ation. However, it is not known if all CD4+ T cells have the same capacity to express FOXP3. To investigate whether FOXP3 can be expressed by any T cell subset or if expression is restricted to a distinct lineage, FOXP3 mRNA expression was analyzed in freshly isolated T cells such as CD25-depleted CD4+ cells, CD45RA+ naive or CD45RO+ memory T cells (Figure