Table 1 Regulation of intestinal microbiota in cancer immunotherapy

Bifidobacteria

Promoting maturation of DCs

Activating lymphocytes

Upregulating IFN-γ and increasing pro-inflammatory cytokine

Initiating the proliferation of tumor-specific CD8⁺ T cells

Enhancing PD-1 blockade

B. fragilis

Activating Th1 cells

Promoting Tregs proliferation

Promoting maturation of DCs

Enhancing CTLA-4 blockade

A. muciniphila

Increasing CXCR3⁺CCR9⁺CD4⁺ T cells

Enhancing PD-1 blockade

Escherichia

Clostridium

Inducing the differentiation of Tregs and inhibiting inflammation

Enhancing CTLA-4 blockade

Faecalibacterium

Promoting the proliferation of CD4⁺ or CD8⁺ T cells

Promoting the production of Tregs and upregulating the expression of ICOS

Enhancing PD-1 blockade

Enhancing CTLA-4 blockade

Bacteroides

Upregulating the system’s MDSC and Tregs

Causing a systemic inflammatory response through the TLR-NF inflammatory pathway

Impeding PD-1 blockade

Impeding CTLA-4 blockade

microbial-derived SCFAs

Promoting the differentiation of Tregs

Enhancing CTLA-4 blockade