Mechanisms of Graft Rejection and Acceptance: Pathways to a New Clinical Era

07:20 Cell-Mediated Rejection: An Expanding Definition
Allan D. Kirk, Emory University, Atlanta, USA

Multiple cell types infiltrate acutely rejecting allografts. Typically, T cells and monocytes predominate, and of these, T cells are known to be required for acute rejection. Indeed, the basis for modern maintenance immunosuppression is inhibition of T cell function. The basis for this practice will be briefly acknowledged. However, a substantial portion of this talk will be devoted toward a broader definition of cellular rejection, specifically examining the role of monocytes, platelets and neutrophils. Data will be presented relating these other cell types to the phenotype of acute rejection and the magnitude of the functional impact of alloimmune responses. The relative contribution of all hematopoietic cells to allograft outcome will be discussed in the context of acute changes, chronic fibrosis, and clinical interpretation of graft histopathology.