Publication in the renowned “Cell” journal with Bernese participation (Professor Maria Louisa Balmer): Magnesium is vital to the immune system—and the fight against cancer

Professor Maria Luisa Balmer of the Diabetes Center Berne, University Berne, and University Hospital Bern

Magnesium deficiency is linked to a variety of illnesses, such as infections and cancer. We know from previous studies that cancerous tumours spread more quickly in the bodies of mice when they are fed a diet that is low in magnesium. This low-magnesium diet also impairs their ability to fight off flu viruses. Until now, there has been little research into exactly how this vital mineral affects the immune system.

A team of researchers led by Professor Christoph Hess, from the University of Basel and University Hospital Basel, and University of Cambridge, in collaboration with University and University Hospital Bern, have discovered that T cells can only effectively eliminate abnormal or infected cells in a magnesium-rich environment. More specifically, magnesium contributes to the proper functioning of a T-cell surface protein called LFA-1.

LFA-1 functions as a binding site that plays a key role in the activation of T cells. “In the resting state, however, this binding site is in a closed position and therefore cannot efficiently bind infected or abnormal cells,” explained Christoph Hess. “That’s where magnesium comes in. If magnesium is present in sufficient quantities in the environment surrounding the T cells, magnesium binds to the LFA-1 protein and ensures that it remains in an open position, keeping the binding site active.”

As part of the research team, Professor Maria Luisa Balmer is delighted with what the team has achieved so far and adds:

“Many people associate the trace element magnesium primarily with its effects on muscle function. What this new study shows is that magnesium also regulates fundamental processes in immune cells, and that this regulation has a significant effect on how they function. This research is a prime example of how findings from basic research can lead to further investigations that may directly benefit patients and the wider population.”

Relevance to cancer patients

The fact that magnesium is essential for the function of T cells could have significant implications in terms of how modern immunotherapies are used to treat cancer. Immunotherapy aims to mobilise the immune system—and cytotoxic T cells in particular—against cancer cells. The researchers were able to use experimental models to demonstrate that increasing the local magnesium concentration in tumours enhanced the immune response of T cells against cancer cells.

“We are now looking for ways to specifically increase the concentration of magnesium in tumours so that we can test this observation in the clinical context,” said Christoph Hess. Further analyses carried out by the research team led by Hess and his colleague Dr Jonas Lötscher, the lead author of the study, demonstrate how promising such strategies can be. Using data from studies in cancer patients that have already been completed, the researchers were able to show that immunotherapies were less effective in patients who had low blood magnesium levels.

However, according to Lötscher, the data collected to date is not sufficient to answer the question of whether regular magnesium intake has an effect on the risk of cancer in general.

“Our next step will be to conduct prospective studies to test the clinical effect of magnesium as a catalyst in the immune system.”

Original publication
Jonas Lötscher et al.
Magnesium sensing via LFA-1 regulates CD8+ T cell effector function.
Cell (2022)
DOI: https://doi.org/10.1016/j.cell.2021.12.039