Stenotrophomonas-maltophilia inhibits host cellular immunity by activating PD-1/PD-L1 signaling pathway to induce T-cell exhaustion

•We first described the S.maltophilia immunosuppressive effect on T cells and it is meaningful for immunosuppressed patients or co-infections.•T cells stimulated by S.maltophilia with CD4 and CD8 degraded via PD-1/PD-L1 pathway, which led to the massive apoptosis of T cells.•T cells were stimulated by S. maltophilia to secrete IFN-γ. Blocking the PD-1/PD-L1 pathway, apoptosis was suppressed.•S.maltophilia down-regulates host immunity by inhibiting immune cells.