<qa>  What is the aim of the study?Studys aim: to perform IS conversion from CNI to MMF monotherapy and look for transcriptional biomarkers employing whole a genome expression study performed with microarrays at baseline on liver tissue and PBMCs to try to find a set differentially expressed genes able to correlate with a successful conversion and thus, to generate a set of transcriptional biomarkers potentially able to predict the result of the IS conversion on an independent cohort of liver recipients. 