Table 1.

Isolation of B. burgdorferi from selected tissues and arthritis development in ankles of control and cytokine knockout micea

StrainDayArthritis severitybNo. of cultures positive/no. tested
JointBloodHeartSpleenBladderEar
C3H212.1 ± 0.6*5/60/93/54/83/98/8
C3H IFN-γ°212.2 ± 0.6*8/112/114/106/1110/116/6
DBA211.1 ± 0.48/93/104/102/109/108/10
DBA IL-4°210.7 ± 0.59/133/133/131/1311/139/13
C3H601.0 ± 1.06/100/103/102/1010/108/10
C3H IFN-γ°601.3 ± 0.83/70/71/70/76/75/7
DBA600.3 ± 0.62/80/81/80/88/88/8
DBA IL-4°600.8 ± 0.710/163/168/166/1613/1616/16
  • a Mice were infected with 5 × 105B. burgdorferi organisms and sacrificed at 21 or 60 days. Tibiotarsal arthritis severity was scored on a scale from 0 to 3. (Means ± standard deviation are shown.)

  • b Asterisks indicate that C3H background severity scores were significantly higher than those of DBA background mice (P < 0.001).