Graft of tissue

Allograft A graft of tissue between two organisms of the same species those are not genetically identical. 

Autograft A graft of tissue from one part of the body to another. 

Isograft A graft of tissue between genetically identical individuals. 

Antigens, however, can induce a second type of response which is known as the cell-mediated immune response. The antigenic agent stimulates the appearance of sensitized lymphocytes in the body which confer protection against organisms that have the ability to live and replicate inside the cells of the host. Certain of these lymphocytes are also involved in the rejection of tissue grafts. 

Liver Fever, lethargy, change in color or quantity of bile in patients w/ biliary T-tube, graft tenderness and swelling, back pain, anorexia, ileus, tachycardia, jaundice, ascites, encephalopathy Abnormal LFTs, increased bilirubin, alkaline phosphatase, transaminases, biopsy positive for mononuclear cell infiltrate with evidence of tissue damage... 

A potentially promising, although very controversial, approach to the treatment of Parkinson s disease is replacement of dopaminergic neurons. The grafting of fetal substantia nigra tissue, which contains the dopamine neurons, into the striatum of parkinsonian patients has been modestly successful. The procedure will remain experimental, however, until the many practical problems and ethical issues associated with the use of fetal tissue are resolved. The discovery of pluripotent stem cells is also being viewed as a possible way of developing dopamine neurons for transplant purposes. 

Antiserum can be raised againsf lymphocyfes or fhymo-cyfes by fhe repealed injection of human cells into an appropriate recipient, usually a horse. The use of such antiserum or the immune globulin fraction derived from it has been used to produce immunosuppression. Although antilymphocytic serum can suppress cellular and often humoral immunity against a variety of tissue graft systems, the responses are variable, particularly from one batch of serum to another. 

George, S.J., C.T. Lloyd, G.D. Angehni,A.C. Newby, and A.H. Baker, Inhibition of late vein graft neointima formation in human and porcine models by adenovirus-mediated overexpression of tissue inhibitor of metalloproteinase-3. Circulation, 2000.101(3) 296-304. 

Fig. 7.1 Phases of tissue transplant rejection. The transplanted tissue sheds antigens. These antigens undergo uptake, processing and presentation to the T cells in the secondary lymphoid tissue by APCs, which include macrophages, B cells, Langerhans cells or dendritic cells. This phase results in the production of antibodies and antigen-specific TH and Tc cells. The antibodies and effector cells then migrate to the grafted tissue where TH cells secrete cytokines and which in combination with the antibodies and Tc cells destroy the grafted tissue (see Color Insert)...

Adhesion molecules also play a crucial role in allograft rejection. The migration of activated T cells from secondary lymphoid organs to the graft site is regulated by adhesion molecules. Furthermore, these molecules are pivotal in the interaction of T cells with the functional components of tissue allografts that are epithelial in origin. 

There are many different procedures used for pancreas transplantation, and there is no one standard protocol used in all transplant centers. The important considerations, however, are that the arterial blood flow supply to the pancreas and duodenal segment, and venous outflow from the pancreas via the portal vein should be adequate. The recipient s right common or external iliac artery is used to restore vascularization of the artery in the pancreas. The Y graft of the tissue is anastomosed end-to-side and the venous vascularization is performed either systemically or portally, but mostly it is done with systemic venous drainage. 

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