Table 1.

Comparison of human biomarkers in literature before and after the Human Microbiome Project

Proposed Mechanism	BEFORE	AFTER
Acute phase reactants/inflammation	CRP (85, 86)	CRP (78, 87–89) IaIps (81)
	Cytokines: IL-2, IL-6, IL-8, IL-1β, TNFα IL-1RA, IL-4, IL-10 (34, 36, 37, 90)	Cytokines: IL-8, TGF-β IL-1RA, IL-1β (38, 51, 61, 67, 91)
	PAF (92, 93)
Tissue injury/protection	Calprotectin (47)	Calprotectin (94–97)
	I-FABP (44, 98, 99) Serum SAA and apolipoprotein-CII (ApoSAA score) (62) Urine I-FABP, claudin 3, and fecal calprotectin (41)	Combination markers: Urine IFABP, SAA and fecal calprotectin (49) L-FABP, I-FABP, and TFF3 (LIT score) (52) EpCAM/MMp7 ratio (78) Urine protein panel (64, 65) Serum protein panel (63)
	Amino acids arginine and glutamine (100–103)	Non-protein amino acid citrulline (104, 105) Heat shock, angiogenesis, cytoskeleton, metabolism proteins (106)
Lipid metabolism/signaling		C21 steroid, linoleate, leukotriene and prostaglandin metabolism (15) Acylcarnitines (70)
Coagulation/Vascular injury		Fibrinogen-γ dimers (64–66)
Intestinal microbiota	Theoretical (11, 33)	Community structure, reviewed in (107, 108) Metabolic signature Alanine:histidine ratio (13) Volatile organic compounds (31, 32)

Abbreviations: CRP C-reactive protein; IL interleukin; MMp7 matrix metalloproteinase-7; EpCAM epithelial cell adhesion molecule; IaIp inter-alpha inhibitor proteins; IL-1RA interleukin1 receptor antagonist; TNFα tumor necrosis factor; TGF-β transforming growth factor beta; PAF platelet-activating factor; I-FABP intestinal fatty acid binding protein; L-FABP liver fatty acid binding protein; SAA serum amyloid A; TTF trefoil factor 3.