In the long-term treatment of the pellets with the cytokine combination, although a significant upregulation of mRNA expression of arthritis-related proinflammatory cytokines, IL-6 and TNF-α, together with the mediator, COX2, was detected within 24 h, a striking increase in the expression of these genes was demonstrated after 2 weeks. Here, TNF is linked to arthritic joint disease.