Table 2.

IL-1 and IL-1Ra production (pg/ml) in knee joints of mice after induction of immune-complex-mediated arthritis (ICA) and zymosan-induced arthritis (ZIA)

	During ICA			During ZIA
	IL-1Ra	IL-1β		IL-1β
Mouse strain	At 6 h	At 6 h	At 24 h	At 6 h	At 24 h
FcRγ-/-	180 ± 15	200 ± 23	<20*	ND	ND
C57BL/6	215 ± 20	240 ± 21	70 ± 12	>1000	550 ± 30
DBA/1	ND	390 ± 43*	120 ± 15*	>1000	565 ± 5

Production of IL-1Ra at 6 h and IL-1β at 6 and 24 h after induction of ICA and ZIA in knee joints of three mouse strains. IL-1β was measured using a radioimmunoassay. Data are means ± SD of at least 5 mice and were evaluated using the Mann-Whitney U test (^*P < 0.05). ICA, immune-complex-mediated arthritis; IL-1Ra, IL-1 receptor antagonist; ND = not done; ZIA, zymosan-induced arthritis.