To test the therapeutic potential of these cells in vivo, the researchers injected T-cells able to recognize MR1 into mice bearing human cancer and with a human immune system. This showed “encouraging” cancer-clearing results which the researchers said was comparable to the now NHS-approved CAR-T therapy in a similar animal model. T-cell recognition of multiple cancers with and without the MR1 gene and other methods were used to confirm the mechanism by which these cancers were being targeted and destroyed.The group were further able to show that T-cells of melanoma patients modified to express this new TCR could destroy not only the patient’s own cancer cells, but also other patients’ cancer cells in the laboratory, regardless of the patient’s HLA type.Professor Andrew Sewell, lead author on the study and an expert in T-cells from Cardiff University’s School of Medicine, said it was “highly unusual” to find a TCR with such broad cancer specificity and this raised the prospect of “universal” cancer therapy.“We hope this new TCR may provide us with a different route to target and destroy a wide range of cancers in all individuals,” he said.“Current TCR-based therapies can only be used in a minority of patients with a minority of cancers.“Cancer-targeting via MR1-restricted T-cells is an exciting new frontier - it raises the prospect of a ‘one-size-fits-all’ cancer treatment; a single type of T-cell that could be capable of destroying many different types of cancers across the population.“Previously nobody believed this could be possible.”Experiments are under way to determine the precise molecular mechanism by which the new TCR distinguishes between healthy cells and cancer.The researchers believe it may work by sensing changes in cellular metabolism which causes different metabolic intermediates to be presented at the cancer cell surface by MR1.The group hope to trial this new approach in patients towards the end of this year following further safety testing.Professor Sewell said a vital aspect of this ongoing safety testing was to further ensure killer T-cells modified with the new TCR recognize cancer cells only.“There are plenty of hurdles to overcome however if this testing is successful, then I would hope this new treatment could be in use in patients in a few years’ time,” he said.Professor Oliver Ottmann, Cardiff University’s Head of Haematology, whose department delivers CAR-T therapy, said: “This new type of T-cell therapy has enormous potential to overcome current limitations of CAR-T, which has been struggling to identify suitable and safe targets for more than a few cancer types.”Professor Awen Gallimore, of the University’s division of infection and immunity and cancer immunology lead for the Wales Cancer Research Centre, said: “If this transformative new finding holds up, it will lay the foundation for a ‘universal’ T-cell medicine, mitigating against the tremendous costs associated with the identification, generation and manufacture of personalized T-cells.“This is truly exciting and potentially a great step forward for the accessibility of cancer immunotherapy.”Crowther. (2020) Genome-wide CRISPR–Cas9 screening reveals ubiquitous T cell cancer targeting via the monomorphic MHC class I-related protein MR1.. DOI: https://doi.org/10.1038/s41590-019-0578-8This article has been republished from the following materials . Note: material may have been edited for length and content. For further information, please contact the cited source.