In both the spleen and tumor, the frequency of CX3CR1+ in wild-type Pmel-1 CD8+ T cells was comparable to that of DTR-expressing cells in Pmel-1 Cd2-cre/Cx3cr1DTR/DTR CD8+ T cells, indicating that the presence of differentiated antigen-specific CD8+ T cells within the tumor is independent of the presence of CX3CR1 (Fig. 4C). Here, CD2 is linked to neoplasm.