Transplant

Question 1

Autograft

Answer 1

from self

Question 2

syngeneic graft

Answer 2

from identical twin or clone

Question 3

Allograft

Answer 3

from non-identical individual of same species

Question 4

Xenograft

Answer 4

From different species

Question 5

Pathogenesis Pre-existing recipient antibodies react to donor antigen (type II reaction), activate complement.

Features Widespread thrombosis of graft vessels–> ischemia/necrosis. Graft must be removed.

Id the type of rejection and onset

Answer 5

• Rejection type: Hyperacute
• Onset: with in minutes

Question 6

Pathogenesis Cellular: CTLs activated against donor MHCs. Humoral: similar to hyperacute, except antibodies develop after transplant.

Features Vasculitis of graft vessels with dense interstitial lymphocytic infiltrate. Prevent/reverse with immunosuppressants.

Id the rejection type and onset

Answer 6

• Rejection type: Acute
• Onset: Weeks to months

Question 7

Pathogenesis Recipient T cells percevie donor MHC as recipient MHC and react against donor antigens presented. Both cellular and humoral components.

Features Irreversible. T-cell and anti-body mediated damage.

Organ specific: Heart (atherosclerosis), Lungs (brocnhiolitis, obliterans), Liver (vanishing blue ducts). Kidney (vascular fibrosis, glomerulopathy).

Id the rejection type and onset

Answer 7

• Rejection: Chronic
• Onset: months to years

Question 8

Pathogenesis Grafted immunocompetent T cells proliferate in the immunocompromised host and reject host cells with foreign proteins –> severe organ dysfunction.

Features

• Maculopapular rash, jaundice, diarrhea, hepatosplenomegaly.
• Usually in bone marrow and liver transplants (rich in lymphocytes).
• Potentially beneficial in bone marrow transplant for leukemia (graft vs tumor effect)

Id the rejection type and onset

Answer 8

• Rejection type: Graft-vs-host disease
• Onset: varies