Breakthrough research from an international team of scientists has uncovered a new type of immune cell with the ability to target and kill most kinds of cancer cells. The discovery was previously thought to be impossible and, although it is still untested in human subjects, it offers the potential for revolutionizing immunotherapy as a possible universal cancer treatment.

One of the most groundbreaking recent advances in cancer treatment has been the development of CAR-T immunotherapy. This highly personalized treatment involves harvesting a patient’s immune T cells and reprogramming them to target specific proteins found on the patient’s cancer cells.

In 2017 the FDA approved the first treatment of this type for young patients with a rare kind of blood and bone marrow cancer. However, the therapy is expensive, time-consuming to produce, and not without the risk of severe side effects.

The big limitation faced by researchers working on CAR-T therapies is that there isn’t one universal T-cell receptor (TCR) that can target different kinds of cancers in all patients. In fact, it was generally thought this kind of universal cancer-targeting TCR simply didn’t exist.

A new study, published in the prestigious journal Nature Immunology, suggests a universal TCR does exist, and it has been found. The research describes the discovery of an immune T-cell that displays a novel receptor that seems to have the ability to target and kill a broad variety of human cancer cell types while leaving healthy cells alone.

The newly discovered T-cell is thought to be able to distinguish cancer cells from healthy ones by homing in on a surface molecule called MR1. While this molecule is present on almost all cells in the human body, the researchers suspect it presents differently on cancer cells, allowing for a single TCR to be able to effectively target a broad variety of tumors.

An outline describing how the newly discovered T-cell targets and kills cancer cells Cardiff University

“Current TCR-based therapies can only be used in a minority of patients with a minority of cancers,” says lead author on the new study, Andrew Sewell. “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.”

It is still incredibly early days for the research with this study only showing the new T-cells as effective in cellular lab tests and initial animal studies. However, the early animal tests are encouraging, and Sewell suggests human trials could commence very soon if further safety tests are successful.

“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,” says Sewell.

Cancer experts not affiliated with the new research are cautiously optimistic, noting this breakthrough could lead to a novel universal treatment. Astero Klampatsa, from London’s Institute of Cancer Research, says more work is needed before we get too excited, but the new study is certainly promising.

“The new findings are at a very early stage, but they’re an exciting step in the right direction, and brings us one step closer to ‘off-the-shelf’ cell-based immunotherapy,” says Klampatsa.

Awen Gallimore, a Cardiff University researcher who did not work on this particular study, agrees the discovery could be truly transformative, paving the way for a universal form of cancer immunotherapy previously considered to be impossible.

“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,” says Gallimore. “This is truly exciting and potentially a great step forward for the accessibility of cancer immunotherapy.”

The new study was published in the journal Nature Immunotherapy.

Source: Cardiff University