Fighting Liver Metastasis by Activating MAIT Cells.

In this issue, Ruf and colleagues show that antigen stimulation of mucosal-associated invariant T (MAIT) cells in the presence of the TLR9 ligand CpG decreases intrahepatic tumor growth, suggesting that MAIT cells could be used as an antitumor tool.See related article by Ruf et al., p. 1024 (3).