21 BMD 430 Lecture 21 Flashcards

1. Which type of graft involves tissue transplanted between genetically different individuals of the same species?
A. Autograft
B. Allograft
C. Xenograft
D. Isograft

2. A heart transplant from a pig to a human is an example of:
A. Isograft
B. Autograft
C. Xenograft
D. Allograft

3. Alloantigens are best defined as:
A. Self-antigens recognized during autoimmune disease
B. Antigens that differ between individuals of the same species
C. Foreign molecules from pathogens
D. Carbohydrates on RBCs

4. Alloantibodies are antibodies produced against:
A. One’s own MHC
B. Antigens from a different species
C. A donor’s alloantigens
D. Bacterial carbohydrates

5. Histocompatibility refers to:
A. Matching of ABO antigens only
B. Degree of immunological compatibility between donor & recipient
C. Ability of RBCs to bind antibodies
D. Survival of the graft without immunosuppression only

6. MHC haplotypes are inherited:
A. From the father only
B. From the mother only
C. As one haplotype from each parent
D. Randomly from both parents without linkage

7. MHC matching is important because:
A. MHC is never recognized by T cells
B. MHC mismatch causes strong T-cell activation
C. MHC does not influence graft rejection
D. MHC is expressed only in RBCs

8. Blood transplantation is simpler than organ transplantation because:
A. RBCs lack MHC molecules
B. RBCs cannot activate complement
C. Cross-match testing is unnecessary
D. Antibodies do not bind RBCs

9. Anti-A and anti-B antibodies arise because:
A. The mother passes them to the baby
B. Exposure to commensal bacterial carbohydrates that mimic A/B antigens
C. MHC-II presentation of food antigens
D. Autoimmune response

10. The Rh factor refers to the presence of:
A. A/B antigens
B. MHC-I
C. The RhD antigen on RBCs
D. Complement receptors

11. A cross-match test detects:
A. Donor T cells
B. Recipient complement levels
C. Pre-formed antibodies in the recipient against donor RBCs
D. MHC compatibility

12. Hyperacute rejection is caused by:
A. T-cell activation against minor antigens
B. Pre-existing antibodies against donor ABO or MHC
C. Autoimmune antibodies
D. Slow chronic vascular changes

13. Hyperacute rejection occurs within:
A. Minutes to hours
B. Days to weeks
C. Months to years
D. Only after immunosuppression

14. Acute rejection is primarily mediated by:
A. Autoantibodies
B. Complement alone
C. Recipient T cells recognizing donor MHC
D. Innate macrophage activation only

15. Minor histocompatibility antigen mismatch leads to:
A. Rapid hyperacute rejection
B. No rejection
C. Slower, weaker T-cell responses
D. Antibody-mediated complement lysis only

16. Chronic rejection is characterized by:
A. Immediate thrombosis
B. Fibrosis and vessel narrowing over years
C. Massive cytokine storm within hours
D. Absence of immune activation

17. BMT is different from solid organ transplant because the graft:
A. Contains no immune cells
B. Is immunologically inactive
C. Contains active donor immune cells that can attack the host
D. Cannot cause rejection

18. Allogeneic transplantation involves:
A. Using the patient’s own stem cells
B. Using a genetically identical twin
C. Donor and recipient from the same species but genetically different
D. Donor cells from a different species

19. Myeloablative therapy is used to:
A. Boost donor immunity
B. Destroy recipient bone marrow before transplant
C. Increase MHC expression
D. Suppress RBC production only

20. Engraftment refers to:
A. Rejection of donor cells
B. Donor stem cells establishing in the recipient’s marrow
C. Removal of donor T cells
D. Development of hyperacute rejection

21. A chimera is a transplant recipient who:
A. Has no donor cells
B. Has mixed donor–recipient immune systems
C. Rejects all grafts
D. Has only donor DNA

22. GVHD occurs because:
A. Recipient T cells attack the donor graft
B. Donor T cells attack recipient tissues
C. Antibodies attack donor RBCs
D. Neutrophils destroy donor HSCs

23. GVHD most closely resembles which hypersensitivity type?
A. Type I
B. Type II
C. Type III
D. Type IV

24. H-Y antigens are significant because:
A. They prevent GVHD
B. They are MHC-II molecules
C. They are male-specific minor antigens that female donors may react to
D. They cause hyperacute rejection

25. GVHD can be beneficial because:
A. It suppresses the immune system completely
B. It provides a graft-versus-leukemia effect
C. It prevents chronic rejection
D. It eliminates the need for chemo

26. HLA matching is more important in BMT than solid organ transplant because:
A. BMT lacks immune cells
B. Donor T cells interact strongly with recipient tissues
C. RBCs express HLA
D. Minor antigens do not matter in BMT

27. General immunotherapies (e.g., steroids, calcineurin inhibitors):
A. Target very specific cytokines
B. Broadly suppress many immune pathways
C. Only suppress macrophages
D. Increase T-cell activation

28. Specific immunotherapies include:
A. Anti-IL-2 or anti-CD3 antibodies
B. Broad corticosteroids
C. Radiation therapy
D. Antibiotics

29. The purpose of immunosuppressive drugs is to:
A. Destroy the graft
B. Enhance MHC expression
C. Prevent rejection
D. Activate B cells

30. Immune-privileged sites include:
A. Skin
B. Eye, brain, testis, placenta
C. Liver and spleen
D. Lymph nodes

31. Combining HSC transplant with a solid organ transplant can:
A. Increase hyperacute rejection
B. Reset the immune system and promote tolerance to the organ
C. Prevent engraftment
D. Replace all recipient tissues entirely

A 45-year-old woman receives a kidney transplant. Within 20 minutes, the kidney becomes cyanotic and stops producing urine. Biopsy shows widespread thrombosis and complement deposition.

Question:
What caused this reaction and how could it have been prevented?

A 28-year-old man receives a liver transplant. Two weeks later, liver enzymes rise and biopsy reveals T-cell infiltration.

Question:
What type of rejection is occurring, and what is the immunological basis?

A corneal transplant is performed without MHC matching or systemic immunosuppression. No rejection occurs.

Question:
Why?

A 19-year-old patient undergoes allogeneic bone marrow transplantation for leukemia. Ten days later, she develops a maculopapular rash, severe diarrhea, and elevated liver enzymes.

Question:
What complication has occurred? What is the mechanism?