CD4 and neoplasm: Fundamentally, intra-tumoural recruitment is not a ‘one-chemokine–one-receptor task’ but rather a complex interaction of multiple receptors and chemokines within a tumour-bearing mouse, and as such recruitment-blockade cannot be achieved by targeting a particular chemokine nor can a particular chemokine axis be identified that would serve to block Foxp3+ but not Foxp3− CD4+ T cells.