Although the tumor of only one of two responders contained melanoma cells with increased levels of fucosylated HLA-DRB1 compared with those of the non-responders (Fig. 7b(iii)), this trend mirrored that of intratumoral CD4+ T cell counts (Fig. 7b(iv)), consistent with the role for fucosylated HLA-DRB1 in CD4+ T cell-mediated tumor suppression. Here, HLA-DRB1 is linked to melanoma.