PDCD1 and cancer: This might be caused by the toxicity of the anti-PD-1 antibodies as what observed in cancer patients with immune-related adverse events (irAE).22 Previous work reported that pro-inflammatory bacteria belonging to the family Desulfovibrionaceae were more prevalent in feces from patients with renal cancer.23 Concomitantly, the frequency of uncultured bacteria from the genus of Desulfovibrionaceae was significantly reduced upon PD-1 blockade alone or in combination with CBM588 when compared to what observed in control mice (Figure 3a, b).