Biomarkers of Joint Damage in Osteoarthritis: Current Status and Future Directions

Table 2

List of biomarkers routinely used in the diagnosis and treatment of osteoarthritis and the studies of these markers in patients.

Biomarker name	Description	Evidence for role in OA	Sample type	Expression level in OA	References
Coll-2	Type-II collagen	Cartilage loss	S, SF	Upregulated	[28]
PIIANP	Type IIA collagen N-propeptide	Proanabolic agent of cartilage	S, SF	Downregulated	[32]
CPII	Type II procollagen carboxy propeptide	Destruction and loss of cartilage	S, SF	Downregulated	[34]
COMP	Cartilage oligomeric matrix protein	Cartilage loss	S, SF	Upregulated in an early stage, downregulated in late stage	[40]
HA	Hyaluronic acid	Immobility, cartilage loss, and stiffness in joints	S, SF	Downregulated	[46]
Aggrecan		Loss connectivity between chondrocyte-ECM	S, SF	Downregulated	[51]
FSTL1	Follistatin-like protein	Induces IFN-γ signaling pathway and stimulates proinflammatory factors	S, SF, U	Upregulated	[56]
IL-1	Interleukin -1	Promotes activation of chondrocyte osteoclasts.; Proinflammatory cytokines	S, SF	Upregulated	[68]
IL-6	Interleukin-6	Promotes neutrophil chemotaxis and proinflammatory cytokines	S,SF	Upregulated	[70]
D-COMP	Deamidation of COMP	Aging and progression of hip OA	S	Upregulated	[80]
Pentosidine	Advanced glycation end products	Degradation of ECM proteins and decrease proteoglycans synthesis	S, U	Upregulated	[83]
ADAMTs	A disintegrin and metalloproteinases	Cartilage degradation	Cartilage tissue	Upregulated	[89]
Adipokines (leptin visfatin, resistin, adiponectin)	Adipose tissue related proteins	Cartilage loss and degradation of ECM protein	S, SF	Upregulated except Adiponectin	[96]

S: serum; SF: synovial fluid; U: urine.