The ideal biomarker of autoimmunity recurrence would be, in addition to the autoantibodies, the finding of circulating islet autoantigen-specific T-cell clones (CD4 and CD8) in the peripheral blood, preceding the loss of c-peptide in islet transplant recipients, but there are several limitation to these assays and they are not widely available (27). Here, CD4 is linked to Autoimmunity.