T-cell depleting antibodies — MCQs

A 34-year-old female medical professional who works for a non-governmental organization visits her primary care provider for a routine health check-up. She made a recent trip to Sub-Saharan Africa where she participated in a humanitarian medical project. Her medical history and physical examination are unremarkable. A chest radiograph and a tuberculin skin test (PPD) are ordered. The chest radiograph is performed at the side and the PPD reaction measures 12 mm after 72 hours. Which of the following mechanisms is involved in the skin test reaction?

Two weeks after undergoing allogeneic stem cell transplant for multiple myeloma, a 55-year-old man develops a severely pruritic rash, abdominal cramps, and profuse diarrhea. He appears lethargic. Physical examination shows yellow sclerae. There is a generalized maculopapular rash on his face, trunk, and lower extremities, and desquamation of both soles. His serum alanine aminotransferase is 115 U/L, serum aspartate aminotransferase is 97 U/L, and serum total bilirubin is 2.7 mg/dL. Which of the following is the most likely underlying cause of this patient's condition?

An investigator is studying the effect of different cytokines on the growth and differentiation of B cells. The investigator isolates a population of B cells from the germinal center of a lymph node. After exposure to a particular cytokine, these B cells begin to produce an antibody that prevents attachment of pathogens to mucous membranes but does not fix complement. Which of the following cytokines is most likely responsible for the observed changes in B-cell function?

A researcher is studying the circulating factors that are released when immune cells are exposed to antigens. Specifically, she is studying a population of CD2+ cells that have been activated acutely. In order to determine which factors are secreted by these cells, she cultures the cells in media and collects the used media from these plates after several days. She then purifies a small factor from this media and uses it to stimulate various immune cell types. She finds that this factor primarily seems to increase the growth and prolong the survival of other CD2+ cells. Which of the following is most likely the factor that was purified by this researcher?

A 61-year-old man presents to the emergency department with new-onset dizziness. He reports associated symptoms of confusion, headaches, and loss of coordination. The patient’s wife also mentions he has had recent frequent nosebleeds. Physical examination demonstrates a double vision. Routine blood work is significant for a slightly reduced platelet count. A noncontrast CT of the head is normal. A serum protein electrophoresis is performed and shows an elevated IgM spike. The consulting hematologist strongly suspects Waldenström’s macroglobulinemia. Which of the following is the best course of treatment for this patient?

A 35-year-old woman is admitted to the medical unit for worsening renal failure. Prior to admission, she was seen by her rheumatologist for a follow-up visit and was found to have significant proteinuria and hematuria on urinalysis and an elevated serum creatinine. She reports feeling ill and has noticed blood in her urine. She was diagnosed with systemic lupus erythematosus at the age of 22, and she is currently being treated with ibuprofen for joint pain and prednisone for acute flare-ups. Her blood pressure is 165/105 mmHg. Laboratory testing is remarkable for hypocomplementemia and an elevated anti-DNA antibody. A renal biopsy is performed, which demonstrates 65% glomerular involvement along with the affected glomeruli demonstrating endocapillary and extracapillary glomerulonephritis. In addition to glucocorticoid therapy, the medical team will add mycophenolate mofetil to her treatment regimen. Which of the following is the mechanism of action of mycophenolate mofetil?

A 6-year-old boy is brought to the physician because of headache, cough, runny nose, and a low-grade fever since waking up that morning. He has been healthy except for a urinary tract infection one week ago that has resolved with trimethoprim-sulfamethoxazole therapy. Both parents have a history of allergic rhinitis. His temperature is 37.8°C (100°F). Physical exam shows rhinorrhea and tenderness over the frontal and maxillary sinuses. There is cervical lymphadenopathy. Laboratory studies show: Hemoglobin 14.2 g/dL Leukocyte count 2,700/mm3 Segmented neutrophils 30% Bands 1% Eosinophils 4% Basophils 0% Lymphocytes 56% Monocytes 9% Platelet count 155,000/mm3 Which of the following is the most likely underlying cause of this patient's symptoms?

A 47-year-old woman presents to the physician with complaints of fatigue accompanied by symmetric pain, swelling, and stiffness in her wrists, fingers, knees, and other joints. She describes the stiffness as being particularly severe upon awakening, but gradually improves as she moves throughout her day. Her physician initially suggests that she take NSAIDs. However, after a few months of minimal symptomatic improvement, she is prescribed an immunosuppressive drug that has a mechanism of preventing IL-2 transcription. What is the main toxicity that the patient must be aware of with this particular class of drugs?

A 68-year-old man is brought to the emergency department 25 minutes after he was found shaking violently on the bathroom floor. His wife reports that he has become increasingly confused over the past 2 days and that he has been sleeping more than usual. He was started on chemotherapy 4 months ago for chronic lymphocytic leukemia. He is confused and oriented to person only. Neurological examination shows right-sided ptosis and diffuse hyperreflexia. An MRI of the brain shows disseminated, nonenhancing white matter lesions with no mass effect. A polymerase chain reaction assay of the cerebrospinal fluid confirms infection with a virus that has double-stranded, circular DNA. An antineoplastic drug with which of the following mechanisms of action is most likely responsible for this patient's current condition?

An otherwise healthy 13-year-old boy is brought to the physician because of asthma attacks that have been increasing in frequency and severity over the past 4 weeks. He was first diagnosed with asthma 6 months ago. Current medications include high-dose inhaled fluticasone and salmeterol daily, with additional albuterol as needed. He has required several courses of oral corticosteroids. A medication is added to his therapy regimen that results in downregulation of the high-affinity IgE receptor (FcεRI) on mast cells and basophils. Which of the following drugs was most likely added to the patient's medication regimen?