FOXP3 and post-traumatic stress disorder: In addition to determining percentages of total Tregs (CD3+CD4+CD25+FOXP3+) in peripheral blood of PTSD patients, we further characterized Tregs according to their expression of HLA-DR, CD127 and CD39 to investigate whether PTSD patients exhibit a different phenotype of Tregs (possibly functionally distinct) compared to healthy controls.