Figure 5

Wt and IL-18 gene-knockout mice were administered zymosan to induce zymosan-induced arthritis (ZIA). Wt mice showed increases of hind joint (knee) circumference from 24 to 48 hours, with a pronounced reduction of swelling in comparative mice lacking IL-18. These data show that IL-18 is critical in acute inflammation of murine joints in as early as 24 hours after zymosan injection (n = number of joints analyzed).