Magnesium Has Role in Mobilizing T Cells

Researchers from the University of Basel and University Hospital Basel have found that magnesium levels in the blood are vital for proper immune functioning, including against cancer.

While previous work has shown that mice fed a low-magnesium showed impaired immune response to the flu virus and a faster spread of cancerous growths, the new study was the first to suggest a mechanism by which magnesium impacts immune response.

Led by Professor Christoph Hess, a research group lead within the University of Basel’s Department of Biomedicine, the team confirmed that T cells can only eliminate abnormal or infected cells efficiently when in a magnesium-rich environment. They traced this specifically to a surface protein on T cells called LFA-1, which acts as a docking site and plays a role in T-cell activation. “[I]n the inactive state, this docking site is in a bent conformation and thus cannot efficiently bind to infected or abnormal cells,” Hess says. “This is where magnesium comes into play. If magnesium is present in sufficient quantities in the vicinity of the T cells, it binds to LFA-1 and ensures that it remains in an extended—and therefore active—position.”

The findings are significant for modern cancer immunotherapies, which mobilize the immune system—and cytotoxic T cells in particular—against cancer cells. In experimental models, the researchers were able to show that the immune response of T cells against cancer cells was strengthened by an increase in the local magnesium concentration in tumors. Further analysis by Hess’s lab showed that immunotherapies were less effective in patients with insufficient levels of magnesium in their blood.

“In order to verify this observation clinically, we’re now looking for ways to increase the concentration of magnesium in tumors in a targeted manner,” Hess adds. 

The work, “Magnesium sensing via LFA-1 regulates CD8+ T cell effector function,” is available online in Cell.