FIG 4.

Trained immunity decreases immunosuppression by inducing an effective innate immune response. The “trained” innate immune system becomes activated by the extensive release of damage-associated molecular patterns (DAMPs) from damaged tissue. In addition, the relatively small release of pathogen-associated molecular patterns (PAMPs) from invading pathogens contributes to eliciting an immune response. Upon recognition of DAMPs and PAMPs, “trained” innate immune cells show an increased responsiveness, thereby resulting in an effective clearance of pathogens and damaged tissue. This results in a low concentration of PAMPs and DAMPs in the surgical wound, thereby preventing excessive inflammation and severe immunosuppression.