Antibody-negative ALE and CNS-DLBCL patients showed similar increases in activated CD4+ Tc in PB and CSF as well as CD8+ Tc in PB, although the percentages were even higher in CNS-DLBCL than in antibody-negative ALE (Fig. 2B, F, H, R). Here, CD4 is linked to diffuse large B-cell lymphoma.