A mouse serum two-dimensional gel map: Application to profiling burn injury and infection

With the importance of mouse as a model to study human diseases and the human and rat plasma/serum two-dimensional (2-D) maps being extensively annotated, this study was aimed at constructing a detailed mouse serum 2-D map. Serum proteins from two different inbred strains of mice (BALB/cJ and C57BL/6J) and mice subjected to two different inflammatory stimuli (20% burn injury and lipopolysaccharide (LPS) injection) were separated on overlapping gels covering pH 3-8 and stained with SYPRO Ruby dye. The tryptic peptides from the resolved spots were analyzed by mass spectrometry, leading to the identification of 38 different gene products. With the exception of major urinary proteins found in abundance in male C57BL/6J mice, little strain difference of the mouse serum 2-D was observed. Many proteins detected in the mouse serum 2-D map were not reported in human or rat serum 2-D maps including epidermal growth factor receptor. Three major murine acute-phase proteins (APPs), haptoglobin, serum amyloid A, and serum amyloid P, were highly induced by both inflammatory stimuli. Image analysis shows that the variations of APPs between these two inflammatory models were not uniform although LPS (100 mug/animal) in general was more effective than 20% burn injury in inducing APPs. Serum amyloid A, much more sensitive to endotoxin than burn injury, may represent a sensitive marker to differentiate these two different inflammatory states.