Transplant immunity Flashcards
transplant rejection
when a kidney is transplanted, the recipient’s T cells attack the transplant
graft vs host disease
when the bone marrow is transplanted, the T cells in the transplant attack the recipient’s tissue
blood group antigens
simple polysaccharide, body makes antibodies against antigen we don’t have. body only makes antibodies against Rh after initial exposure
hyperacute rejection
most severe and immediate type of rejection. caused by preformed antibodies that react to the transplanted organ.
reasons why someone may have antibodies to HLA (IgG antibodies)
previous transplant, blood transfusions, woman who gives birth
panel reactive antibody
serum of a recipient is tested against a panel of leukocytes from many individuals, detection of the presence of antibodies to HLA
acute rejection
process in which T cells from the recipient becomes reactive against transplant. process takes days to weeks. stronger response is to donor cells expressing MHC class 2.
where most immune suppression therapies are directed towards.
chronic rejection
takes months or years. result of indirect recognition of the transplant. towards MHC molecules or other minor transplantation antigens. associated with the presence of antibodies to HLA-class 1 antigens in the graft which seem to act on the vasculature of the graph.
alloantibodies
against same species, different MHC.
Prevent Rejection by
matching HLA, testing at transplantation, workup for transplantation, anti ABC antibody testing
corticosteroids
transplant therapy, interferes with transcription factor needed to turn on the genes for T cells to become activated. reduce inflammation.
ex. prednisone, prednisolone
cytotoxic drugs
transplant therapy, interfere with DNA synthesis, interferes with rapid cell proliferation needed for immune response
ex. azathioprine, imuran (purine analog)
FK506 and cyclosporine
inhibit the signaling pathway used by T cells to turn on their genes for activation
Antilymphocyte (thymocyte) globulin (ALG or ATG)
contains antibodies from horses or rabbits directed against T cells so no serum sickness
CTLA4-IG
protein produced by recombinant DNA technology
binds with B7 so cell cannot present antigen to T cell.
