The focus of this project is a novel immunomodifying therapy that provides protection from early allograft rejection in the absence of the standard toxic systemic immunosuppressive drug regimens. This novel therapy is a nano-barrier membrane called NB-LVF4 consisting of a matrix made of laminin, vitrogen, fibronectin and type IV collagen. NB-LVF4 is applied to "immunocloak" the luminal surfaces within the renal vasculature by covering the point of contact between donor vascular endothelial cells and the host immune system;without adversely affecting renal function. The result is an apical surface that is non-thrombogenic and non- immunogenic and significantly delays the onset of rejection 5-fold over untreated controls by preventing allo- recognition that normally occurs immediately upon reperfusion. A warm acellular Exsanguinous Metabolic Support (EMS) perfusion technology that is entering clinical trials is the platform used to apply NB-LVF4. The immunocloaking technology will be a follow-on product that can be applied to a kidney allograft during ex vivo EMS perfusion. If the results of our studies support our hypotheses and prove that: 1. the immunogenicity of renal allografts can be further reduced by trapping passenger leukocytes that migrate into the recirculating EMS perfusate to prevent reentry into the kidney, 2. the use of a concordant low-dose immunosuppressive drug monotherapy potentiates long-term graft survival, 3. the mechanisms of protection provided by NB-LVF4 are fully elucidated, along with an understanding of how it degrades over time along the vasculature and 4. a strategy for the organ-specific re-application of NB-LVF4 posttransplant to replace systemic drug regimens can be achieved, the NB-LVF4 technology will mark a new era in transplantation. It is envisioned that the ability to eliminate toxic systemic immunosuppressive drug regimens will lead to a paradigm shift where instead of daily immunosuppressive drug regimens it will become feasible to re-administer NB-LVF4 every three to four weeks. However, even if these goals are not fully achieved, NB-LVF4 will still be clinically relevant. The ability to use NB-LVF4 treatment to eliminate systemic immunosuppression during the early posttransplant period will be important to expanding the cadaveric kidney donor pool with warm ischemically damaged DCD kidneys. The acute tubule necrosis that is the result of ischemic damage leads to delayed graft function that in turn is associated with the risk of developing currently untreatable chronic rejection. By eliminating the need for systemic immunosuppressive drugs, that are in of themselves nephrotoxic, during the early posttransplant period of acute tubule necrosis the severity and duration of delayed graft function would be ameliorated. The consultants and collaborators involved in this project are internationally recognized experts in their respective field and their involvement in this project will significantly increase the likelihood of successfu outcomes.
The goal of this project is use new technology referred to as immunocloaking to eliminate the need for the toxic chronic systemic immunosuppressive drug regimens that are the standard-of-care today. We have developed a product referred to as the NB-LVF4 nano-barrier membrane that can be applied pre- transplantation in an organ-specific manner to immunocloak the interface between the donor graft vasculature and the recipient's immune system. The goal of this project is to develop the ability to reapply NB-LVF4 post- transplantation where instead of daily multi-drug regimens, NB-LVF4 will be administered intravascularly once a month.