Response to Comment on Yi et al. Adoptive Transfer With In Vitro Expanded Human Regulatory T Cells Protects Against Porcine Islet Xenograft Rejection via Interleukin-10 in Humanized Mice. Diabetes 2012;61:1180–1191 Philip John O'Connell⇑ and Shounan Yi Centre for Transplant and Renal Research, Westmead Institute, University of Sydney at Westmead Hospital, Westmead, New South Wales, Australia Corresponding author: Philip John O’Connell, philip.oconnell{at}sydney.edu.au. We thank Ye et al.