Rat Hindlimb Allotransplantation with Short-term Immune Suppressants and Dendritic Cell Pretreatment

ABSTRACT

Prevention of acute rejection in composite tissue allotransplantation without continuous immunosuppression lacks reports in worldwide literature. Recently dendritic cells (DC) gained considerble attention as antigen presenting cells that are also capable of immunologic tolerance induction. This study assesses the effect of alloantigen-pulsed dendritic cells in induction of survival in a rat hindlimb allograft. We performed hindlimb allotransplantation between donor Sprague-Dawley and recipient Fischer344 rats. Recipient derived dendritic cells were harvested from rat whole blood and cultured with anti-inflammatory cytokine IL-10. Then donor-specific alloantigen pulsed dendritic cells were reinjected into subcutaneous tissue before limb transplantation. Groups I) untreated (n=6), II) DC injected (n=6), III) Immunosuppressant (FK-506, 2 mg/Kg) injected (n=6), IV) DC and immunouppressant injected (n=6). Graft appearance challenges were assessed postoperatively. Observation of graft appearance, H-E staning, immunohistochemical (IHC) study, and confocal immunofluoreiscece were performed postoperatively. Donor antigen pulsed host dendritic cell combined with short-term immunosuppression showed minimal mononuclear cell infiltration, regulator T cell presence, and could prolong limb allograft survival.