Table 3.

Functions of top protein candidates identified by iTRAQ

Protein	Function
Complement component 4A	Part of the complement system; plays an important role in the pathogenesis of  alcoholic liver fibrosis
Inter-alpha-trypsin inhibitor heavy chain H4	Suggested fibrosis biomarker
Vitamin D-binding protein	Actin scavenging, fatty acid transport, macrophage activation, and chemotaxis
Serine (or cysteine) proteinase inhibitor, clade C  (antithrombin), member 1	Neuronal cell death, angiogenesis
Lumican	Regulates collagen fibril assembly
Insulin-like growth factor binding protein	Binds IGF and modulators of IGF’s availability and activity. Important for cell  growth
Serine (or cysteine) proteinase inhibitor, clade A,  member 7	Thyroid binding globulin. Important for growth and metabolism
Complement component 8	Part of the complement system; plays an important role in the pathogenesis of  alcoholic liver fibrosis
Pro-platelet basic protein	Response to inflammation, may be involved in coagulation
Cell adhesion molecule homology to L1CAM	L1 cell adhesion molecules are related to organization of neurons
Complement component 1, q subcomponent, gamma  polypeptide	Part of the complement system; plays an important role in the pathogenesis of  alcoholic liver fibrosis
Coagulation factor IX	Important for hemostasis
PTK2B protein tyrosine kinase 2 beta	Regulator of keratinocyte differentiation, cancer cell growth