Figure 2.

Conditional RGS12 KO in mice inhibits the development of CAIA. (A) CAIA was induced in LysM-Cre⁺ and LysM-Cre⁺;RGS12^fl/fl mice by injection 5 mg of a mAb mixture (Chondrex #53100) suspended in sterile PBS and subsequent challenge with 50 μg of LPS on day 3. At 9 days after immunization, the mice were sacrificed. (B) The paws of LysM-Cre⁺ and LysM-Cre⁺;RGS12^fl/fl mice were immunized with 5 mg of a mAb mixture for 9 days as described in (A). Note that LysM-Cre⁺;RGS12^fl/fl mice showed less swelling in the ankles (yellow double arrow) than LysM-Cre⁺ mice. (C) Ankle widths and (D) arthritis clinical scores of LysM-Cre⁺ and LysM-Cre⁺;RGS12^fl/fl mice were measured and evaluated every day for 9 days. Statistically significant differences (***, P<0.001) were observed between LysM-Cre⁺ and LysM-Cre⁺;RGS12^fl/fl mice. The data are expressed as the means ± SEM. (E) Hematoxylin and eosin (H&E) staining of RA synovial tissue samples from mice as described in (A) and (B). H&E staining showed a decrease in local inflammatory cell infiltration (yellow arrows) within synovial tissue in the LysM-Cre⁺;RGS12^fl/fl group (B, bone area). ***, P<0.001, n=5. Scale bar: 500 mm.