KIR and their HLA Class I ligands: Two more pieces towards completing the puzzle of chronic rejection and graft loss in kidney transplantation. oleh Roberto Littera, Gianbenedetto Piredda, Davide Argiolas, Sara Lai, Elena Congeddu, Paola Ragatzu, Maurizio Melis, Elisabetta Carta, Maria Benigna Michittu, Donatella Valentini, Luisella Cappai, Rita Porcella, Francesco Alba, Maria Serra, Valentina Loi, Roberta Maddi, Sandro Orrù, Giorgio La Nasa, Giovanni Caocci, Roberto Cusano, Marcella Arras, Mauro Frongia, Antonello Pani, Carlo Carcassi