The objective of the proposed research is the definition of the perturbations of the immune response which follow traumatic injury and burns in humans. We are particularly concerned with mechanisms which underlie the immunological deficiencies found in these patients with the ultimate goal of developing therapeutic approaches for preventing or counteracting these potentially harmful abnormalities. We are specifically interested in deficiencies of cellular immunity acquired abnormalities of the alternative complement pathway and the role played by the tissue fibrinolytic system in the clinical manifestations of major trauma and burns.