Cardiff University have discovered a “T cell” found in human blood that recognizes and kills many types of cancer while ignoring healthy cells. Researchers suggest the cell could be used to develop a “one size fits all” cancer treatment.
T-cell therapies for cancer – where immune cells are removed, modified, and returned to the patient’s blood to find and destroy cancer cells – are the latest paradigm in cancer treatments. The most used is the CAR-T and is personalized for each patient. However, it targets only a limited number of cancers and has not succeeded in solid tumors, which constitute the majority of cancers.
But scientists have discovered T cells equipped with a new type of T cell receptor (TCR) that can distinguish healthy cells from diseased cells – only killing cancer cells, reports Metro UK.
Professor Andrew Sewell, lead author of the Cardiff University School of Medicine study, said that it was “very unusual” to find a TCR with such specificity against cancer, which opened the prospect of universal cancer therapy.
* He added: “We hope this new TCR can provide us with a different path to target and destroy a wide range of cancers in all individuals.”
“Current TCR therapies can only be used in a minority of patients with a minority of cancers.
“Targeting cancer with MR1-restricted T cells is an exciting new frontier – it opens up the prospect of ‘unique’ cancer treatment; a single type of T cell that may be able to kill many types of cancer in the population.
“Before, no one thought it could be possible.”
Conventional T cells scan the surface of other cells to find abnormalities and remove cancer cells, but ignore cells that contain only “normal” proteins. Scanning recognizes small parts of cellular proteins that are linked to cell surface molecules called human leukocyte antigen (HLA), allowing killer T cells to see what’s going on inside cells by scanning their surface.
But the study, published in Nature Immunology, describes a single TCR that can recognize many types of cancer via a single HLA-like molecule called MR1. Unlike HLA, MR1 does not vary in the human population, which means that it is a new and extremely attractive target for immunotherapy.
In the laboratory, T cells with the new TCR have been shown to kill cancer cells in the lung, skin, blood, colon, breast, bones, prostate, ovaries, kidneys and cervix of the uterus, while ignoring healthy cells.
To test the therapeutic potential of these cells in vivo, the researchers injected T cells capable of recognizing MR1 in mice carrying human cancer and having a human immune system.
Scientists say this has shown encouraging cancer elimination, comparable to CAR-T therapy now approved by the NHS in a similar animal model.
They were also able to demonstrate that the T cells of melanoma patients modified to express this new TCR could destroy not only the patient’s own cancer cells, but also the cancer cells of other patients in the laboratory, regardless of the HLA type of the patient. patient.
Researchers are currently experimenting to determine the precise molecular mechanism by which the new TCR distinguishes between healthy cells and cancer. They hope to test the new approach in patients by the end of the year