Interleukin-10 gene transfer: prevention of multiple organ injury in a murine cecal ligation and puncture model of sepsis.

INTRODUCTION: The aim of this study was to determine the effect of immunoregulatory cytokine interleukin-10 (IL-10) gene therapy on multiple organ injury (MOI) induced by a cecal ligation and puncture (CLP) model of sepsis in mice.

METHODS: Male Balb/c mice subjected to CLP were treated with either an hIL-10-carrying vector or an empty control vector. We assessed the degree of lung, liver, and kidney tissue destruction biochemically by measuring myeloperoxidase (MPO) and malondialdehyde (MDA) activity. Histologic assessments were based on neutrophil infiltration in lung and liver tissue. IL-10 protein expression was examined immunohistochemically, and ultrastructural changes in the liver were studied by transmission electron microscopy. We analyzed the expression of tumor necrosis factor-alpha (TNFalpha) mRNA by reverse transcription polymerase chain reaction 3, 8, and 24 hours after CLP in all organs.

RESULTS: Organ damage was significantly reduced by hIL-10 gene transfer, which was associated at the tissue level with reduced MPO activity in the liver, lung, and kidney and decreased leukocyte sequestration and MDA formation in the lung. The liver MDA was not significantly higher in the hIL-10 gene therapy group than in the controls and seemed not to be affected by hIL-10 gene transfer. The reduced portal tract neutrophilic infiltration and preserved ultrastructure of the hepatocytes also showed that tissue function was not impaired. The lung and kidney TNFalpha mRNA expression was suppressed markedly in the hIL-10 gene therapy group, but liver TNFalpha mRNA expression varied over time.

CONCLUSIONS: These findings showed that IL-10 gene therapy significantly attenuated sepsis-induced MOI.