PRF1 and diffuse large B-cell lymphoma: Levels of perforin were higher in CD8+ T cells from patients with DLBCL cultured with SU-DHL6 or OCI-LY3 cells after treatment with anti-LAG-3, anti-PD-1, or a combination of the two, relative to the PBS control group, and levels were highest after combination therapy (Figures 8A, C).