Isolation and characterization of a cutaneous lipoprotein with lethal effects produced by thermal energy in mouse skin

Curbing inflammation in burn patients

Patients who suffer from severe burns develop metabolic imbalances and systemic inflammatory response syndrome (SIRS) which can result in multiple organ failure and death. Research aimed at reducing the inflammatory process has yielded new insight into burn injury therapies. In this review, we discuss strategies used to curb inflammation in burn injuries and note that further studies with high quality evidence are necessary.

Damage limitation in burn surgery

Burn injury differs from other types of trauma in the apparent lack of urgency for treatment. We argue that in order to limit physiological damage and the development of multi-organ failure, management of the burn wound must be immediate and aggressive. Supportive fluid treatment should be judicious in order to prevent excessive oedema causing wound extension. Some potential strategies utilising oral fluid resuscitation are discussed, and potential pharmacological interventions. When associated with other trauma, major burn injury has a detrimental effect on morbidity and mortality, and surgical management of both aspects of a patient's injuries are altered.

Skin toxicity induced by wet heat

Pieces of human skin from the skin bank were heated in an autoclave for 1 or 5 min at temperatures 80, 90, 100, 110 and 135 degrees C. The pieces were then homogenized and the homogenates were injected intraperitoneally into groups of mice. The amount injected was either a quantity equivalent to 50 or 75% of the mouse body surface area. Fourteen separate experiments were carried out, each one with a variety of temperatures. Mortality in the groups of mice was recorded by the 8th day. Control mice received homogenates of skin heated to no more that 38 degrees C and out of a total of 104 control mice there were only 4 deaths. In contrast homogenates of skin heated to 135 degrees C killed from 80 to 100% of the mice in different groups, averaging 92%. Skin heated to 110 degrees C killed from 33 to 90% of the mice in different groups, averaging 63%. Skin heated to 100 degrees C killed from 0 to 80% of the mice in different groups, averaging 33%. Temperatures of 80 and 90 degrees C killed no more than 10% of the mice in any group, averaging less than 3%. One minute of heating seemed to be sufficient to induce the toxic effect in the skin. These findings indicated that wet heat application to skin was capable of inducing toxicity in a fashion similar to that demonstrated many years ago with hotter dry temperatures applied to skin for 15s. That application was shown to induce polymerization of skin cell membrane lipid proteins rendering them toxic. In this study, increasing toxicity appeared similarly to depend on the quantity of wet heat input as illustrated by the range of increasing temperatures. The relatively lower temperatures of scalding versus flame burns can accomplish similar dangerous effects; it is simply a quantitative matter of heat input.

Comparison of endotoxins and cutaneous burn toxin as immunosuppressants

Endotoxins of E. coli, S. typhosa and Ps. aeruginosa were injected i.p. into mice a few days before administration of the antigen sheep erythrocytes (SE). Antibody-forming cells (AFC) to SE were later enumerated in relation to dose of endotoxin given. In comparison a toxic lipid protein isolated from burned skin (cutaneous burn toxin or CBT) was similarly applied and found to be more inhibitory of the immune response than any of the three endotoxins. Considering the 50 per cent inhibitory doses on a molar basis CBT was found to be 1000 fold more immunosuppressive than the most inhibitory endotoxin. As the immune suppression which follows severe thermal injury involves failure of interleukin 2 (IL2) function, as a critical index of survival, the CBT was tested for its effects on the culture of a human IL2-dependent cell line in the presence of IL2. CBT inhibited the growth of these cells, however, endotoxin had no effect on their proliferation. Thus CBT, which arises by a thermally induced polymerization of skin lipid protein, is specific to burn injury and has a direct inhibitory effect on the immune response.