ACUTE SKIN INJURY RELEASES NEUTROPHIL CHEMOATTRACTANTS

Background. Progressive or ongoing skin necrosis after traumatic injur y is well know. Experimental evidence has associated these events with neutrophil activation and secondary oxidant injury. To determine the mechanism by with neutrophils migrate to a site of injury, cytokine re lease from injured skin was measured. Methods. Twenty-five skin biopsy specimens of acute partial thickness skin injuries were compared with uninjured skin of the same patient. Conditioned medium from explanted skin was assayed for tumor necrosis factor (TNF), interleukin-6 (IL-6 ), and IL-8. Results. Acute skin injury resulted in a significant rele ase of IL-8 but not IL-6 or TNF. In eight patients gradient cytokine r elease was found; IL-8 levels for partial thickness burn were 26.4 ng/ ml, for unburned skin adjacent to the burn were 2.1 ng/ml, and for dis tal normal skin were 0.2 ng/ml. Conclusions. IL-8 is released from acu tely injured skin; IL-6 and TNF are not. This selective release sugges ts a mechanism whereby neutrophils are recruited into injured tissue. These neutrophils might then induce further injury, increasing the ext ent of posttraumatic tissue loss.