Tissue transplantation acute rejection

Even if tissue types are dosely matched, transplanted organs are usually rejected unless preventive measures are taken. Rejection, if it occurs, can begin soon after transplantation - acute rejection - but can... 

Mycophenolate mofetil is used for tissue transplantation in combination with tacrolimus or cyclosporine or sirolimus plus glucocorticoids. It is used more than any other cytotoxic drug either at the time of the transplant or following the initiation of acute rejection. Mycophenolate mofetil is a prophylactic agent and cannot be used for chronic rejection or ongoing acute rejection. 

Daclizumab is used for the prophylaxis of acute rejection in patients receiving kidney transplants. A dose of 1 mg/kg is sufficient to completely block all the IL-2 receptors. It is administered in five doses at a 2-week interval where its elimination half-life is about 20 days. A combination of several other immunosuppressive agents including cyclosporine (or tacrolimus, rapamycin), mycophenolate mofetil and corticosteroids can be used with daclizumab. When it is used in combination with tacrolimus, the doses of tacrolimus are reduced. After tissue transplantation, the addition of daclizumab to the standard immunosuppressive regimen produces reduction in tissue rejection up to 50%. Daclizumab can cause hypersensitivity reactions, but it does not cause cytokine-release syndrome. There is a low incidence of... 

Basiliximab is used for the prophylaxis of acute rejection for patients undergoing kidney transplantation where it is employed in combination with other standard immunosuppressive therapy regimens. After tissue transplantation, its addition to the standard immunosuppressive regimen results in inhibiting tissue rejection up to approximately 30%. Both daclizumab and basiliximab have similar effects on the expression of IL-2a and -(3 chains. 

Gastrointestinal Gastrointestinal adverse events are among the main limitations of the use of mycophenolate mofetil. Examination of the surface epithelium, lamina propria, and crypts of mucosal intestinal biopsy tissue in 15 multivisceral transplant patients, including stomach, small intestine, and colon, showed neither specific changes that could be associated with mycophenolate mofetil toxicity nor changes that could differentiate mycophenolate mofetil-related toxicity from acute rejection [88 ]. 

Acute cellular rejection involves infiltration of macrophages and lymphocytes into the graft and is evident from the necrosis of the parenchymal cells of the graft. The lysis of the parenchymal cells of the transplanted tissue is achieved by the infiltrating leukocytes. Acute cellular rejection may be the product of several mechanisms including cytolytic T-cell-mediated lysis, NK cell-mediated lysis and activated macrophage-mediated lysis. The acute cellular rejection predominantly involves CD8+ T cytolytic cells that kill the grafted tissue. 

The application of antibodies in cardiovascular targeting in vivo originated with the experimental demonstration of the feasibility of using radiolabeled antimyosin antibody for diagnosis of acute myocardial infarction in 1976. Since then, the use of antibodies in the cardiovascular system has encompassed imaging of myocarditis,heart transplant rejection, dilated cardiomyopathy, alcohol induced cardiomyopathy,adriamycin cardiotoxicity, various other cardiomyopathies, vascular clots, atherosclerotic lesions,and even certain cancers such as soft tissue sarcomas.f Yet the best characterized and studied antibody for cardiovascular diagnostic targeting is monoclonal antimyosin Fab for its exquisite specificity... 

JoseMD, Ikezumi Y,Van Rooijen N, Atkins RC, Chadban SJ Macrophages act as effectors of tissue damage in acute renal allograft rejection.Transplantation 76 1015-1022,2003... 

Scheduled bronchoscopies are performed routinely during the first year after transplantation at most transplant centres. Inspection of the anastomotic sutures, control of anastomotic wound healing, BAL with microbiologic cultures and transbronchial biopsies are taken to document lung tissue quality and to diagnose acute or chronic lung rejection, invasive infections and eventually to perform interventional procedures such as dilatation or stenting of bronchial stenosis. 

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