title: Immunosuppression in islet transplantation.
abstract: Islet transplantation can temporarily cure type 1 diabetes mellitus (T1DM) but requires simultaneous immunosuppression to avoid allograft rejection. In this issue of the JCI, Monti et al. report that immune conditioning via use of the Edmonton protocol - a treatment approach in which T1DM patients infused with pancreatic islets from multiple cadaveric donors simultaneously receive immunosuppressive drugs - results in lymphopenia that is associated with elevated serum levels of the homeostatic cytokines IL-7 and IL-15, which causes in vivo expansion of the autoreactive CD8(+) T cell population (see the related article beginning on page 1806). Reemergence of autoreactivity is likely the main culprit underlying long-term islet graft failure, and new strategies will need to be tested to circumvent this homeostatic expansion and recurrent autoreactivity.
authors.affiliation: La Jolla Institute for Allergy and Immunology, La Jolla, California 92037, USA.
authors.forename: Tom
authors.initials: T
authors.lastname: Van Belle
authors.forename: Matthias
authors.initials: M
authors.lastname: von Herrath
mesh_terms: D000818:Animals; D015551:Autoimmunity / Q000502:physiology; D003922:Diabetes Mellitus, Type 1 / Q000628:therapy; D006084:Graft Rejection / Q000517:prevention & control; D006706:Homeostasis; D006801:Humans; D007165:Immunosuppression Therapy / Q000379:methods*; D007166:Immunosuppressive Agents / Q000009:adverse effects / Q000627:therapeutic use; D016381:Islets of Langerhans Transplantation / Q000276:immunology*; D051379:Mice; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
chemical_list: D007166:Immunosuppressive Agents