Immunomodulators

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Immunomodulators - Quiz

Questions and Answers
  • 1. 

    A 28-year-old woman was admitted to the hospital with fever, a malar butterfly erythema, arthralgia, intermittent pleuritic pain and oral ulcers. Her lab tests revealed the following: serum creatinine 5.2 mg/dL, BUN 35 mg/dL, and high serum level of antinuclear antibodies. Which of the following drugs was most likely included in the therapeutic management of this patient?

    • A.

      Infliximab

    • B.

      Prednisone

    • C.

      BCG vaccine

    • D.

      Interferon-beta-1b

    • E.

      Aldesleukin

    Correct Answer
    B. Prednisone
    Explanation
    The patient's symptoms and lab results are consistent with systemic lupus erythematosus (SLE), an autoimmune disease. Prednisone is a corticosteroid commonly used in the treatment of SLE to reduce inflammation and suppress the immune response. It helps to alleviate symptoms such as fever, erythema, arthralgia, and oral ulcers. Additionally, it can help to improve kidney function by reducing inflammation and preventing further damage. Infliximab, BCG vaccine, Interferon-beta-1b, and Aldesleukin are not typically used in the therapeutic management of SLE.

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  • 2. 

    A 32-year-old woman, who has been suffering from myasthenia gravis for four years, developed progressive dyspnea several days after an upper respiratory tract infection. Physical examination disclosed bilateral ptosis, bilateral facial weakness an diminished upper and lower motor strength. An IV edrophonium injection improved muscle strength. A serum assay for anti-acetylcholine receptor antibody was 4.8 (normal < 0.5). The appropriate treatment, promptly instituted, included a parenteral injection of prednisone. Which of the following statements best explains the most likely mechanism of action of the drug in this case?

    • A.

      Inhibition of plasma cholinesterase

    • B.

      Activation of Nm receptors

    • C.

      Stimulation of synthesis of interleukin 2

    • D.

      Inhibition of T cell activation and proliferation

    • E.

      Stimulation of synthesis of interleukin 1

    Correct Answer
    D. Inhibition of T cell activation and proliferation
    Explanation
    The most likely mechanism of action of prednisone in this case is the inhibition of T cell activation and proliferation. Prednisone is a corticosteroid that has immunosuppressive effects. In myasthenia gravis, T cells play a role in the autoimmune response that leads to the production of anti-acetylcholine receptor antibodies. By inhibiting T cell activation and proliferation, prednisone can help suppress the immune response and reduce the production of these antibodies, leading to an improvement in muscle strength.

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  • 3. 

    A 35-year-old man, who was scheduled for a heart transplant, received a triple immunosuppressive therapy just before surgery. Which of the following three drug combinations were most likely administered?

    • A.

      Azathioprine, prednisone, aldesleukin

    • B.

      Cyclosporine, azathioprine, prednisone

    • C.

      Prednisone, triamcinolone, cyclosporine

    • D.

      Aldesleukin, infliximab, etanercept

    • E.

      Infliximab, etanercept, triamcinolone

    Correct Answer
    B. Cyclosporine, azathioprine, prednisone
    Explanation
    The correct answer is Cyclosporine, azathioprine, prednisone. This combination of drugs is commonly used as immunosuppressive therapy in heart transplant patients. Cyclosporine is a calcineurin inhibitor that suppresses the immune response by inhibiting T-cell activation. Azathioprine is an antimetabolite that inhibits DNA synthesis and suppresses the proliferation of T and B cells. Prednisone is a corticosteroid that has anti-inflammatory and immunosuppressive effects. Together, these drugs help prevent rejection of the transplanted heart by suppressing the immune system.

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  • 4. 

    A 42-year-old man came to the clinic complaining of an extensive rash, white plaque-like lesions in his mouth, dry eyes, hyperpigmentation of the tissues surrounding the eyes, and diarrhea. Three months before the man, who was suffering from chronic myelogenous leukemia, underwent an allogeneic bone marrow transplantation from his sister and was successfully treated for his acute graft versus host disease. The patient had had no major health problems after that disease. Which of the following pairs of drugs were most likely included in the therapeutic treatment of this patient?

    • A.

      Prednisone and cyclosporine

    • B.

      Cyclosporine and erythromycin

    • C.

      Cyclophosphamide and doxorubicin

    • D.

      Vinblastine and prednisone

    • E.

      Doxorubicin and vinblastine

    Correct Answer
    A. Prednisone and cyclosporine
    Explanation
    The patient's symptoms, including rash, white plaque-like lesions in the mouth, dry eyes, hyperpigmentation, and diarrhea, are consistent with chronic graft versus host disease (GVHD) following bone marrow transplantation. Prednisone and cyclosporine are commonly used as immunosuppressive drugs to treat GVHD. Prednisone is a corticosteroid that suppresses the immune response, while cyclosporine is an immunosuppressive drug that inhibits T-cell activation. Therefore, the combination of prednisone and cyclosporine would be the most likely therapeutic treatment for this patient.

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  • 5. 

    A 32-year-old man suffering from extensive psoriasis resistant to topical agents and photochemotherapy, started an immunosuppressive treatment with oral cyclosporine. Which of the following cells represent the main site of action of the drug?

    • A.

      Macrophages

    • B.

      Dendritic cells

    • C.

      T-helper cells

    • D.

      Plasma cells

    • E.

      Natural killer cells

    Correct Answer
    C. T-helper cells
    Explanation
    Cyclosporine is an immunosuppressive drug that is commonly used to treat psoriasis. It works by inhibiting the activation and proliferation of T-helper cells, which play a key role in the immune response. By targeting T-helper cells, cyclosporine helps to reduce the inflammation and immune response associated with psoriasis. Macrophages, dendritic cells, plasma cells, and natural killer cells are not the main targets of cyclosporine, making T-helper cells the correct answer.

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  • 6. 

    A 45-year-old man, who had received an heart transplant one month ago, was in the hospital and scheduled for endomyocardial biopsy. The patients complained of a tingling sensation in his hands and peripheral edema. Significant blood test results were: potassium 6.1 mEq/L, creatinine 3.8 mg/dL, BUN 42 mg/dL Current medications included cyclosporine, prednisone, azathioprine, theophylline, diltiazem and famotidine. Biopsy results indicated no acute rejection. If the lab results were drug related, which of the following was the most likely causative agent?

    • A.

      Prednisone

    • B.

      Cyclosporine

    • C.

      Azathioprine

    • D.

      Theophylline

    • E.

      Diltiazem

    Correct Answer
    B. Cyclosporine
    Explanation
    The most likely causative agent for the patient's tingling sensation in his hands and peripheral edema is cyclosporine. Cyclosporine is an immunosuppressant medication commonly used in organ transplant recipients to prevent rejection. However, it can cause side effects such as hyperkalemia (high potassium levels), renal dysfunction (elevated creatinine and BUN levels), and peripheral edema. These symptoms are consistent with the patient's lab results and are known adverse effects of cyclosporine.

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  • 7. 

    A 33-year old man with an end stage renal disease underwent a kidney transplant. The therapeutic management of the patient included an IV injection of azathioprine just before surgery. Which of the following statements best explains the most likely mechanism of action of the drug in this case?

    • A.

      Blockade of receptors of TNF-alpha

    • B.

      Inhibition of clonal expansion of T and B lymphocytes

    • C.

      Inhibition of antigen presentation by dendritic cells

    • D.

      Stimulation of genetic expression of interleukin 2

    • E.

      Stimulation of macrophage phagocytic activity

    Correct Answer
    B. Inhibition of clonal expansion of T and B lymphocytes
    Explanation
    Azathioprine is an immunosuppressive drug commonly used in organ transplantation to prevent rejection. It works by inhibiting the clonal expansion of T and B lymphocytes, which are key players in the immune response. By suppressing the proliferation of these cells, azathioprine helps to dampen the immune response and reduce the risk of rejection of the transplanted kidney. This mechanism of action makes it an effective therapeutic option in patients undergoing organ transplantation.

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  • 8. 

    A 32-year-old man, who underwent renal transplant, showed signs of acute allograft rejection which was resistant to corticosteroid treatment. He was treated with muromonab CD3 that was able to reverse the rejection. Which of the following statements best explains the molecular mechanism of action of the drug in this case?

    • A.

      It inhibits antibody formation by plasma cells

    • B.

      It inhibits several enzymes involved in purine metabolism

    • C.

      It inhibits calcineurin enzyme in T cell cytoplasm

    • D.

      It stimulates the synthesis of interleukin-1 in T cells

    • E.

      It neutralize a surface protein receptor complex in T cells

    Correct Answer
    E. It neutralize a surface protein receptor complex in T cells
    Explanation
    The correct answer is "It neutralizes a surface protein receptor complex in T cells." Muromonab CD3 is a monoclonal antibody that specifically targets and binds to the CD3 receptor complex on the surface of T cells. By binding to this receptor complex, the drug prevents T cell activation and subsequent immune response, thereby reversing the acute allograft rejection. This mechanism of action is different from the other options, which do not specifically target T cell receptors or surface protein receptor complexes.

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  • 9. 

    A 27-year-old primipara delivered a baby boy at term. The woman was Rho(D) negative and her husband was Rho(D) positive. The woman received an IV injection of Rho(D) immune globulin just after the delivery. Which of the following statements best explains the mechanism of action of the Rho(D) immune globulin?

    • A.

      It prevents placental crossing of Rho(D) positive erythrocytes in subsequent pregnancies

    • B.

      It blocks the production of maternal antibodies against Rho(D) positive erythrocytes

    • C.

      It prevents the hemolytic disease of the mother in subsequent pregnancies

    • D.

      It blocks the production of fetal Rho(D) positive erythrocytes in subsequent pregnancies

    • E.

      It prevents the placental crossing of fetal Rho(D) antibodies in subsequent pregnancies

    Correct Answer
    B. It blocks the production of maternal antibodies against Rho(D) positive erythrocytes
    Explanation
    Rho(D) immune globulin works by blocking the production of maternal antibodies against Rho(D) positive erythrocytes. When a Rho(D) negative woman carries a Rho(D) positive fetus, there is a risk of sensitization, where the mother's immune system produces antibodies against the baby's blood type. Rho(D) immune globulin prevents this sensitization by binding to and blocking the Rho(D) positive antigens on fetal erythrocytes, preventing the mother from producing antibodies against them. This helps to prevent hemolytic disease of the newborn in subsequent pregnancies.

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  • 10. 

    A 42-year-old woman undergoing heart transplant received mycophenolate mofetil, cyclosporine and prednisone before surgery. Which of the following statements best explains why mycophenolate mofetil is currently substituted for azathioprine to prevent rejection in solid organ transplantation ?

    • A.

      Its immunosuppressant activity is definitely superior to that of azathioprine

    • B.

      It has significantly less adverse effects than azathioprine

    • C.

      It has drastically reduced the risk of graft versus host disease

    • D.

      It selectively inhibits macrophage-mediated production of several interleukins

    • E.

      It selectively inhibits antigen recognition by antigen presenting cells

    Correct Answer
    B. It has significantly less adverse effects than azathioprine
    Explanation
    Mycophenolate mofetil is currently substituted for azathioprine in solid organ transplantation because it has significantly less adverse effects than azathioprine. This means that patients who receive mycophenolate mofetil are less likely to experience negative side effects compared to those who receive azathioprine. By using mycophenolate mofetil, the risk of complications and adverse reactions can be minimized, improving the overall outcome of the transplant procedure.

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  • 11. 

    A 46-year-old man came to his doctor complaining that his joints were very painful.  He had been taking NSAIDs and then glucocorticosteroids for 2 -3 years, and they were no longer working.  Investigations   showed that he had a high erythrocyte sedimentation rate and a low hematocrit, synovial leukocytosis, and progressive loss of joint mobility and function.   He was prescribed a two drug treatment.  One drug was a biological agent which targeted an inflammatory cytokine, produced by activated macrophages and T-cells in inflamed joints.  The second drug has anti-inflammatory activity independent of its cytotoxic actions.  It is often given with a folate supplement.  It is known to slow joint erosion, and remains efficacious longer than other Disease-Modifying Antirheumatic Drugs. Which of the following pairs of drugs fulfill the criteria for the drug regimen recommended for this patient?

    • A.

      Aldesleukin and cyclophosphamide

    • B.

      Interferon alpha and cyclosporine

    • C.

      Infliximab and methotrexate

    • D.

      Rituxumab and methotrexate

    Correct Answer
    C. Infliximab and methotrexate
    Explanation
    Infliximab is a biological agent that targets an inflammatory cytokine produced by activated macrophages and T-cells in inflamed joints. This aligns with the patient's symptoms and the high erythrocyte sedimentation rate, indicating inflammation. Methotrexate is an anti-inflammatory drug that has independent cytotoxic actions. It is often given with a folate supplement and is known to slow joint erosion. Both drugs fulfill the criteria of targeting inflammation and slowing joint erosion, making them suitable for the recommended drug regimen for this patient.

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  • 12. 

    A patient who received a renal transplant six months previously, is being maintained on methylprednisolone, sirolimus, and mycophenolate mofetil.  A week ago he was brought to the ER with a fever, pain over the graft, and he reported a significant decrease in urine volume.  A panel of tests and a renal biopsy were ordered. The results of tests on his blood revealed creatinine levels of 3.8/dL (normal 0.5-1.2mg/dL), BUN 56mg/dL,(normal 5-20) ; the BUN /creatinine ration is 14/1(normal 10/1).  Which of the following, best reflects the most appropriate modification to the current course of therapy for this patient?

    • A.

      Add muromonab CD3

    • B.

      Add a diuretic

    • C.

      Add etanercept

    • D.

      Substitute cyclosporine for sirolimus

    • E.

      Add azathioprine

    Correct Answer
    A. Add muromonab CD3
    Explanation
    Muromonab-CD3 is an immunosuppressant drug given to reduce acute rejection in patients with organ transplants. It is a monoclonal antibody (mouse origin) targeted at the CD3 receptor, a membrane protein on the surface of T cells

    Muromonab-CD3 is approved for the therapy of acute, glucocorticoid resistant rejection of allogeneic renal, heart and liver transplants. Unlike the monoclonal antibodies basiliximab and daclizumab, it is not approved for prophylaxis of transplant rejection.
    It has also been investigated for use in treating T-cell acute lymphoblastic leukemia

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  • 13. 

    The diagram below illustrates the importance of purine synthesis  in the  cell cycle.  What is the best explanation of the immunosuppressive actions of mycophenolate  in the prevention of  renal graft rejection?

    • A.

      Renal tubular epithelial cells are targeted and sent into G0 phase where they are protected from immune attack

    • B.

      Grafted cells are prevented from producing cell surface antigens as their metabolism slows down

    • C.

      B cells cannot produce antibodies so the graft is protected from attack

    • D.

      Purine metabolism in mature T&B cell is targeted, T-cell proliferation is prevented and the rejection process is stopped

    Correct Answer
    D. Purine metabolism in mature T&B cell is targeted, T-cell proliferation is prevented and the rejection process is stopped
    Explanation
    Mycophenolate targets the purine metabolism in mature T&B cells, which leads to the prevention of T-cell proliferation. This action stops the rejection process of the renal graft. By inhibiting purine synthesis, mycophenolate suppresses the immune response by reducing the production of nucleotides required for cell division and proliferation. This ultimately prevents the activation and expansion of T-cells, which play a crucial role in graft rejection.

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  • 14. 

    Cancer chemotherapy, bone marrow transplantation, and HIV, cause profound depression of cell numbers in the bone marrow .  Which cell counts increase as a result of the actions of Filgrastim and Sargramostim?

    • A.

      Lymphocytes

    • B.

      Neutrophils

    • C.

      Stem cells

    • D.

      Dendritic cells

    • E.

      Macrophages

    Correct Answer
    B. Neutrophils
    Explanation
    Chemotherapy, bone marrow transplantation, and HIV can lead to a decrease in cell numbers in the bone marrow, including neutrophils. Filgrastim and Sargramostim are drugs that stimulate the production of neutrophils, therefore increasing their count. These drugs are commonly used to treat neutropenia, a condition characterized by low levels of neutrophils in the blood.

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  • 15. 

    A 28 year old male patient is given cyclosporine and prednisone prior to receiving a kidney transplant.Which immunocompetant cells are prevented from mounting an immune response?

    • A.

      B lymphocytes

    • B.

      Cytotoxic B lymphocytes

    • C.

      Dendritic cells

    • D.

      Th2 lymphocytes

    • E.

      Th1 lymphocytes

    Correct Answer
    E. Th1 lymphocytes
    Explanation
    Cyclosporine and prednisone are immunosuppressive drugs commonly used in organ transplantation to prevent rejection. Cyclosporine specifically targets Th1 lymphocytes, which are a type of T lymphocyte involved in cell-mediated immunity. By inhibiting the activity of Th1 lymphocytes, the drugs prevent these cells from mounting an immune response against the transplanted kidney, reducing the risk of rejection. B lymphocytes, cytotoxic B lymphocytes, dendritic cells, and Th2 lymphocytes are not specifically targeted by these drugs in the context of organ transplantation.

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  • 16. 

    Rapidly dividing B&T-lymphocytes cannot utilise the salvage pathway for purine synthesis. Which immunosuppressive drug prolongs graft survival by specifically inhibiting the synthesis of a precursor of nucleic acid synthesis?

    • A.

      Azathioprine

    • B.

      Mycophenolate mofetil

    • C.

      Cyclosporine

    • D.

      Muromonab CD3

    • E.

      Sirolimus

    Correct Answer
    B. Mycophenolate mofetil
    Explanation
    Rapidly dividing B&T-lymphocytes cannot utilize the salvage pathway for purine synthesis, which means they rely on de novo purine synthesis. Mycophenolate mofetil specifically inhibits the enzyme inosine monophosphate dehydrogenase (IMPDH), which is involved in de novo purine synthesis. By inhibiting IMPDH, mycophenolate mofetil prevents the synthesis of guanosine nucleotides, ultimately inhibiting the proliferation of lymphocytes. This immunosuppressive effect helps to prolong graft survival by suppressing the immune response.

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  • 17. 

    A hospitalised patient developed anorexia, acute abdominal discomfort, and severe headache. The previous week she had received a liver transplant together with appropriate immunosuppressants . Her laboratory results showed an increase in serum transaminases and bilirubin,   confirming a diagnosis of moderate graft rejection.  Her medications were switched to IV methyl prednisolone and a drug which disrupts both activated and non-activated T lymphocyte functions. Which of the following drugs has this profile?

    • A.

      Sirolimus

    • B.

      Azathioprine

    • C.

      Mycophenolate mofetil

    • D.

      Muromonab CD3

    • E.

      Methotrexate

    Correct Answer
    D. Muromonab CD3
    Explanation
    Muromonab CD3 is the correct answer because it is a drug that disrupts both activated and non-activated T lymphocyte functions. This drug is used to prevent acute graft rejection in organ transplant patients. In this case, the patient's symptoms and laboratory results indicate moderate graft rejection, so switching to Muromonab CD3 would be an appropriate treatment choice.

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  • 18. 

    A hospitalised patient, who developed serious hypotension, was diagnosed with capillary leak syndrome and pulmonary edema. He was receiving antimalignant chemotherapy, and adjunctively, a recombinant form of an endogenous cytokine, as treatment for his metastatic renal cell carcinoma .Which of the following drugs most likely caused his current problems?

    • A.

      Oprelvekin

    • B.

      Aldesleukin

    • C.

      Interferon- alpha2A

    • D.

      Interleukin-1

    • E.

      Sargramostim

    Correct Answer
    B. Aldesleukin
    Explanation
    1. Aldesleukin
    A recombinent form of Interleukin 2 that promotes lymphoid cell differentiation into cytotoxic cells, and activates natural killer cells (NK's)
    USES --- As an adjunct in metastatic renal cell carcinoma.
    Recently approved for treatment of metastatic melanoma.

    Treatment is associated with serious cardiovascular toxicity resulting from’ capillary leak syndrome’. This involves loss of vascular tone, leakage of plasma proteins and fluid into the extravascular space, which may result in hypotension, reduced organ perfusion and even death.

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  • 19. 

    A 47-year- old woman with choriocarcinoma is treated with very high doses of methotrexate (MTX).Which of following drugs is given to limit the toxic effects of this regimen on normal host cells?

    • A.

      Deferoxamine

    • B.

      Leucovorin

    • C.

      N-acetyl cysteine

    • D.

      Penicillamine

    Correct Answer
    B. Leucovorin
    Explanation
    Folinic acid or leucovorin generally administered as calcium or sodium folinate (or leucovorin calcium/sodium), is an adjuvant used in cancer chemotherapy involving the drug methotrexate. It is also used in synergistic combination with the chemotherapy agent 5-fluorouracil.
    MOA:
    Folinic acid is a 5-formyl derivative of tetrahydrofolic acid. It is readily converted to other reduced folic acid derivatives (e.g., tetrahydrofolate), and, thus, has vitamin activity that is equivalent to that of folic acid. However, since it does not require the action of dihydrofolate reductase for its conversion, its function as a vitamin is unaffected by inhibition of this enzyme by drugs such as methotrexate.

    Folinic acid, therefore, allows for some purine/pyrimidine synthesis to occur in the presence of dihydrofolate reductase inhibition, so that some normal DNA replication and RNA transcription processes can proceed.

    Folinic acid is administered at the appropriate time following methotrexate as part of a total chemotherapeutic plan, where it may "rescue" bone marrow and gastrointestinal mucosa cells from methotrexate. There is no apparent effect on preexisting methotrexate-induced nephrotoxicity.

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  • 20. 

    A 35 year old man has been receiving mycophenolate mofetil prophylactically for renal transplant rejection.  This drugs acts by inhibiting:

    • A.

      The induction of proinflammatory cytokines such as IL-2.

    • B.

      The enzyme mammalian kinase in the G1- S phase.

    • C.

      Inosine monophosphate dehydrogenase in the guanosine nucleotide pathway

    • D.

      The binding of TNF alfa to its receptors.

    Correct Answer
    C. Inosine monophosphate dehydrogenase in the guanosine nucleotide pathway
    Explanation
    Mycophenolate mofetil is known to inhibit inosine monophosphate dehydrogenase (IMPDH) in the guanosine nucleotide pathway. IMPDH is an enzyme involved in the synthesis of guanosine nucleotides, which are essential for DNA and RNA synthesis. By inhibiting IMPDH, mycophenolate mofetil prevents the proliferation of lymphocytes, which are involved in transplant rejection. This inhibition ultimately leads to immunosuppression and helps prevent rejection of the transplanted kidney.

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  • 21. 

    Levamisole as adjunctive therapy.  This drug acts as follows.

    • A.

      It stimulates maturation/proliferation of T cells

    • B.

      It stimulates committed erythroid precursors

    • C.

      It is a non-lineage- specific hematopoietic agent

    • D.

      It inhibits TNF alpha production

    Correct Answer
    A. It stimulates maturation/proliferation of T cells
    Explanation
    Levamisole Antiparasitic drug that stimulates maturation/ proliferation of T cells.
    It enhances T-cell mediated immune responses

    Uses:
    Adjunctive treatment together with 5- fluorouracil and leucovorin, (whose actions it potentiates) after surgical resection in patients with Dukes Stage C colon cancer.
    Has been used in the treatment of Nephrotic Syndrome(not an FDA approved indication)

    Adverse effects:
    -Neutropenia, anemia, thrombocytopenia and agranulocytosis,.
    -Encephalopathy associated with demyelination.

    Not marketed in the US now because of the agranulocytosis However, thiscancer is very difficult to treat so this drug may still be used with permission.

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  • 22. 

    A 38 year old woman on treatment with methotrexate for severe chronic arthritis was give leucovorin as a rescue agent for her anemia. With regard to the mechanism of action of leucovorin, which of the following is the most correct statement?

    • A.

      Inside the cell the drug is metabolized to other reduced folate cofactors such as methyl-THF and methylene-THF which assist recovery of the blood cells

    • B.

      Inside the cell the drug is metabolized to dihydrofolate which assists recovery of the blood cells

    • C.

      It is a folate analog and can thus substitute for folate, which assists in recovery of the blood cells

    • D.

      It is a precursor of tetrahydrofolate and can thus increase folate levels leading to recovery of the blood cells

    Correct Answer
    A. Inside the cell the drug is metabolized to other reduced folate cofactors such as methyl-THF and methylene-THF which assist recovery of the blood cells
    Explanation
    Folinic acid (LEUCOVORIN) is a 5-formyl derivative of tetrahydrofolic acid. It is readily converted to other reduced folic acid derivatives (e.g., tetrahydrofolate), and, thus, has vitamin activity that is equivalent to that of folic acid. However, since it does not require the action of dihydrofolate reductase for its conversion, its function as a vitamin is unaffected by inhibition of this enzyme by drugs such as methotrexate.

    Folinic acid, therefore, allows for some purine/pyrimidine synthesis to occur in the presence of dihydrofolate reductase inhibition, so that some normal DNA replication and RNA transcription processes can proceed.

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  • 23. 

    A 60 year old woman is diagnosed with a malignant lymphoma.  Ten years ago, she was diagnosed with a disease that caused her eyes and mouth to be dry.  Physical examination reveals a woman in no acute distress with lymphadenopathy.  Laboratory data is significant for a positive antinuclear antibody test.  Which of the following antibodies is most likely positive in this case?

    • A.

      Anti-double stranded DNA

    • B.

      Anti –Scl-70

    • C.

      Anti-centromere

    • D.

      Anti-nuclear RNP

    Correct Answer
    B. Anti –Scl-70
    Explanation
    The correct answer is Anti-Scl-70. This is because the patient's history of dry eyes and mouth, along with the positive antinuclear antibody test, suggests that she may have Sjögren's syndrome. Sjögren's syndrome is commonly associated with autoimmune diseases, such as systemic sclerosis (scleroderma), which is characterized by the presence of Anti-Scl-70 antibodies. Therefore, it is likely that the patient in this case has positive Anti-Scl-70 antibodies.

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  • Mar 21, 2023
    Quiz Edited by
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  • Jun 18, 2012
    Quiz Created by
    Chachelly
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