Flashcards in Transplant Deck (28):
What is graft rejection?
Graft rejection is an example of where the immune response acts detrimentally to the transplant recipient
Transfer of tissue between species
One part of the body to another
Same species, different person
What does syngeneic mean?
What happens to a second skin graft on the same individual?
It is rejected faster than the first
What are the cells responsible for rejection?
What are the T cells reacting against?
Chromasome for HLA?
6 (short arm)
Where is class 1 HLA expressed?
– Universally expressed
– Cytoplasm derived proteins
– Presents Ag to CD8+ T cells
Where is class II HLA expressed?
– APC, inducible on other cells
– Extracellular derived proteins
– Presents Ag to CD4+ T cells
What are other markers we look for in transplantation?
What determines who gets a kidney?
This does not occur for other organs (eg lung)
What are the three types of rejection?
When can Antibody mediated rejection take place?
Can be any time (even months or years later)
What are the types of antibody responses in rejection?
Pre formed antibodies
- Blood group
- Blood transfusion
What is acute allograft rejection?
Foreign material travels to the lymph nodes where it can activate a T cell mediated response
What is chronic allograft rejection?
Can be both immunological and non-immunological
What is common to all chronic allograft rejection?
Intimal loss → loss of tubules
How do we prevent allograft rejection?
• Matching ABO antigens (not just expressed on erythrocytes)
• Matching MHC alleles
• Immunosuppressive drugs
How do we knock out the immune system?
Knock out the T cell
What drug is used to knock out the immune system?
Cyclosporin - selectively knocks out recently activated T cells
Also use steriods and azathioprine
What is a problem with using cyclosporin?
No longer effective at fighting viruses
What is the action of steroids?
Side effects of steroids?
Susceptibility to infection
What are the steps in the creation of a bioartificial lung?
Take donor lung
Decellularize with detergent
Establish acellular vasculature, airways and alveoli
Seed scaffold with epithelial and endothelial cells
Perfuse and ventilate in bioreactor