Transplant Immunology and Rejection Flashcards

Which blood group compatibility rule is universally applied in solid organ transplantation?

Answer: ABO blood group compatibility between donor and recipient is required

ABO blood group compatibility is required in solid organ transplantation because ABO antigens are expressed on vascular endothelium and can trigger hyperacute rejection.

What is the significance of a positive cross-match in transplantation?

Answer: It indicates preformed antibodies that may cause rejection and is a contraindication

A positive cross-match indicates the recipient has preformed antibodies against donor antigens, which is generally a contraindication to transplantation due to high rejection risk.

Regulatory T cells (Tregs) play what role in transplant immunology?

Answer: They suppress immune responses and may promote graft tolerance

Regulatory T cells suppress immune responses against the graft and are being studied as a means to promote tolerance and reduce rejection.

Which class of HLA antigens is most important in kidney transplant matching?

Answer: HLA-DR

HLA-DR matching is considered the most clinically important in kidney transplantation due to its strong association with acute rejection rates and graft survival.

Which term describes the production of donor-specific antibodies after transplantation that were not present before the procedure?

Answer: De novo donor-specific antibody formation

De novo donor-specific antibody (DSA) formation refers to new antibodies produced after transplant targeting donor HLA antigens, associated with chronic antibody-mediated rejection.

Which immunosuppressant works by blocking the costimulatory signal required for T-cell activation?

Answer: Belatacept

Belatacept is a CTLA-4 Ig fusion protein that blocks the CD28-B7 costimulatory pathway, preventing full T-cell activation without antigen signal blockade.