Mechanical properties of nucleus pulposus constructs (n = 5) treated with IL-1β or IL-1ra conditioned media or both were evaluated in confined compression. (a) Aggregate modulus (HA). (b) Hydraulic permeability (k0). Values are mean ± standard deviation. *P < 0.05 versus untreated constructs; ◆P < 0.05 versus IL-1β-only treated constructs. IL-1β, interleukin-1 beta; IL-1ra, interleukin-1 receptor antagonist; N.s., Newton second.
Gorth et al. Arthritis Research & Therapy 2012 14:R179 doi:10.1186/ar3932