Using a CLP model of murine sepsis, a recent study by Lou et al. showed increased LAG-3 expression not only on CD4 and CD8 T cells, but also on B cells, regulatory T cells, and dendritic cells, and treatment with anti-LAG-3 antibody improved T cell function, bacterial clearance and survival after sepsis (44). The gene discussed is LAG3; the disease is Sepsis.