Transplant Immunology and Rejection Flashcards

Which type of rejection occurs within minutes to hours after transplantation and is caused by preformed antibodies?

Answer: Hyperacute rejection

Hyperacute rejection occurs within minutes to hours due to preformed recipient antibodies against donor antigens, causing immediate graft failure.

What is the primary role of HLA matching in solid organ transplantation?

Answer: To reduce the risk of immunologic rejection

HLA matching reduces the immunologic mismatch between donor and recipient, thereby lowering the risk of rejection.

Acute cellular rejection is primarily mediated by which immune cells?

Answer: T lymphocytes

Acute cellular rejection is primarily mediated by T lymphocytes that recognize donor antigens and mount an immune response against the graft.

Which immunologic test is performed before transplantation to detect preformed donor-specific antibodies?

Answer: Cross-match test

The cross-match test mixes recipient serum with donor lymphocytes to detect preformed donor-specific antibodies that could cause rejection.

Chronic allograft nephropathy is characterized by which pathological finding on biopsy?

Answer: Interstitial fibrosis and tubular atrophy

Chronic allograft nephropathy is characterized by interstitial fibrosis and tubular atrophy, reflecting cumulative immune and non-immune injury over time.

Panel Reactive Antibody (PRA) levels above what percentage indicate a highly sensitized transplant candidate?

Answer: 80%

A PRA of 80% or higher indicates a highly sensitized patient with many preformed antibodies, making it difficult to find a compatible donor.