Table 1.

Joint inflammation in FcR γ-chain^-/-, wild-type C57BL/6, and DBA/1 mice

	Days after induction of ICA
	1		3		7		14
Mouse strain	Infiltrate	Exudate	Infiltrate	Exudate	Infiltrate	Exudate	Infiltrate	Exudate
FcRγ-/-	0.4 ± 0.1	0.3 ± 0.2	0.1 ± 0.1*	0.1 ± 0.1*	ND	ND	ND	ND
C57BL/6	1.4 ± 0.1	0.8 ± 0.2	1.4 ± 0.3	1.5 ± 0.4	1.2 ± 1.2	0.5 ± 0.6	0.4 ± 0.3	0
DBA/1	ND	ND	2.1 ± 0.2*	1.8 ± 0.3	3.0 ± 0*	2.5 ± 0.4*	2.1 ± 0.3*	1.6 ± 0.2*

Cellular score in knee joints 3, 7, and 14 days after induction of ICA in knee joints of FcR γ-chain^-/-, C57BL/6, and DBA/1 mice. The amount of inflammatory cells in the joint cavity (exudate) and in the synovial layer (infiltrate) were scored blind by two independent observers, on an arbitrary scale from 0-3 (0 = no; 1 = minor; 2 = moderate; 3 = maximal). Note that FcR γ-chain^-/- mice show markedly less inflammation and that knee joints of DBA/1 mice were significantly more inflamed at all time points in comparison with C57BL/6 mice. Data are means of scores for six mice, and significance (FcR γ-chain^-/- versus C57BL/6, and DBA/1 versus C57BL/6) was evaluated using the Mann-Whitney U test (^*P < 0.05). ND, not done.