[C3H10 T1/2 cells over-expressing CCR7 have intensive immunosuppressive effect]

To evaluate whether the chemokine (C-C motif) receptor 7 (CCR7) over-expressing C3H10 T1/2 mesenchymal stem cells are more efficient in immunosuppression effects than the original ones in skin grafts in mice.

The C3H10 T1/2 cells were amplified and transfered with EGFP-CCR7 gene using lentivirus. The skin grafts were harvested from donators (C57BL/6 mice) and then transplanted to recipients (BALB/c mice). The recipients were divided into 4 groups randomly: CCR7⁺ C3H10 T1/2 group (1 × 10⁶ CCR7⁺ C3H10 T1/2 cells suspended in 1 mL PBS were injected into the recipient mice by caudal vein), C3H10 T1/2 group (1 × 10⁶ C3H10 T1/2 cells were injected into the recipient mice after skin graft), allogenic control group (the mice were injected with 1 mL normal saline), and congenic control group (the BALB/c mice that had received the skin from the congenic ones were injected with 1 mL normal saline). The skin graft survival condition and histopathological changes were observed on the 12th postoperative day. The Th17 cells and regulatory T cells (Tregs) in the lymphocytes of spleen were detected by mouse Th17/Treg phenotyping kit.

On the 12th postoperative day, the skin surface features, histopathologic changes and flow cytometry results indicated that the skin graft survival condition of the allografts treated with CCR7⁺ C3H10 T1/2 or C3H10 T1/2 cells were better than that of the allogenic control group. Compared with C3H10 T1/2 cells, CCR7⁺ C3H10 T1/2 cells had better skin graft survival condition and weaker immune response.

CCR7⁺ C3H10 T1/2 cells induce more intensive immunosuppressive effects than original C3H10 T1/2 cells. CCR7⁺ C3H10 T1/2 cells significantly inhibit inflammatory reaction and improve the living state of skin allograft.