Figure 4. Spinal cord recruits Treg cells through CCL28-CCR10 axis after SCI. (A) Mouse peripheral blood mononuclear cells (PBMCs) were seeded in the upper chambers and pretreated with control antibody (Ctrl Ab), neutralizing antibodies against CCL28, CCR10 or CCR3 for 1 hr. The percentage of CD4+CD25+FOXP3+ Treg cells among the CD4+ cells recruited to the lower chambers with medium containing mouse recombinant CCL28 (rMCCL28) or 1% mouse control serum was analyzed by flow cytometry (n=6 replicates in each group). (B) Mice were pre-injected with Ctrl Ab or neutralizing antibodies against CCL28 (anti-CCL28), CCR10 (anti-CCR10) or CCR3 (anti-CCR3) into the intraspinal cord for 12 hrs, and then subjected to sham or SCI surgery. After another 12 hrs, the percentage of CD4+CD25+FOXP3+ Treg cells in the spinal cord was determined by flow cytometry analysis (n=5). (C) Mice were pre-injected with Ctrl Ab, anti-CCL28 or anti-CCR10 and rMCCL28 or 1% mouse control serum as indicated into the intraspinal cord for 12 hrs, and then subjected to sham or SCI surgery. After another 12 hrs, the percentage of CD4+CD25+FOXP3+ Treg cells in the spinal cord were determined (n=5). Data are mean ± SD. The statistical analysis was performed using Student’s t-test. **, P<0.01; NS, not significant.