Rapamycin-mediated enrichment of T cells with regulatory activity in stimulated CD4+T cell cultures is not due to the selective expansion of naturally occurring regulatory T cells but to the induction of regulatory functions in conventional CD4+T cells - Valmori, D; Tosello, V; Souleimanian, N E; Godefroy, E; Scotto, L; Wang, Y; Ayyoub, M (J Immunol, 2006)