Because our previous work indicated that TCR2C encountered cognate antigen in the spleen very early after leukemia challenge (Kline et al., 2018), TCR2C expansion and CD44 upregulation were assessed 2 days following i.v. C1498.SIY cell challenge (3 days following TCR2C adoptive transfer) in various organs, including the spleen, liver, liver-dLNs (celiac and portal), skin-dLNs, bone marrow, and blood. Here, CD44 is linked to leukemia.