Transplantation

Types of Grafts

Homograft = self
Heterograft = same species
Xenograft = different species

 

Transplant considerations

  1. HLA matching:
    • Histocompatibility antigens defined by tissue typing - A, B, C, DP, DQ, DR (chromosome 6)
    • HLA Match essential: renal, pancreas
    • HLA Match non-essential: cardiac, hepatic
    • ABO blood group essential: renal, pancreatic, cardiac, hepatic (ie, all of them)
  2. Donor considerations
    • Established brainstem death
    • No sepsis
    • No maligancy (except primary brain)
    • No HIV, HBV
    • Not high risk : IVDU

Graft rejection

  1. Hyperacute rejection
    • recipient serum antibodies vs donor antigens (very bad news) - thrombosis, graft infarction within hours
    • treat by removal of graft
  2. Acute rejection
    • cell-mediated CD4 immunocytes (T-helper) within 3 months
    • Treated with steroids / immunosuppression
  3. Chronic rejection
    • Humoral / cell-mediated immune responses occurs months - years
    • Not treatable or reversible