Altered plasma proteome during an early phase of an experimental model of peritonitis-induced sepsis

Introduction

The pathophysiology and molecular mechanisms involved in sepsis are complex and poorly understood. We performed a proteomics study to characterize early host responses to sepsis as determined by altered plasma proteome in a porcine model of peritonitis-induced sepsis.

Methods

In seven instrumented and mechanically ventilated pigs, sepsis was induced by inoculating autologous faeces. Haemodynamics, oxygen exchange, inflammatory responses, oxidative and nitrosative stress, and other laboratory parameters were monitored. Plasma samples were obtained before and 12 hours after the induction of hyperdynamic sepsis. Plasma proteins were resolved by two-dimensional electrophoresis. Proteins that changed in abundance were identified by mass spectrometry (MS, quadrupole TOF/TOF MS and MS/MS).

Results

From approximately 1,500 protein spots in each gel, levels of 47 proteins spots were significantly altered in the septic plasma samples compared with corresponding baseline ones. MS identified 35 protein forms representing 22 unique proteins whose plasma levels were increased, whereas 12 forms of eight unique proteins were significantly decreased during sepsis.

Conclusion

We identified a set of plasma proteins with significantly altered levels during an early phase of sepsis in a porcine model of peritonitis-induced sepsis using a proteomics approach. Most of these altered proteins have important roles in the inflammatory response. Some findings are novel, and exploring their roles may lead to the identification of new therapeutic targets.