Objective: Proteomic analysis could improve our understanding of the mechanisms and consequences of myeloproliferation. Healthy subjects treated with granulocyte colony-stimulating factor (G-CSF) were used as a model of myeloproliferation.
Methods: Levels of 80 soluble factors were measured by enzyme-linked immunosorbent assay before and after 5 days of G-CSF. Both serum and plasma levels were measured to generate a comprehensive profile and determine whether serum or plasma best portrays biological and physiological changes.
Results: Comparison of samples collected prior to G-CSF demonstrated that 44 factors differed between serum and plasma. Concentrations of several growth factors and chemokines were greater in serum than in plasma, while the opposite was true for several interleukins. Following G-CSF serum levels of 14 factors and plasma levels of 15 factors changed. Eleven increased in both serum and plasma, including cell adhesion molecules (vascular cell adhesion molecule-1, E-selectin, and L-selectin), matrix metalloproteases (MMP-1, -8, and -13), cytokine receptors (tumor necrosis factor receptor 1 and 2, and interleukin-2 receptor), the acute phase reactant, serum amyloid A, and a growth factor, hepatocyte growth factor.
Conclusion: Some protein levels differ markedly in serum and plasma. Myeloproliferation is associated with changes in the levels of several proteases, adhesion molecules, and cytokines.