Perturbed mononuclear phagocyte system in severely burned and septic patients

Burn is one of the most common and devastating forms of trauma. Major burn injury disturbs the immune system, resulting in marked alterations in bone marrow hematopoiesis and a progressive suppression of the immune response, which are thought to contribute to increased susceptibility to secondary infections and the development of sepsis. Immunosuppression in severely burned and septic patients leads to high morbidity and mortality in these patients. Mononuclear Phagocytes System (MPS) is a critical component of the innate immune response and play key roles in burn immunity. These phagocytes are the first cellular responders to severe burn injury after acute disruption of the skin barrier. They are not only able to internalize and digest bacteria and dead cells and scavenge toxic compounds produced by metabolism, but also able to initiate an adaptive immune response. Severe burn and sepsis profoundly inhibit the functions of DC, monocyte and macrophage. Adoptive transfer of MPS or stem cells to severely burned and septic patients that aim to restore MPS function is promising. A better understanding of the roles played by MPS in the pathophysiology of severe burn and sepsis will guarantee a more rational and effective immunotherapy of severely burned and septic patients.