The extent of thermal injury affects fractions of mononuclear cells

BackgroundThe mononuclear cell (MNC) fraction contains a variety of cell types, including stem cells such as endothelial progenitor cells (EPCs). EPC can rapidly revascularise ischaemic areas, but their role in burns is unclear.AimThis study investigates how thermal injury to the skin might influence mononuclear cells, CD34+ cells and circulating EPC.MethodsThe study group comprised 17 people with burns and 17 age-matched controls. Blood samples were collected at five different time points during the first 5 days of hospitalisation. Clinical parameters and scores were documented as well as cell counts for MNC, CD34+ cells and EPC. Counts were quantified by fluorescence-activated cell sorting. Serum was tested for vascular endothelial growth factor VEGF165 by ELISA.ResultsAll cell populations displayed significant, differing changes in counts and percentages after burn. These effects varied markedly over time and expressed different patterns if clinical scores were subjected to significance testing. EPC counts were significantly lowered in cases with fatal outcome.ConclusionBurn affects the numbers of circulating MNC, CD34+ and EPC. These time-dependent changes imply involvement of these cell groups in the trauma. EPC counts seem to be a predictive factor for outcome of cases of severe burn.