However, the CCR5-mediated regulatory function of CD4+Foxp3+ Tregs was likely to be relatively unimportant in JE progression, because adoptive transfer of CCR5+CD4+Foxp3+ Tregs between 2 and 4 dpi ameliorated JE progression, whereas CD4+Foxp3+ Tregs that were adoptively transferred prior to JEV infection rendered the recipients vulnerable to JE (unpublished personal data). This evidence concerns the gene FOXP3 and Japanese encephalitis.