We provided evidence that injection of sorted CCR5+CD4+Foxp3+ Tregs into Ccr5−/− mice ameliorated JE progression without affecting CNS infiltration of IL-17+CD4+ Th17 cells, myeloid-derived Ly-6Chi monocytes, and Ly-6Ghi granulocytes. The gene discussed is CCR5; the disease is Japanese encephalitis.