The Influence of Timing and Frequency of Adipose-derived Mesenchymal Stem Cell Therapy on Immunomodulation Outcomes after Vascularized Composite Allotransplantation.

Background: Cellular therapies for immunomodulation in vascularized composite allotransplantation (VCA) have gained importance due to their potential minimization of immunosuppression. Adipose-derived mesenchymal stem cells (AD-MSCs) especially have shown encouraging potential. We investigated the influence of timing and frequency of AD-MSC-treatment on immunologic and graft survival as well as graft vasculopathy (GV) outcomes after VCA. Methods: Lewis (LEW) rats received full-mismatched Brown Norway (BN) rat hindlimb transplants. Recipient animals were assigned to groups receiving donor-derived AD-MSCs (106 cells/animal) either on postoperative day (POD) 1, POD 4, or repeatedly on POD 4, 8, and 15, and compared to untreated controls. Results: While AD-MSC administration on POD 1 or POD 4,8,15 resulted in 50% long-term graft acceptance, recipients treated on POD 4 and controls rejected prior to POD 50. All treated animals revealed peripheral blood chimerism (4 weeks), most pronounced following repetitive cell administration (12.92% vs. 5.03% [POD 1] vs. 6.31% [POD 4]; p

http://ift.tt/2gQZB3L