| Intestinal absorptive function |
Lactulose |
Disaccharide, indicator of gut barrier disruption |
Administered orally and measured in urine |
|
Mannitol |
Monosaccharide, indicator of gut absorptive surface |
Administered orally and measured in urine |
|
Lactulose:Mannitol ratio (%L and %M) |
Indicator of barrier disruption per surface area |
Administered orally and measured in urine |
|
Rhamnose |
Monosaccharide, indicator of absorptive surface |
Administered orally and measured in urine |
|
D-xylose |
Monosaccharide, indicator of absorptive surface |
Administered orally and measured in urine |
|
GMCSF antibody |
Granulocyte macrophage colony stimulating factor autoantibody |
Plasma |
| Intestinal barrier function |
alpha-1-antitrypsin |
Plasma protease inhibitor, indicator of relatively severe gut barrier disruption |
Stool |
|
Claudin-2 |
Tight junction peptide reflecting increased permeability |
Intestinal tissue staining |
|
Claudin-15 |
A marker of “healthy” gut absorptive and barrier function |
Urine |
| Translocation |
LPS |
Lipopolysaccharide |
Plasma |
|
IgA and IgG anti-LPS |
Antibody produced against lipopolysaccharide |
Plasma |
|
IgA and IgG anti-FliC |
Antibody produced against bacterial FliC (flagellin) |
Plasma |
|
Zonulin |
Tight junction peptide regulator of gut permeability (haptoglobin) |
Plasma |
|
TJP1 |
Tight junction protein gene encoding for ZO-1 |
Intestinal biopsy, tissue DNA |
| Intestinal inflammation |
MPO |
Myeloperoxidase, a neutrophil granule component |
Stool |
|
Calprotectin |
Neutrophil marker |
Plasma; stool |
|
Neopterin |
Monocyte/macrophage marker of immune activation (GTP metabolite) |
Stool |
|
Lactoferrin |
Neutrophil granule component |
Stool |
|
Lipocalin |
Protein in neutrophils and epithelial cells |
Stool |
|
Reg 1A |
Regenerating islet-derived protein-α |
|
|
Reg1β |
Marker of epithelial repair |
Stool |
|
I-FABP |
Intestinal fatty acid binding protein |
Plasma |
|
Fecal S100A12 |
Calcium (and zinc, copper)-binding protein regulator of inflammatory signaling |
Stool |
| Systemic inflammation |
AGP |
Acid glycoprotein, a hepatic “acute phase reaction” product |
Plasma |
|
IL-1β |
Interleukin-1β, inflammatory cytokine produced by monocytes and macrophages |
Plasma |
|
IL-4 |
Th2 cytokine |
Plasma |
|
IL-5 |
Th2 and mast cell cytokine |
Plasma |
|
IL-6 |
Pro or anti-inflammatory T cell or macrophage cytokine or myokine |
Plasma |
|
IL-7 |
Lymphokine stimulator of stem cell differentiation into B, T or NK lymphoid cells |
Plasma |
|
IL-10 |
Anti-inflammatory STAT3 inducer cytokine |
Plasma |
|
TNFα |
Proinflammatory cytokine |
Plasma |
|
MIP1β |
Macrophage inflammatory protein 1β (CCL4) |
Plasma |
|
Ferritin |
Iron binding protein reflecting iron stores |
Serum |
|
Hepcidin |
Inflammation driven inhibitor of iron exporter ferroportin, thus blocker of iron uptake or release into the circulation; hence anemia of chronic inflammation |
Plasma |
|
C-reactive Protein (CRP) |
An acute phase reactant (APR) |
Plasma |
|
hsCRP |
High sensitivity C-reactive protein (APR) |
Plasma |
|
sCD14 |
Soluble CD14; shed by activated monocytes, binds LPS |
Plasma |
|
EndoCAb |
Antibody produced against bacterial lipopolysaccharide |
Plasma |
|
Serum amyloid A |
Acute phase reactant driver of inflammation |
Plasma |
|
LBP |
LPS binding protein |
Plasma |
| Metabolites/ Growth markers |
Tryptophan |
Essential amino acid for protein synthesis and growth as well as the neurotransmitter, serotonin |
Plasma |
|
Kynurenine |
Tryptophan metabolite via IDO, potentially driven by inflammation |
Plasma |
|
K:T ratio |
Kynurenine:tryptophan ratio |
Plasma |
|
Citrulline |
Key amino acid for intestinal repair |
Plasma |
|
IGFBP-3 |
Insulin-like growth factor binding protein-3 |
Plasma |
|
IGF-1 |
Insulin-like growth factor 1 |
Plasma |
|
Activin |
Growth regulation factor |
Plasma |
