PD-1hi Identifies a Novel Regulatory B-cell Population in Human Hepatoma That Promotes Disease Progression

We identify a novel protumorigenic PD-1(hi) B-cell subset in human HCC that exhibits a phenotype distinct from that of peripheral regulatory B cells. TLR4-mediated BCL6 upregulation is critical for induction of PD-1(hi) B cells, which operate via IL10-dependent pathways upon interacting with PD-L1 to cause T-cell dysfunction and foster disease progression. Cancer Discov; 6(5); 546-59.