 The study is a phase II, single center, open label, pilot study. We will recruit 12 patients with T1D to be randomly 1:1 assigned to receive islet either into the liver through the portal venous circulation standard procedure; arm A, n6 or directly into the BM at the level of the iliac crest arm B, n6. Patients will be selected from those eligible for islet Tx based on local practice and guidelines. 