Table 4

Principal component analysis of serum biomarkers in ankylosing spondylitis patients at baseline

PC1

PC2

PC3

PC4

PC5

PC6

PC7

PC8

IL-15 (0.972)

IFNγ (0.955)

MMP-8 (0.849)

GM-CSF (0.913)

CXCL10 (-0.676)

MMP-2 (-0.700)

bFGF (0.744)

EGF (0.735)

IL-2 (0.970)

IL-12 (0.936)

MMP-9 (0.796)

IL-10 (0.813)

IL-13 (0.626)

MMP-3 (-0.759)

IL-1Ra (0.493)

CXCL8 (0.436)

MIP-1β (0.930)

IL-5 (0.842)

CXCL8 (0.527)

VEGF (0.437)

MCP-1 (0.425)

IFNα (0.916)

Eotaxin (0.760)

HGF (0.453)

IL-1β (0.877)

IL-2R (0.712)

TNFα (0.841)

IL-17 (0.633)

MIP-1α (0.812)

IL-4 (-0.565)

IL-7 (0.771)

IL-13 (0.525)

IL-6 (0.736)

MCP-1 (0.499)

MIG (0.722)

VEGF (-0.477)

IL-1Ra (0.680)

TNFα (0.408)

IL-17 (0.674)

IL-4 (0.673)

IL-2R (0.609)

GCSF (0.486)

HGF (0.462)

30.16%^a

17.61%^a

6.63%^a

6.03%^a

4.80%^a

3.90%^a

4.70%^a

4.44%^a

Biomarkers in each principal component are shown with factor loadings (brackets) after varimax rotation. bFGF, basic fibroblast growth factor; EGF, epidermal growth factor; G-CSF, granulocyte colony-stimulating factor; GM-CSF, granulocyte-macrophage colony-stimulating factor; HGF, hepatocyte growth factor; IL-1Ra, IL-1 receptor antagonist; MCP-1, monocyte chemotactic protein-1; MIG, monokine induced by gamma interferon; MIP-1, macrophage inflammatory protein-1; MMP, matrix metalloproteinase; PC, principal component; VEGF, vascular endothelial growth factor. ^aPercentage variance.

Mattey et al. Arthritis Research & Therapy 2012 14:R127   doi:10.1186/ar3857