Table 2.

Classification of cytokines and growth factors in OA. Cytokines and growth factors that are currently believed to have a catabolic, regulatory, anti-catabolic or anabolic role in OA are shown

Catabolic	Anabolic	Anti-catabolic	Regulatory
IL-1	Activin	IL-1ra	IL-1
IL-17 IL-18	BMP-2,-4, -6, -7, -9, -13	IL-4	IL-6
OSM	CTGF	IL-10	LIF
TNF	FGF-2	IL-13
	IGF-1
	TGF-β

IL, interleukin; OSM, oncostatin M; LIF, leukaemia inhibitory factor; IL-1ra, IL-1 receptor antagonist; IGF-1, insulin-like growth factor-1; FGF-2, fibroblast growth factor-2; CTGF, connective tissue growth factor.