Please enable JavaScript.
Coggle requires JavaScript to display documents.
Types of Rejection - Coggle Diagram
Types of Rejection
Hyperacute Rejection
Mechanism/ Characteristics
intravascular thrombosis
Necrosis of the vessel wall
mediated by preexisting antibodies (type II hypersensitivity)
Timing
within minutes to hours after host blood vessels are connected to graft vessels
Examples:
Acute Rejection
Timing
Begins after the first week of transplantation because it takes 7-10 days to activate T & B cells
Treatment
Immunosuppressive Drugs can delay acute rejection
Mechanism/ Characteristics
vascular/parenchymal injury mediated by T cells and
antibodies (type IV and II hypersensitivity)
Can be accelerated by a memory response
Activated T cells kill graft cells (CD8) or produce cytokines (CD4) that recruit & activate inflammatory cells
Antibody against HLA molecules (humoral response)
Chronic Rejection
Mechanism/ Characteristics
Fibrosis of the graft & arterial occlusion in vascularized graft
IFNg- producing CD4 (DTH/type IV hypersensitivity)
timing
within 6 months-1 year after transplantation.
treatment
refractory to most therapies-prevention
Procedures to prevent and treat graft rejection: Type 4