GPT and neoplasm: To evaluate the impact of VLA-4 levels on T cell trafficking to tumor, we again used IL-7 to generate an ALT consisting of CD4+ and CD8+ T cells that had increased VLA-4 expression compared with baseline levels seen when expanding with IL-2 (VLA-4Hi or VLA-4Lo ALT, pooled ALT expression shown in Supplemental Figure 4B).