Figure 3.

The gut microbiota modulates the response to PD-1 blockade therapy. (A) The enrichment of fecal microbiota with Akkermansia muciniphila, Faecalibacterium spp and Bifidobacterium spp correlates with a positive response to PD-1 immune-checkpoint blockade in patients with various types of tumors. (B) A fecal microbiota transplantation from responders into tumor-bearing mice correlates with increased antitumor CD8+ T cells in the tumor and improved response to anti–PD-1 therapy. (C) On the other hand, the higher abundance of Bacteroidales correlates with a deficient response to PD-1 blockade therapy in humans. (D) Mice receiving FMT from non-responders show poor anti-tumor response to anti–PD-1 therapy, and tumors show a higher density of immunosuppressive CD4+ T_reg cells.