The role of neutrophil myeloperoxidase in the development of inflammation after thermal skin burns

In the blood of children (n=16) with large thermal skin burns (> 20% of total body surface), luminol-dependent chemiluminescence (CL) of neutrophils stimulated with phorbol-12-myristate-13-acetate (PMA) and myeloperoxidase (MPO) activity in neutrophils and plasma were assayed in the early period (1-7 post-burn days). PMA-stimulated neutrophils in thermally injured patients produced higher CL than those in a reference group of healthy children (n=24), p<0.01. MPO activity was elevated in neutrophils and plasma in 40% and 57% of patients' blood samples, respectively. The albumin fraction isolated from plasma of burned patients enhanced the PMA-stimulated CL response of blood samples from healthy volunteer. Our results suggest that the acute inflammatory response induced by thermal injury involves activation of neutrophils and is accompanied by MPO release into the plasma. MPO-mediated modification of serum albumin induces its capacity to prime neutrophils and thus to enhance further inflammatory reaction.