Obtaining regulatory T cells from uraemic patients awaiting kidney transplantation for use in clinical trials

Summary Adoptive transfer of regulatory T cells ( T regs ) has been proposed for use as a cellular therapy to induce transplantation tolerance. Preclinical data are encouraging, and clinical trials with T reg therapy are anticipated. In this study, we investigate different strategies for the isolation and expansion of CD 4 + CD 25 high CD 127 low T regs from uraemic patients. We use allogeneic dendritic cells ( DCs ) as feeder cells for the expansion and compare T reg preparations isolated by either fluorescence activated cell sorting ( FACS ) or magnetic activated cell sorting ( MACS ) that have been expanded subsequently with either mature or tolerogenic DCs . Expanded T reg preparations have been characterized by their purity, cytokine production and in‐vitro suppressive ability. The results show that T reg preparations can be isolated from uraemic patients by both FACS and MACS . Also, the type of feeder cells used in the expansion affects both the purity and the functional properties of the T reg preparations. In particular, FACS ‐sorted T reg preparations expanded with mature DCs secrete more interleukin ( IL) ‐10 and granzyme B than FACS ‐sorted T reg preparations expanded with tolerogenic DCs . This is a direct comparison between different isolation techniques and expansion protocols with T regs from uraemic patients that may guide future efforts to produce clinical‐grade T regs for use in kidney transplantation.