Antigen-Specific T Cells Transduced with IL-10 Ameliorate Experimentally Induced Arthritis Without Impairing the Systemic Immune Response to the Antigen

Left, Photomicrograph of hematoxylin-eosin-stained section of an ankle joint 21 days after intra-articular injection of OVA to a mouse primed with OVA. There is hypertrophy of the synovium (s), a dense cellular infiltration into the articular cavity, and periarticular lesions. Right, Ankle joint of a mouse treated with DO11.10 T cells transduced with mIL-10.

Removal of nontransfected cells reduced the number of transduced T cells needed to ameliorate the arthritis. Before the transfer, GFP-expressing CD4⁺ DO11.10 splenocytes that were transduced with pMFGmIL10-IRES-GFP were selected. The maximum hind paw thickness in each group is shown. The maximum swelling usually occurred on day 1. The number of transferred cells was 1 × 10⁴ (▨), 5 × 10⁴ (□), and 1 × 10⁵ (▪). The results from mice transferred with the same number of mock-transfected DO11.10 CD4⁺ T cells are also shown (1 × 10⁴ (▨), 5 × 10⁴ (□), and 1 × 10⁵ (▪)). As a control, the results for mice given only PBS are shown at the center of the panel (▩). Bars show the mean ± SD (n = 10/group). The difference between the control group and the groups of mice transferred with GFP-selected cells was statistically significant (∗, p < 0.01; ‡, p < 0.05), whereas the difference between the control group and the groups of mice transferred with mock-transfected cells was not significant.

Ag specificity is required to ameliorate AIA. The percent inhibition of the maximum hind paw thickness is shown. The number of transferred cells was 5 × 10⁵ (▪) and 1 × 10⁶ (□). The same number of DO11.10 CD4⁺ T cells transduced with mIL-10 was transferred. Bars show the mean ± SD (n = 10/group). Compared with the control group, a significant difference (∗, p < 0.01) was observed in each group of mice transferred with IL-10-transduced DO11.10 CD4⁺ T cells, whereas no statistical difference was observed in the groups of mice transferred with IL-10-transduced CD4⁺ BALB/c splenocytes.

TCR-RT-PCR/SSCP revealed the accumulation of transferred DO11.10 T cells in the ankle joint. Spleen, right foreleg, left foreleg, right ankle joint, and left arthritic ankle joint (from lanes 2–6) of a mouse with AIA and transferred with DO11.10 T cells are shown. As a reference, the spleen of a BALB/c mouse immunized with OVA without transfer of DO11.10 T cells (lane 7) and the spleen of a DO11.10 mouse (lanes 1 and 8) are also shown.

The selective accumulation of the transferred T cells in the arthritic joint was confirmed by flow cytometry. Cells were recovered from spleens (A) as well as joints (B) from mice that had been transferred with DO11.10 CD4⁺ T cells transduced with pMFGmIL10-IRES-GFP and selected by GFP expression. Because DO11.10 clonotype-positive cells are exclusively CD4 positive, the results of analysis using KJ1-23 are similar to those of analysis using CD4. In one experiment three arthritic mice were sacrificed, and their cells were mixed before staining. A representative result is shown. Three separate experiments gave similar results.

Neither the T cell nor the B cell response against OVA was impaired by transfer of 5 × 10⁵ DO11.10 CD4⁺ T cells transduced with mIL-10. A, Proliferation assay upon OVA challenge. The proliferation of splenocytes from OVA-primed BALB/c mice transferred with PBS (▪), DO11.10 CD4⁺ T cells mock-transfected (□), and DO11.10 CD4⁺ T cells transfected with mIL-10 (▨), respectively, were measured by [³H]thymidine incorporation in the presence of 10 μg/ml OVA. Bars show the mean ± SD (n = 10/group). The difference between each group was not significant. B, Anti-OVA Ab level. Mice were bled 30 days after intra-articular challenge with OVA, and blood was assayed for the anti-OVA Ab level by ELISA. The mean Ab titer (±SD) of each group of 10 mice is shown. The difference between each group was not significant.