Host Quizzes
Which of the following amino acids most likely enables the sugar attachments in the N-linked glycoproteins? A.Asn B.Cys C.Gly D.Thr E.Ser
A
What suceptibility profile would you expect to see in this patient? Select all that apply. A.Severe/ recurrent bacterial infections B.Severe/ recurrent fungal infections C.Severe/ recurrent viral infections D.Severe/ recurrent parasitic infections
A and B
A defect in which of the following molecules might prevent the occurance of sepsis in response to gram(-) bacterial infection? A. MyD88 B. IFR3 C. IRAK-4 D. IRF7
A, C
A 20-year-old man has been experiencing painful urination for 7 days. Cultures are positive for Gram (-) Neisseria gonorrheae. In addition, numerous neutrophils are present in a smear of the exudate sampled from his urethral opening. Which of the following inflammatory mediators is most likely promoting the recruitment of neutrophils into the affected tissues as well as directly mediating the destruction of the bacteria? A. Bradykinin B. Complement components C. C-reactive protein D. Histamine E. Prostaglandin
B
A blood sample is assessed by flow cytometry to determine the relative frequency of different WBCs circulating in the peripheral blood of a patient. The results indicate that there is an absolute absence of CD3+ cells present in the blood. Based on this, what type of immune cell is deficient in this patient? A.B cells B.T cells C.NK cells D.Monocytes E.Neutrophils
B
Which of the following leukocyte types is depicted in this photomicrograph? A. Basophil B. Eosinophil C. Monocyte D. Macrophage E. Neutrophil
B
Analysis of this plasma reveals elevated amounts of circulating IL-1, IL-6 and TNF-α. The elevation of these cytokines is most likely due to which of the following events? A.Activation of NK cells by local secretion of IL-12 B.Activation of neutrophils by PRR stimulation C.Activation of macrophages by PRR stimulation D.Release of inflammatory mediators by innate immune cells E.Acute phase response in the liver
C
Expression of which of the following factors will be induced by engagement of TLR3 by its ligand? A.IL-1 B.IL-2 C.IFN-beta D.IFN-gamma E.TNF-alpha
C
A 7 year-old-boy with a peanut allergy accidentally consumes a peanut containing chocolate bar after Halloween trick-or-treating. He begins to experience an acute allergic reaction termed anaphylaxis. Which of the following immune cells is most likely causing his allergic reaction? A. Eosinophils B. Macrophages C. Neutrophils D. Mast cells E. NK cells
D
A 7-year-old male child presents at the Emergency Department with fever, cough, dyspnea (shortness of breath), and loss of smell. Swabbing of his oropharynx is positive for COVID-19 using real-time PCR analysis. Which of the following cytokines will offer him the most protection early on in during the viral infection? A. IL-1 and IL-6 B. IL-10 and TGF-beta C. IL-12 and IL-12 D. IFN alpha and IFN beta
D
Which of the following immune cells must complete their development in the thymus? A. B cells B. Eosinophils C. Mast cells D. Monocytes E. T cells
E
A 22-year-old female patient has contracted "strep throat" while living at her college dorm. Which of the following inflammatory cytokines produced by stimulated macrophages and monocytes present in her tonsillar tissue is responsible for causing her fever? A. IL-1 B. IL-8 C. IL-12 D. IL-15 E. IL-18
A
A three-month-old male infant is brought to the pediatrician due recurrent bacterial skin infections that do not resolve and do not form pus. Physical exam reveals infection of the umbilical cord stump (omphalitis). FACS analysis of his peripheral blood cells reveals neutrophilia. A defect in what process most likely underlies this presumptive immune disorder? A.Adhesion of neutrophils to the vascular endothelium B.Diapedesis of neutrophils and and migration in the tissue C.Activation of LFA integrins on leukocytes by Cxcl8 D.Intracellular killing
A
Chemotaxis of DCs to the draining lymph node occurs in response to the chemokine CCL21. The receptor for CCL21 belongs to which of following receptor families? A. G protein-coupled receptor family B. Immunoglobin-like recetpor family C. TGF recetpor family D. TNF recetpor family E. Type I and Type II receptor families (hematopoietin and IFN)
A
Hereditary lysosomal storage diseases mucopolysaccharidoses (MPS) are most likely caused by: A.Defects in degradation of glycosaminoglycans B.Defects in the targeting of enzymes to lysosomes C.An increased rate of synthesis of the carbohydrate component of proteoglycans D.An insufficient rate of synthesis of proteolytic enzymes E.The synthesis of abnormally small amounts of core proteins
A
Macrophages that are activated at the site of infection release various factors shortly after pattern recognition receptor engagement. Which of the following soluble factors that they release induces expression of ICAM-1 and ICAM-2 adhesion molecules on the vascular endothelium, making the blood vessel walls "sticky" for leukocytes so that they can bind and diapedesis into the tissue? A.IL-1 B.IL-6 C.IL-8 D.Prostaglandin E.Nitric oxide
A
Pathogen recognition receptors (PRRs) are critical to the function of the innate immune system. Which of the following statements correctly describes PRRs. A. They can recognize PAMPs from pathogens and DAMPs from damaged tissues B. They are expressed from genes that undergo somatic recombination C. They bind highly specific antigenic sequences derived from pathogens D. They are found only on the surface of immune cells E. They signal for apoptosis
A
Which of the following complement receptors is involved in the clean-up of immune complexes (I:C)? A. Complement receptor 1 (CR1) B. Complement receptor 2 (CR2) C. Complement receptor 3 (CR3) D. Complement receptor 4 (CR4) E. Complement receptor 5 (CR5)
A
A 48-year-old female is infected with a strain of influenza A virus that was not covered by the vaccine she received this year. The virus begins to replicate in her respiratory tract. Which of the following pattern recognition receptors (PRRs) will most likely become engaged by the replicating virus? A. TLR7 B. CD14 C. TLR3 D. TLR4 E. Inflammasome
A and C
How could you be ascertain that the patient is having a reaction to killed organism and not an adverse reaction caused by a penicillin allergy; both exhibit a similar-appearing rash? A.timing of reaction B.fever /absence of fever C.measure tryptase levels in the plasma D.hypotension / no hypotension
A, B, C
A 34-year old man is infected with Gram(-) bacteria and mounts an inflammatory response to the pathogen. Which of the following factors will drive NF-Kappab activation in this patient, leading to sepsis? A.TLR4 B.IL-1 C.TLR3 D. TNF-alpha
A, B, D
A 34-year-old female presents to her primary care physician's office with a 5-month history of bilateral swelling in her hands and wrists. She indicates that she experiences morning stiffness that lasts for a few hours and then improves. On exam, there is tenderness to palpation and apparent swelling of the proximal interphalangeal joints and metacarpophalangeal joints which on radiology, reveals as erosions at the affected joints. Blood tests reveal significantly elevated C-RP levels compared to controls. Further testing confirms that the patient has Rheumatoid arthritis. The cytokine(s) most likely responsible for both her symptoms and test results is/are: A. IL-1 B. IL-6 C. IL-10 D. IFN-alpha E. TNF-alpha
A, B, E
A 22-year-old female patient has contracted strep throat while living at her college dorm. Which of the following cytokines produced by bacteria-activated macrophages present in her tonsillar tissue is responsible for causing her fever? Select all that applies. A. IL-1 B. IL-8 C. IL-12 D. TNF-alpha E. IL-6
A. IL-1; B. IL-8; D. TNF-alpha
A 28-year-old man is being treated for primary syphilis with penicillin. 6 hours after starting his antibiotic regime, he begins to manifest a macular rash over most of his body, chills, fever, hypotension, and tachycardia. Which of the following statements most likely accounts for his reaction to treatment? A.Exotoxin release B.Endotoxin-like release C.Direct cytopathic effects D.Drug allergy E.Neutrophil-mediated tissue damage
B
A 48-year-old male presents at a primary care clinic with a recent history of anemia and hemolysis, as evidenced by hemoglobineria, especially evident in his morning voiding. His past medical history is unremarkable. He appears otherwise healthy. A blood sample is taken and flow cytometric analysis is performed on his peripheral blood cells. Based on this information, which of the following complement components would most likely be deficient in this patient, leading to the hemolysis? A. C1Inh B. CD55 and CD59 C. C1, C2, and/or C4 D. C5, C6, C7, C8, and/or C9 E. Factor H and Factor I
B
A 5-year-old male presents at the medical office. He has a longitudinal history of recurrent upper and lower respiratory infections caused by Haemophilus influenza and Streptococcus pneumonia. He has a prominent rash on his face and complains of painful joints. Serum is collected and assessed using the CH50 and AH50 test methods. Assuming that your prediction is correct regarding the C' deficiency that this patient has, what do you anticipate the tests results to include? A. CH50 will be normal, AH50 will be abnormal B. CH50 will be abnormal, AH50 will be normal C. Both CH50 and AH50 will be normal D. Both CH50 and AH50 will be abnormal
B
As his sepsis evolves, his monocytes and macrophages will produce anti-inflammatory cytokines as a compensatory response to excess inflammation. The major anti-inflammatory cytokine produced in this scenario is: A.IL-4 B.IL-10 C.IL-12 D.IL-13 E.IL-15
B
Deficiency of the which of the following enzymes is most likely responsible for Sly syndrome (mucopolysaccharidosis type IV)? A. α- L- Iduronidase B. β- Glucuronidase C. Heparan sulfatase D. Iduronate sulfatase E. N-acetylglucosamine-1-phosphotransferase
B
Mast cells in the lamina propria of the mucosal tissues begins to degranulate in response to contact with an allergen. What factor released by the mast cells will effect vasodilation, broncho-constriction, capillary permability, and urticaria? A. Nitric oxide B. Histamine C. Heparin D. Tryptase E. Prostaglandin
B
Migration and diapedesis of leukocytes, including neutrophils, across the vascular endothelium into affected tissues involves which of the following interactions? A.CCL21 in fluid phase binding to CCR7 on the neutrophil B.ICAM-1 and ICAM-2 on the endothelium binding to CR3 and CR4 on the neutrophil C.LFA-1 on endothelial cells binding to ICAM-1 and ICAM-2 on the neutrophil D.CCL5 binding to CCR5 on the neutrophil E.E selectin on the neutrophil binding to sialyl-Lewis X antigen on the endothelium
B
Mutations leading to constitutive inflammasome activity are seen in various auto-inflammatory diseases such as the periodic fever syndromes. The activity of which cytokine is most likely to be directly upregulated as a result of constitutive inflammasome activity? A. IL-1 alpha B. IL-1 beta C. IFN-alpha D. IFN-beta E. IFN-gamma
B
Once it has been phagocytosed, a pathogen must be killed inside the phagolysome or it will continue to infect the host. What enzyme is critically responsible for the formation of a superoxide (O2*) radical within the phagolysosome? A. Superoxide dismutase B. NADPH oxidase C. Myeloperoxidase D. Myeloid oxidase E. Superoxide dehydrogenase
B
The patient is treated with Remicade (Infliximab) to slow down the disease progression. What is the mechanism of action of Remicade (use the WWW)? A. Directly blocks the activation of osteoclasts B. Directly binds to the target cytokine so that it cannot bind its receptor C. Promotes the secretion of IL-10 from macrophages, attenuating the inflammatory response D. Directly blocks the target cytokine by binding to its receptor
B
What signaling factors are required for TLR4 to respond to LPS? A.JAK, STATs B.MyD88, IRAK, NF-κB C.IRF3 and IRF7 D.RAS/MAPK/ AP-1 E.SMAD2, SMAD3, SMAD4
B
Which cell is principally responsible for causing his symptoms and signs of his Jarisch-Herxheimer reaction? A.Dendritic cell B.Macrophage C.Mast cell D.Neutrophil E.NK cells
B
Which of the following complement component(s) participate(s) in the initiation of the classical complement cascade? A. C5 convertase B. C1q, C1r, C1s C. Hydrolysis of C3 D. Factor B and Factor D E. Mannose-binding protein
B
Which of the following down-stream signaling events is most likely to occur following stimulation of a prototypic growth factor receptor such as VEGF Receptor? A. Activation of JAK/STAT B. Activation of RAS/MAPK pathway C. Activation of NF-κB D. Activation of NFAT E. Activation of SMADs
B
Which of the following factors contributes to vasodilation and therefore erythema in the acute local inflammatory response? A.CCL-18, 19 and 21 B.Histamine, NO and bradykinin C.IFN-alpha and C3a, C5a D.IL-6 and IL-8 E.IL-10 and TGF-beta
B
Which of the following is an acute phase reactiant that is up-regualted in response to IL-1, IL-6 and TNF-alpha in the liver? A.Albumin B.C-RP and MBL C.IL-8 and IL-12 D.IFN-alpha and beta
B
Which of the following leukocytes is normally classified as a phagocyte? A. B cells B. Neutrophils C. Eosinophils D. Mast cells E. Megakaryocytes
B
Which of the following scenarios represents the most significant challenge in applying a Remicade treatment strategy? A. Reduced coagulation leading to potential bleeding disorder B. Reduced cell-mediated immunity against intracellular pathogens C. Increased susceptibility to cancer D. Reduced humoral mediated immunity E. Reduced neutrophil activity
B
Which one of the following statements best describes innate immunity? A. Has the ability to respond more quickly and robustly on repeated encounter with the same antigen B. Consists in part of anatomical barriers, phagocytes, antimicrobial peptides and complement C. Relies on highly specific receptors that are formed via genetic changes to the loci that code for the receptors termed somatic recombination D. Respond slowly to infection, to allow for clonal proliferation of rare immune cells with specificity for antigen E. Results in the formation of specific antibodies that can neutralize pathogens
B
Which statement best describes the function of dendritic cells? A. Process and present antigen to B cells B. Process and present antigen to T cells C. Secretion of anti-inflammatory cytokines that attenuate inflammation D. Secretion of antimicrobial peptides E. Killing bacteria and fungi
B
A 28-year-old man contracts the tapeworm Diphyllobothrium latum from eating cheap sashimi (raw fish) at a fast-food sushi joint on the corner of Clovis and Shaw. Which immunological mechanism is most critical in the defense against this tapeworm? A. Antimicrobial peptides (AMP) B. Antibody-dependent cellular cytotoxicity (ADCC) C. Direct cytotoxicity via perforin and granzyme D. Intracellular killing using reactive oxygen species E. Extracellular killing via degranulation and NETS
B. Antibody-dependent cellular cytotoxicity (ADCC) - Eosinophils
Which of the following immune cells is primarily responsible for driving the extreme response against the pathogen that has lead to the critically low blood pressure and organ failure (septic shock) in this patient? A. Basophils B. Macrophages C. Neutrophils D. NK cells E. T cells
B. Macrophages - a massive producer of pro-inflammatory cytokines.
A 23-year-old man with a history of mild asthma has been experiencing worsening episodes in the last month. His primary care physician prescribes medication to help control his symptoms. Which inflammatory mediators should you target pharmacologically to counteract the bronchostriction AND chemotaxis of immune cells to his lungs? A. IL-8 B. leukotrienes C. bradykinin D. prostaglandin E. Nitric oxide
B. leukotrienes - treat asthmatic patients.
A 4-month-old male infant is being assessed for putative severe combined immunodeficiency (SCID) based on a history of severe, recurrent bacterial, fungal, and viral infections that have required intensive medical interventions. Flow cytometric analysis of his peripheral blood reveals the following findings CD3(-), CD20(-) and CD56(-). Based on the flow cytometric analysis, how would you describe this SCID (there are different categories of SCID)? A. B cell+, T cell-, NK cell+ B. B cell+, T cell-, NK cell- C. B cell-, T cell-, NK cell- D. B cell-, T cell-, NK cell+ E. B cell-, T cell+, NK cell-
C
A 48-year-old male presents at a primary care clinic with a recent history of anemia and hemolysis, as evidenced by hemoglobineria, especially evident in his morning voiding. His past medical history is unremarkable. He appears otherwise healthy. A blood sample is taken and flow cytometric analysis is performed on his peripheral blood cells. Serum is collected and assessed using the CH50 and AH50 test methods, what are the expected lab test results? A. CH50 will be normal, AH50 will be abnormal B. CH50 will be abnormal, AH50 will be normal C. Both CH50 and AH50 will be normal D. Both CH50 and AH50 will be abnormal
C
A 48-year-old male presents at a primary care clinic with a recent history of anemia and hemolysis, as evidenced by hemoglobineria, especially evident in his morning voiding. His past medical history is unremarkable. He appears otherwise healthy. A blood sample is taken and flow cytometric analysis is performed on his peripheral blood cells. The best explanation for his anemia is? A. Increased lysis of RBC due to inherent membrane defect B. Increased phagocytosis of RBC via CR1 uptake in the spleen C. Increased destruction of RBC by MAC-mediated destruction D. Increased destruction of RBC by auto-antibodies E. Anemia is unrelated to the deficiency
C
A 68-year-old man with a history of arthritis has been taking aspirin, a COX inhibitor, to manage his joint pain for the past 4 years. Which of the following inflammatory mediators is most likely inhibited by aspirin, helping to control his pain? A. Bradykinin B. Leukotriene C. Prostaglandin D. Serotonin E. Thromboxane
C
A 9-year-old girl falls and skins her knees, introducing mixed bacteria into the wound. Both an innate and adaptive immune response is mounted against the infection. At what site will the adaptive component of the immune response against the bacteria most likely be mounted in this patient? A. Red bone marrow B. Skin C. Lymph node D. Mucosal-associated lymphoid tissue E. Thymus
C
A new-borne baby has acquired an infection with Streptococcus agalactiae from his mother following a routine vaginal delivery. Which of the following Complement components can bind to the bacterium so as to mark it for phagocytosis (function as an opsonin)? A. C1r B. C2b C. C3b D. C4b E. C5b
C
Deficiency in which of the following complement components is associated with the most severe clinical phenotype, including life-threatening infections and immune-complex disease ? A. C1 B. C2 C. C3 D. C4 E. C5
C
Deposition of immune complex (I:C) in the blood vessels will cause pathology termed vasculitis (inflammation of the blood vessel wall) including in the skin (leading to rash) and in the glomerulus of the kidney. The underlying immunopathology of the vasculitis involves what precise mechanism? A. It binds to Fc Receptors on macrophages and activates them to destroy endothelial cells B. It binds to Complement receptors (CRs) on macrophages and activates them to destroy endothelial cells C. It activates C3 causing recruitment and activation of neutrophils which produce inflammatory factors that damage endothelial cells D. It forms MAC complex in the walls of the blood vessels
C
Genetic analysis is performed to identify the molecular basis of the SCID phenotype. Which of the following cytokine receptor components will most likely exhibit a loss of function mutation in this patient? A. Gp 130 subunit B. IL-2R β common chain C. IL-2R γ common chain D. IL-15 receptor E. Jak-3
C
In general, deficiency in complement components is associated with a selective immune deficiency invovling what types(s) of pathogens? A. Most pathogens B. Most bacteria C. Encapsulated bacteria D. Enveloped viruses E. Extracellular parasites
C
In the process of inducing the antiviral response, pro-inflammatory cytokines and fever are induced. Which of the following statements best explains this finding? A.The viral PAMPs can bind promiscuously to pattern recognition receptors that induce pro-inflammatory cytokines B.Type I IFN induced by the virus can directly induce fever and secretion of pro-inflammatory cytokines C.NK cells can cross-activate macrophage via Type 2 IFN, causing macrophages to release inflammatory mediators D.NK cell-mediated destruction of virally infected cells releases DAMPs that trigger inflammation
C
In the reparative phase of the inflammatory response, which of the following factors secrete by M2 macrophages directly induces the fibroblasts to secrete extracellular matrix components including collagen? A.IL-4 B.IL-6 C.TGF-beta D.TNF-alpha E.VEGF
C
The pattern recognition receptors (PRRs) that responds directly to the viral RNA will induce which of the following cytokines? A.IL-1 B.IL-6 C.IFN-beta D.IFN-gamma E.TNF-alpha
C
What cytokine exhibits extremely pleotropic effects including: inducing the acute phase response in the liver, inducing fever in the central nervous system, promotes cell-mediated immunity, humoral immunity and formation of neutrophils in the bone marrow? A. IL-10 B. IL-12 C. IL-6 D. IL-8 E. IFN-gamma
C
What is the primary site of hematopoiesis in adults? A. lymph node B. mucosal-associated lymphoid organs C. red bone marrow D. spleen E. thymus
C
Which of the following complement components functions as a chemotactic factor for leukocytes? A. C1q B. C2a C. C3a D. C4b E. C5b
C
Which of the following components negatively regulates the Cr1/Cr2 and Masp1/Masp2 proteases belonging to the C1 complex and Mannose-binding lectin complex respectively? A. CD55 and CD59 B. Factor H and Factor I C. C1 Inhibitor (C1Inh) D. Properdin E. Complement receptor 2 (CR2)
C
Which of the following down-stream signaling molecules will be activated following stimulation of a prototypic immunoglobulin receptor family member such as IL-1? A. Activation of JAK/ STATs B. Activation of RAS/MAPK C. Activation of NF-κB D. Activation of SMADs
C
Which of the following statements best describes inflammation? A.Response of the innate and adaptive immune system to a harmful stimulus B.Response of the adaptive immune system to a harmful stimulus C.Response of the vasculature and innate immune system to a harmful stimulus D.Response of the adaptive immune system to a harmful stimulus E.Response of innate cytokines to a harmful stimulus
C
Which of the following statements best describes the effects of IFN-gamma in this clinical scenario? A.Pro-inflammatory factor that promotes inflammation B.Effective against most bacteria by activating all phagocytes C.Effective against intracellular bacteria by activating macrophages and monocytes D.Pyrogenic (fever inducing) to combate bacterial replication E.Enhancement of APC function
C
You are undertaking a 4th year medical elective in Central America. A 5-year -old male child with a history of recurrent infections is undergoing laboratory assessment for a suspect immune deficiency, including Listeria monocytogenes and Leishmania ssp, and Mycobacteria ssp. Despite this, he recovers easily from colds. He was recently brought to the ED with a fever, hypotension, and dyspnea (shortness of breath) following BCG vaccination for TB prophylaxis (live attenuated Mycobaterium bovis). CX (x-ray of his chest) demonstrate the presence of interstitial infiltrates, consistent with a miliary pattern of spread. Assuming that the patient has a defect in a cytokine axis accounting for this clinical phenotype, which of the following cytokines or respective cytokine receptors most likely explains the aptient's susceptibility to these types of infections? A.IFN-alpha B.IL-10 C.IL-12 D.IL-15 E.IL-6
C
A 47-year-old woman presents at her primary care office with fatigue, swelling of the joints in her hands, and muscle pain. The physician suspects the patient has rheumatoid arthritis, which exhibits systemic inflammatory manifestations in addition to affecting the joints. Which of the following factors should be tested to confirm the suspicion that the patient has a systemic inflammatory condition? A. Bradykinin B. Complement C. C-reactive protein D. Histamine E. Prostaglandin
C. C-reactive protein; Prostaglandin - is local; histamine is acute and allergy related;
A 75-year-old woman arrives at the emergency department with a history of fever for the past two days. On physical examination her temperature is 39°C (feverish) and low blood pressure (92/45 mm Hg) with elevated heart rate (111/minute). Lab results demonstrate an elevated WBC count and WBC differential count of 58 segmented neutrophils, 29 band neutrophils, 8 lymphocytes, and 5 monocytes. A blood culture is positive for the Gram (-) bacterium Escherichia coli. While in the ED, she proceeds to go into septic shock and develops multiple organ failure.Which of the following inflammatory mediators is most likely directly causing the vasodilation and subsequent hypotension in the patient? A. Histamine B. Interleukin-6 C. Nitric oxide D. Serotonin E. Thromboxanes
C. Nitric oxide - Histamine is part of allergic reaction, released by mast cells. NO is released during pathogen and activated by macrophage. NO exhibits antimicrobial activity against bacteria and parasites.
A 5-year-old female child is referred to a pulmonologist with a severe cough which has worsened over 3 days. She has a history of repeated severe respiratory infections. Physical exam reveals several skin lesions that culture positive for Staphylococcus aureus, but the child is otherwise normal. Flow cytometry/ WBC differential shows a significant neutrophilia. She is admitted to the hospital. The following morning it is noted that her cough has worsened and she now has a fever of 38.8°C (101.8°F). A chest radiograph reveals infiltrates in the right lower lobe. A sputum sample is collected and the ensuing culture grows colonies of Streptococcus pneumonaie, Aspergillus fumigatus, and Candida albicans -all extracellular organisms. Which of the following tests is the best to confirm your presumptive diagnosis? A. Chemotaxis assays B. Enumeration of band neutrophils on peripheral blood smear C. Nitroblue tetrazolium test D. Bone marrow aspirate to assess myeloid progenitors E. Bronchial alveolar lavage to assess the immune infiltrate of her lungs
C. Nitroblue tetrazolium test
A 5-year-old male presents at the medical office. He has a longitudinal history of recurrent upper and lower respiratory infections caused by Haemophilus influenza and Streptococcus pneumonia. He has a prominent rash on his face and complains of painful joints. Which of the following C' deficiencies would most likely account for his presentation? Select all that apply. A. C1 B. C2 C. C3 D. C4 E. C5
C1, C2, C4
7 year-old-boy with a peanut allergy accidentally consumes a peanut containing chocolate bar after Halloween trick-or-treating. He begins to experience an acute allergic reaction termed anaphylaxis. Which of the following immune cells is most likely causing his allergic reaction? A. Eosinophils B. Macrophages C. Neutrophils D. Mast cells E. NK cells
D
A 14-year-old female patient with a deficeincy in IL-1RA (DIRA) is receiving treatment for pustular dermatitis and symptoms of osteomyelitis. Which of the following explanations best explains her current condition? A. Defective activation of neutrophils B. Immune deficiency to bacteria and fungi C. Failure to activate CASPASE-1 (ICE) D. Loss of negative regulation of IL-1
D
A 27-year-old seasonal farm worker contracts Human SARS Coronavirus-2 (COVID-19). His NK cells recognize and destroy virus-infected cells in his airways during the early response to the infection. Which of the following factors released by NK cells will kill his infected cells? A. Cationic proteins such as MBP B. Complement component C. Antimicrobial peptides such as alpha-defensins D. Perforin and granzyme E. Reactive oxygen and nitrogen species
D
A 3-year-old girl is scratched by her cat, introducing the bacterium Bartonella henselae into the wound. Which of the following leukocyte types is directly involved in the elimination of the bacterial infection during the innate immune response? A. Basophils B. Dendritic cells C.Eosinophils D. Neutophils E. NK cells
D
A 4-year old female presents at the emergency department with a rash, severe headache, neck stiffness, vomiting and high fever. Her mother explains that her daughter has a history of recurrent, severe pneumonia, meningococcal meningitis and septicemia and joint issues. Lumbar puncture (spinal tap) identifies diplococci Neisseria meningitidis in the cerebral spinal fluid (CSF). Serum is collected and assessed using the CH50 and AH50 test methods, What will the expected test results most likely reveal for this patient? A. CH50 will be normal, AH50 will be abnormal B. CH50 will be abnormal, AH50 will be normal C. Both CH50 and AH50 will be normal D. Both CH50 and AH50 will be abnormal
D
A 4-year old female presents at the emergency department with a rash, severe headache, neck stiffness, vomiting and high fever. Her mother explains that her daughter has a history of recurrent, severe pneumonia, meningococcal meningitis and septicemia and joint issues. Lumbar puncture (spinal tap) identifies diplococci Neisseria meningitidis in the cerebral spinal fluid (CSF). Given her presentation and history, your initial thought is that the patient is deficient in which of the following complement factors? A. C1 B. C2 C. C3 D. C5, C6, C7, C8, C9 E. Factor H and Factor I
D
A 5-year-old male presents at the medical office. He has a longitudinal history of recurrent upper and lower respiratory infections caused by Haemophilus influenza and Streptococcus pneumonia. He has a prominent rash on his face and complains of painful joints. How would you describe immune system function in this patient as a result of this defect and why? A. Extremely impaired because C3 activation cannot occur B. Extremely impaired because C5 activation cannot occur C. Moderately impaired because the lectin pathway and alternative pathway are still intact D. Worse than moderately impaired because only the alternative pathway is still intact
D
Destruction of Gram (+) bacteria present in the tears and saliva is achieved thorugh what factor that hydrolyzes peptidoglycan in the cell wall? A. Complement C3 B. Antimicrobial petpides C. Pentraxins D. Lysozyme E. Lactoferrin
D
Destruction of Gram (+) bacteria present in the tears and saliva is achieved through what factor that hydrolyzes peptidoglycan in the cell wall? A. Complement C3 B. Antimicrobial peptides C. Pentraxins D. Lysozyme E. Lactoferrin
D
Which of the following carbohydrate-modified molecules are enriched in the viscous gel that lines the pulmonary airways? A.GlcNAcylated glycoproteins B.Glycosphingolipids C.N-linked glycoproteins D.O-linked glycoproteins E.O-mannosylated glycoproteins
D
Which of the following complement components participate in all 3 Complement activation pathways? A. C1 B. C2 C. C4 D. C5 E. Factor D
D
Which of the following cytokines plays a critical role in wound repair and collagen production by fibroblasts as well as promoting tolerance in T cells? A. IL-1 B. IL-15 C. IFN-alpha D. TGF-beta E. TNF-alpha
D
Which of the following histological findings would be evident in acute inflammation but not chronic inflammation? A.Angiogenesis B.Fibrosis C.Foamy or giant cell macrophages D.Neutrophils E.Plasma cells
D
Which of the following statements best describes how B cells contribute to the host's immune response against a pathogen? A. Antigen processing and presentation to macrophage B. Secretion of cytokines that help other cells C. Secretion of complement components that can opsonize targets D. Secretion of antibodies that participate in neutralization E. Cytotoxicity against virally infected cells and neoplastic
D
A 23-year-old female patient arrives at the Emergency Department with symptoms consistent with sepsis following a urinary tract infection that was "treated" with cranberry juice. Physical exam reveals evidence of coagulation including petechia and purpura (signs of disseminated intravascular coagulation (DIC)). Overproduction of which of the following cytokines is most likely responsible for inducing DIC in this patient? A. IL-1 alpha B. IL-1 beta C. IL-6 D. IL-8 E. TNF-alpha
E
A 24-year-old male arrives at the Emergency Department with symptoms consistent with sepsis following a penetrating wound to his foot 4 days ago that went untreated. Lab tests and a physical exam are confirmatory of the clinical suspicion and confirm the presence of Gram (-) organism in the blood. Recruitment of leukocytes to the wound bed would have been induced by which of the following cytokines? A.IL-1 B.IL-6 C.IL-8 D.IL-12 E.TNF-alpha
E
A 48-year-old woman with HIV arrives at her primary care physician's office with a 3 week history of cough, night sweats, weight loss and extreme fatigue. Chest x-ray reveals significant pleural effusion and her sputum is positive for acid fast bacilli Mycobacterium tuberculosis (TB), indicating that this intracellular bacterium is no longer controlled and disseminating. A deficiency in which of the following cytokines / cognate receptors would account for disseminated infection caused by TB? A. IL-1 and IL-6 B. IL-10 and TGF-beta C. IL-15 D. IFN alpha and IFN beta E. IFN gamma and IL-12
E
A 72-year-old female patient presents at the Emergency Department with fever (103.2°F), tachycardia, and low blood pressure (82/50 mmHg). Lab test results confirm that the patient is experiencing sepsis follwing infection with E. coli. Which of the following factors is directly responsible for her low blood pressure? A.IFN-beta B.IL-6 C.IL-8 D.Histamine E.Nitric oxide
E
A 74-year-old man is admitted to the ER due to severe pneumonia caused by Haemophilus influenzae. As a result of his infection, he becomes hypercoagulable and forms blood clots in the veins of his arms and legs. Which of the following inflammatory mediators is most likely potentiating the hypercoagulable state in this patient? A. Bradykinin B. Histamine C. Leuktrienes D. Nitric oxide E. Thromboxanes
E
A biochemist is studying the process of protein glycosylation utilizing cells isolated from a breast cancer tumor. Analysis of the cells reveals that they are incapable of incorporating glucose into glycoproteins. Which of the following is most likely not synthesized, thereby preventing glycosyltransferases from incorporating glucose into the oligosaccharide portion of glycoproteins in these cells? A.AMP 1-glucose B.CTP 1-glucose C.Glucose 1,6-bisphosphate D.GTP 1-galactose E.UDP 1-glucose
E
An oligosaccharide unit is transferred from dolichol pyrophosphate to an asparagine moiety of a protein in which of the following structures? A.Endosomes B.Lysosomes C.Mitochondria D.Nuclei E.Rough endoplasmic reticulum
E
The C3 convertase formed during activation of the Lectin complement pathway consists of which of the following subcomponents? A. C3aBbC3b B. C3bBb C. C4aC2aC3b D. C4aC3b E. C4bC2a
E
Which of the following cells will become aggressively cytotoxic in response to type I interferon being produced by her infected epithelium? A.Dendritic cells B.Mast cell C.Macrophage D.Neutrophil E. NK cell
E
Which of the following complement components contributes to the formation of the membrane attack complex (MAC)? A. C2a B. C2b C. C3b D. C5a E. C5b
E
Which of the following features of the carbohydrate portion of glycoproteins determines their uptake into lysosomes? A.multiple galactose residues B.N-acetylneuraminic acid residues C.O-linked oligosaccharides D.terminal fucose residues E.terminal mannose 6-phosphate residues
E
A 5-year-old female child is referred to a pulmonologist with a severe cough which has worsened over 3 days. She has a history of repeated severe respiratory infections. Physical exam reveals several skin lesions that culture positive for Staphylococcus aureus, but the child is otherwise normal. Flow cytometry/ WBC differential shows a significant neutrophilia. She is admitted to the hospital. The following morning it is noted that her cough has worsened and she now has a fever of 38.8°C (101.8°F). A chest radiograph reveals infiltrates in the right lower lobe. A sputum sample is collected and the ensuing culture grows colonies of Streptococcus pneumonaie, Aspergillus fumigatus, and Candida albicans -all extracellular organisms. Which of the following constitutes the most probable explanation for the patient's presentation and past medical history? A. Congenital neutropenia B. Defect in antigen presentation C. Lysososmal trafficking disorder (Chediak-Higashi Syndrome) D. Myeloperoxidase deficiency E. NADPH oxidase deficiency
E. NADPH oxidase deficiency
A 33-year-old man presents at your health clinic with chronic hepatitis C infection. On examination, conjunctival icterus (yellowing of the eyes) and abdominal pain is apparent. Clinical labs reveal elevated liver enzymes. A liver biopsy reveals fibrosis and a mass of neoplastic hepatocytes. Histological staining of the biopsy reveals that the neoplastic cells express very low MHC class I levels. Given this finding, which of the following immune cells will be most effective in the control of the neoplasm? A. CD8+ T cells B. Eosinophils C. Macrophages D. Neutrophils E. NK cells
E. NK cells
A 5-year-old female child is referred to a pulmonologist with a severe cough which has worsened over 3 days. She has a history of repeated severe respiratory infections. Physical exam reveals several skin lesions that culture positive for Staphylococcus aureus, but the child is otherwise normal. Flow cytometry/ WBC differential shows a significant neutrophilia. She is admitted to the hospital. The following morning it is noted that her cough has worsened and she now has a fever of 38.8°C (101.8°F). A chest radiograph reveals infiltrates in the right lower lobe. A sputum sample is collected and the ensuing culture grows colonies of Streptococcus pneumonaie, Aspergillus fumigatus, and Candida albicans -all extracellular organisms. The clearance of these organisms from her lungs would be most effectively accomplished through the action of which of the following substances? A. Complement B. C-reactive protein C. Hypochlorite (ClO-) D. Peroxynitrite (ONOO−) E. Superoxide (O2·)
E. Superoxide (O2·) - important for oxygen-dependent killing - This is a phagocytic disorder.
A 75-year-old woman arrives at the emergency department with a history of fever for the past two days. On physical examination her temperature is 39°C (feverish) and low blood pressure (92/45 mm Hg) with elevated heart rate (111/minute). Lab results demonstrate an elevated WBC count and WBC differential count of 58 segmented neutrophils, 29 band neutrophils, 8 lymphocytes, and 5 monocytes. A blood culture is positive for the Gram (-) bacterium Escherichia coli. While in the ED, she proceeds to go into septic shock and develops multiple organ failure. Which of the following pathogen recognition receptors are likely driving the cytokine storm that is underlying her condition?
E. TLR4 Gram (-) has LPS in cell wall. LPS react with TLR4 (homodimer), leading to pro-inflammatory cytokines leading to production of NO.
