Table 3.

Effect of IL-1ß and TNF-α on gene expression of different molecules in human chondrocytes

	Stimulus
Relative gene expression for	IL-1β	TNF-α
IL-6	2767 ± 176*	680 ± 49*
IL-8	5090 ± 271*	1088 ± 78*
MMP-3	112 ± 10.0*	71 ± 6.5*
MMP-13	7.5 ± 2.0*	6.5 ± 0.5*
TIMP-3	3.4 ± 0.7°	1.0 ± 0.1 ns
TIMP-4	1.9 ± 0.2°	1.0 ± 0.05 ns
iNOS	1656 ± 100*	1663 ± 110*

Primary human chondrocytes were cultured for 40 h in medium or in the presence of 10 ng/mL IL-1ß or TNF-α. RNA was purifiedd and analyzed by Real-time RT-PCR. Gene expression data were calculated with the ΔCT method and using HPRT1 and GAPDH as reference genes. Relative expression was obtained comparing samples to untreated control whose gene expression was considered as baseline. Data from 4 separate experiments (± S.E.M.) are shown

* p < 0.0001; °p < 0.02; ns: not significant vs untreated controls