Fig 6 from Hricik, AJKD, © National Kidney Foundation.
AJKD recently published a Core Curriculum by Dr. Donald Hricik on transplant immunology and immunosuppression. The following questions based on the article will test your knowledge on this topic.
Post prepared by Dr. Vinay Nair, AJKD Blog Advisory Board member. For a PDF version of the questions & answers, please click here.
1. Which of the following immune responses is specific to transplantation?
Correct! Direct allorecognition occurs when passenger dendritic cells from donated organ travel to lymphoid tissue in the recipient resulting in lymphocyte activation. This can only take place in the setting of an organ transplant.
Activation of the innate immune response
Activation of the adaptive immune response
2. Which step is not required for T-cell activation?
Engagement of the T cell receptor with the MHC complex
Engagement of Toll-like receptors
Correct! Toll-like receptors are important in the innate immune response. Although the innate immune response does interact with the adaptive immune system, engagement of Toll-like receptors are not required for T cell activation.
3. Which of the following are not effector mechanisms of the immune response?
Binding of Fas on parenchymal cells with Fas ligand on T cells
Secretion of perforin and granzyme B by T cells
Interferon gamma production by NK cells
Correct!NK cells are effector cells that induce cell death by production of perforin and granzyme B, similar to CD-8 T cells. Interferon gamma production by NK cells promotes inflammation, but does not cause direct tissue injury.
4. All of the following have been used to treat rejection EXCEPT?
Correct! Corticosteroids are commonly used to treat rejection, and rabbit ATG is reserved for severe rejections. Rituximab has been used for antibody mediated rejection with variable success. Basiliximab has no efficacy in treating rejection.
5. All of the following are true about acute rejection EXCEPT?
Acute antibody-mediated rejection has a better prognosis than cellular rejection
Correct! Multiple studies reveal antibody-mediated rejection results in chronic rejection, transplant glomerulopathy, and pre-mature graft loss. In general, cellular rejection has a better prognosis.
Cellular rejection is more common than antibody-mediated rejection
Vascular involvement signifies a more severe variant of rejection
Hyperacute rejection occurs from a high titer of pre-formed anti-HLA antibodies
6. Which of the following induction agents is a monoclonal antibody against CD52?
Correct! Alemtuzumab is a monoclonal antibody directed against CD52 which is found on mature lymphocytes. It is FDA-approved to treat chronic lymphocytic leukemia and relapsing multiple sclerosis.
7. Which of the following induction agents is the most commonly used agent in the United States?
Correct! Although only basiliximab is approved by the FDA for induction in kidney transplantation, rabbit ATG is the most common induction agent in the USA.
8. Which of the following is INCORRECT about desensitization?
High-dose IVIg has been used to facilitate desensitization
Desensitization against anti-HLA antibodies results in better long-term outcome than desensitization against ABO antibodies
CorrectAlthough desensitization against ABO antigens may result in a high risk for early rejection, several studies have shown long term outcome to be comparable to ABO-compatible kidneys. Desensitization against HLA antibodies, even when successful, often leads to chronic rejection, transplant glomerulopathy, and early graft loss.
Plasmapheresis and low-dose IVIg have been used to facilitate desensitization against pre-formed HLA antibody
9. Early outcomes after kidney transplantation have improved dramatically, while long-term outcomes have improved to a much lesser extent. What is the predominant cause of a lack of improvement in long-term outcome?
Chronic antibody-mediated rejection
Correct! Recent studies reveal chronic antibody-mediated rejection to be the major cause of late graft failure.
Calcineurin inhibitor toxicity
Acute cell mediated rejection