| graft enhancement, immunologic | The induction of prolonged survival and growth of allografts of either tumours or normal tissues which would ordinarily be rejected. It may be induced passively by introducing graft-specific antibodies from previously immunised donors, which bind to the graft's surface antigens, masking them from recognition by T-cells; or actively by prior immunization of the recipient with graft antigens which evoke specific antibodies and form antigen-antibody complexes which bind to the antigen receptor sites of the T-cells and block their cytotoxic activity. (12 Dec 1998) |
|---|---|
| graft occlusion | <physiology> Obstruction of flow in biological or prosthetic vascular grafts. (12 Dec 1998) |
| graft rejection | <haematology, immunology> When donated bone marrow infused during a bone marrow transplant is rejected by the patients body or does not take. (16 Dec 1997) |
| graft survival | <haematology> The survival of a graft in a host, the factors responsible for the survival and the changes occurring within the graft during growth in the host. (12 Dec 1998) |
| graft-versus-host disease | <haematology> A common and serious, complication of bone marrow transplantation where there is a reaction of donated bone marrow against a patient's own tissue. When donor lymphocytes or a graft containing lymphocytes that are immunologically competent are given to a patient that has low immunological competence, an incompatibility reaction can result. This is due to antibodies from the donor against antigens in the host. This is due to mismatch of MHC Class I antigens and can produce lymphocyte clones that will react by a variety of processes against the host and cause damage. The clinical condition can be fatal and is due to the donor's immune cells recognising the host cells as foreign. The clinical entity characterised by anorexia, diarrhoea, loss of hair, leukopenia, thrombocytopenia, growth retardation, and eventual death brought about by the graft-versus-host reaction. It can occur in either chronic or acute forms and is treatable by immunosuppressive drugs. Seen most commonly following bone marrow transplantation, acute disease is seen after 5-40 days and chronic disease weeks to months after transplantation, affecting, principally, the gastrointestinal tract, liver, and skin. Radiological appearances of the gastrointestinal tract include; thickened wall, mucosal folds thickened or effaced, increased secretions most likely to be rapid transit of GI tract, mass most likely to be focal oedema, fibrosis, hallmark: diffuse, uniform thickening of small bowel. Synonym: GVH disease. Acronym: GVHD (20 Sep 2002) |
| graft-versus-host reaction | <haematology> A common and serious, complication of bone marrow transplantation where there is a reaction of donated bone marrow against a patient's own tissue. When donor lymphocytes or a graft containing lymphocytes that are immunologically competent are given to a patient that has low immunological competence, an incompatibility reaction can result. This is due to antibodies from the donor against antigens in the host. This is due to mismatch of MHC Class I antigens and can produce lymphocyte clones that will react by a variety of processes against the host and cause damage. The clinical condition can be fatal and is due to the donor's immune cells recognising the host cells as foreign. The clinical entity characterised by anorexia, diarrhoea, loss of hair, leukopenia, thrombocytopenia, growth retardation, and eventual death brought about by the graft-versus-host reaction. It can occur in either chronic or acute forms and is treatable by immunosuppressive drugs. Seen most commonly following bone marrow transplantation, acute disease is seen after 5-40 days and chronic disease weeks to months after transplantation, affecting, principally, the gastrointestinal tract, liver, and skin. Radiological appearances of the gastrointestinal tract include; thickened wall, mucosal folds thickened or effaced, increased secretions most likely to be rapid transit of GI tract, mass most likely to be focal oedema, fibrosis, hallmark: diffuse, uniform thickening of small bowel. Synonym: GVH disease. Acronym: GVHD (20 Sep 2002) |
| graft-versus-host response | <haematology> A common and serious, complication of bone marrow transplantation where there is a reaction of donated bone marrow against a patient's own tissue. When donor lymphocytes or a graft containing lymphocytes that are immunologically competent are given to a patient that has low immunological competence, an incompatibility reaction can result. This is due to antibodies from the donor against antigens in the host. This is due to mismatch of MHC Class I antigens and can produce lymphocyte clones that will react by a variety of processes against the host and cause damage. The clinical condition can be fatal and is due to the donor's immune cells recognising the host cells as foreign. The clinical entity characterised by anorexia, diarrhoea, loss of hair, leukopenia, thrombocytopenia, growth retardation, and eventual death brought about by the graft-versus-host reaction. It can occur in either chronic or acute forms and is treatable by immunosuppressive drugs. Seen most commonly following bone marrow transplantation, acute disease is seen after 5-40 days and chronic disease weeks to months after transplantation, affecting, principally, the gastrointestinal tract, liver, and skin. Radiological appearances of the gastrointestinal tract include; thickened wall, mucosal folds thickened or effaced, increased secretions most likely to be rapid transit of GI tract, mass most likely to be focal oedema, fibrosis, hallmark: diffuse, uniform thickening of small bowel. Synonym: GVH disease. Acronym: GVHD (20 Sep 2002) |
| mesh graft | A skin graft in which multiple slits have been made, so it can be stretched to cover a large area. Synonym: mesh graft. (05 Mar 2000) |
| periosteal graft | A graft of periosteum, usually placed on bare bone. (05 Mar 2000) |
| chip graft | A graft utilizing small pieces of cartilage or bone which is packed into a bone defect. (05 Mar 2000) |
| chorioallantoic graft | Transplanting of living material to the chorioallantoic membrane of the embryonic chick. (05 Mar 2000) |
| Phemister graft | An autogenous onlay bone graft used in treating delayed union of fractures. (05 Mar 2000) |
| pinch graft | Small bits of skin, of partial or full thickness, removed from a healthy area and seeded in a site to be covered. Synonym: Reverdin graft. (05 Mar 2000) |
| white graft | Rejection of a skin allograft so acute that vascularization never occurs. (05 Mar 2000) |
| composite graft | A graft composed of several structures, such as skin and cartilage or a full-thickness segment of the ear. (05 Mar 2000) |