Retinoic acid can enhance conversion of naive into regulatory T cells independently of secreted cytokines

J Nolting, C Daniel, S Reuter, C Stuelten, P Li, H Sucov, B. G Kim, J. J Letterio, K Kretschmer, H. J Kim and H. von Boehmer

The Journal of Experimental Medicine 206 ( 10 ): 2131 - 2139 , 2009