Grafting and Transplantation Flashcards
What is an autograft?
A graft from self (p.208)
What is an allograft?
From a non-identical individual of the same species (p.208)
What is a xenograft?
From a different species (p.208)
What is a syngeneic graft?
From an identical twin or clone (p.208)
When does a hyperacute transplant rejection occur?
Within minutes of transplant (p.208)
When does an acute transplant rejection occur?
Weeks after transplant (p.208)
When does a chronic transplant rejection occur?
Months to years after transplant (p.208)
When does a graft vs host reaction occur?
Variable timeframe (p.208)
What is the pathogenesis associated with a hyperacute transplant reaction?
Antibody mediated type II reaction due to the presence of preformed anti-donor antibodies in the transplant recipient (p.208)
What is the pathogenesis associated with an acute transplant reaction?
A cell mediated reaction due to CTLs reacting against foreign MHCs (p.208)
What is the pathogenesis associated with a chronic transplant reaction?
Class I MHC nonself is perceived by CTLS as class I MHC self presenting as a non-self antigen (p.208)
What is the pathogenesis associated with a graft-vs-host reaction?
Grafted immunocompetent T cells proliferate in the irradiated immunocompromised disease host and reject cells with ‘foreign’ proteins resulting in severe organ dysfunction (p.208)
What are the features of a hyperacute transplant reaction?
Occlusion of graft vessels causing ischemia and necrosis (p.208)
What are the features of an acute transplant reaction?
Vasculitis of graft vessels with dense interstitial lymphocytis infiltrate (p.208)
What are the features of a chronic transplant reaction?
Irreversible T cell and antibody mediated vascular damage (obliterative vascular fibrosis); fibrosis of graft tissue and blood vessels (p.208)