Table 1

Incidence of Arthritis in IL-1ra−/− Mice in Different Genetic Backgrounds

AgeBALB/cAC57BL/6J129 × C57BL/6J
wk
824/30 (80)0/56 (0)0/114 (0)
1656/56 (100)0/56 (0)0/114 (0)
24ND1/13 (8)0/17 (0)
32ND2/13 (15)0/2 (0)
482/2 (100)2/7 (29)ND
  • Arthritic mice/total mice examined. Numbers in parentheses show the incidence (%) of arthritic mice.