Success! In Clinical Laboratory Science – Immunology Practice Test

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• A young woman with recurrent pyogenic infections and low C3 is most likely to have which of the following?
• Central tolerance is established to prevent autoimmunity and occurs in primary lymphoid organs; which pair correctly identifies the organ for each cell type?
• The isotype of an immunoglobulin antibody is defined by which component?
• Why is the rapid plasma reagin (RPR) test for syphilis read macroscopically rather than microscopically?
• Which statement applies to the Fc fragment of an immunoglobulin molecule?
• What is the fundamental difference between innate and adaptive immunity in terms of specificity and memory?
• In immunodiagnostics, what is the purpose of confirming ELISA results with Western blot?
• A molecule found in human serum sometimes used as a tumor marker is
• Which statement correctly describes the alternative pathway in complement activation?
• Which is an example of passive immunity?
• The type of immunity that follows the injection of an immunogen is termed
• Which statement about hepatitis B surface antigen (HBsAg) is true?
• Given anti-HBc and HBsAg and HBeAg reactive with anti-HBs nonreactive, what is the most likely interpretation?
• Autoimmune destruction of pancreatic beta cells leads to which disease?
• Which feature is not characteristic of precipitation reactions?
• Which class of immunoglobulin binds to basophils and mast cells to mediate immediate hypersensitivity reactions?
• Autologous transplantation is defined as a transplant where tissue is taken from and returned to the same individual. Which word best describes this type of graft?
• Which cell type primarily mediates Type IV hypersensitivity?
• In the classical complement pathway, what is the minimum antibody requirement for activation?
• Flow cytometry relies on detecting membrane molecules by using what type of label on antibodies?
• Which statement about T cell independent responses is accurate?
• What is clonal anergy and how does it relate to peripheral tolerance?
• Which antibody isotype is produced first during a primary immune response?
• Which antibody isotype is most abundant in serum?
• In an antibody titration that uses serial dilutions, how should the final antibody titer be reported?
• During class switch recombination, which statement describes what happens to the heavy chain?
• What is complement-mediated cytotoxicity and in which clinical context is it most relevant?
• What is the term for determining antibody concentration by serial serum dilutions?
• What cytokine milieu promotes macrophage activation versus anti-inflammatory responses?
• If a patient has a reactive HIV screening test but nonreactive anti-HIV-1 and anti-HIV-2 results, which test should be performed on the same sample to detect acute infection?
• What are the primary functions of dendritic cells in initiating adaptive immunity?
• Which type of hypersensitivity is T cell–mediated delayed-type hypersensitivity with no antibodies?
• Where do somatic hypermutation and class switch recombination occur?
• In a dimeric IgA molecule, the structure printed in red and indicated by the red arrow is called the
• Loss of self-tolerance results in
• In T cell dependent B cell activation, what happens in germinal centers?
• Describe the mechanism of hapten-protein conjugates in drug allergy.
• Which finding is most characteristic of autoimmune disease in immunology lab panels?
• Multiple myeloma is best described as:
• Which ELISA format is typically used to quantify a cytokine concentration in serum?
• Anti-transglutaminase 2 antibodies are most specific for which disease?
• Which immunoglobulin class is most commonly described as having ten antigen-binding sites in its most common form?
• Corneal tissue may be transplanted successfully because the cornea occupies which type of site?
• Which cell type can act as an antigen-presenting cell for exogenous antigens?
• Rheumatic fever after group A streptococcal infections involves autoimmune attack on which cardiac structures?
• What is a direct immunofluorescence assay used to detect? Provide an example.
• The major class of immunoglobulin found in adult human serum is
• Which immunoglobulin property describes the requirement for helper T cells in antibody production for certain antigens?
• Monoclonal antibodies are produced by
• Which immunoglobulin isotype is typically produced in T cell independent responses?
• What is graft-versus-host disease and which cells cause it?
• Which term describes a small molecule that elicits an immune response only when bound to a larger carrier?
• Which cell type is primarily responsible for phagocytosis in innate immunity?
• A 65-year-old male with fractures and bone pain has bone marrow showing many plasma cells. Which disease should be suspected?
• Describe Type III hypersensitivity mechanisms and give an example.
• Which cell type is not typically part of the adaptive immune response?
• Which test is most specific and sensitive for the diagnosis of celiac disease?
• Which cell is the principal source of interleukin 2?
• HLA typing in transplantation is used to...
• An 11-year-old with fever and sore throat has EBV IgM positive, CMV IgM negative, heterophile test negative. Which diagnosis is most likely?
• Molecules that require T-helper cells to stimulate antibody formation are called
• Which statement is true about HLA expression?
• Donor-recipient HLA matching aims primarily to reduce which adverse outcome?
• Seroconversion is defined as the point at which a person develops detectable antibodies in serum after infection or vaccination.
• How do immunodeficiency disorders affect serological testing interpretation?
• Which serologic finding supports acute EBV infection in the described patient?
• Patients born with an adenosine deaminase deficiency would likely suffer from
• CD8 is a marker primarily for which lymphocyte subset?
• Which statement correctly describes the classical, lectin, and alternative pathways of complement activation?
• An important part of the nonspecific immune response is (are)
• Secretory IgA at mucosal surfaces is typically present as which form?
• The alternative complement pathway can be activated by which of the following?
• Define hypersensitivity Type I and name a classic example and mediator.
• From which precursor do both B lymphocytes and T lymphocytes develop?
• For an antibody-coated antigen to be phagocytized, which antibody region binds to receptors on phagocytes?
• Corticosteroids exert immunosuppressive effects by which mechanism?
• Which statement correctly pairs autoimmune serology tests with what they detect?
• Which cell surface markers define helper T cells (CD4+) and cytotoxic T cells (CD8+) in flow cytometry?
• NK cells target altered host cells, such as tumor cells, based on which signal?
• In the enzyme-linked immunosorbent assay (ELISA), the visible reaction is due to a reaction between
• Which diagnostic approach uses indirect immunofluorescence to reveal staining patterns in autoimmune diseases?
• Human leukocyte antigens (HLAs) are found on
• Antibodies that bind to the same epitope are of the same
• A kidney transplant from one identical twin to another is an example of what type of graft?
• Autoimmune destruction of pancreatic cells leads to which disease?
• Which statement accurately reflects how the classical complement pathway is initiated?
• Which immune cells are primarily responsible for antigen presentation to naive T cells?
• What is the basic principle underlying ELISA assays?
• After adding sensitized sheep red blood cells in the complement fixation test, all tubes show hemolysis. What does this indicate?
• Autoantibodies commonly detected in systemic lupus erythematosus are directed against what type of antigen?
• A small molecule that is not antigenic by itself but becomes antigenic when attached to a carrier is called a
• Which test remains positive for life after syphilis infection and is used to confirm exposure to Treponema?
• Two unrelated individuals receive the seasonal influenza vaccine. You would expect their antibodies to the vaccine immunogens to be of the same which?
• What is flow cytometry used for in an immunology laboratory?
• Which region of an immunoglobulin is primarily responsible for antigen binding?
• A soluble antigen and soluble antibody reacting to form an insoluble product describes which reaction?
• In patients with human immunodeficiency virus (HIV) infection, immune status can be monitored by measuring the ratio of
• Passive immunization provides immediate protection because pre-formed antibodies are administered. Which of the following statements best reflects this?
• An example of immune injury due to deposition of antigen-antibody complexes is which condition?
• What is the difference between active and passive immunity, with examples relevant to clinical practice?
• In rheumatoid arthritis, the serologically detectable antibody is primarily of the class:
• Rheumatic fever following group A streptococcal infections is an example of which autoimmune mechanism?
• What is the purpose of a neutralization assay in clinical laboratory testing?
• The interaction between B cells and T-helper cells involves which of the following?
• Which assay uses a labeled antibody to detect an antigen within a tissue sample?
• Which cytokines are known to activate macrophages in chronic inflammatory diseases?
• What characterizes memory in adaptive immunity?
• X-linked agammaglobulinemia is a primary immunodeficiency characterized by which feature?
• Hyposensitization protocols for pollen allergy involve injections of which substance?
• What is the role of complement protein C3b in immune defense?
• A male infant with recurrent infections and virtual lack of gamma globulins, but normal T cell numbers and function, most likely has which condition?
• Which process enables B cells to produce different antibody isotypes (e.g., IgG, IgA, IgE) after initial IgM production?
• Severe combined immunodeficiency (SCID) is an
• A sandwich ELISA is used to detect antigen by capturing it between two antibodies to quantify it.
• In X-linked agammaglobulinemia, which immune cells are deficient?
• Natural killer cells are part of which arm of the immune system?
• Anti-CCP antibodies play what role in autoimmune arthritis diagnosis?
• The first immune cell type to respond when a finger wound is contaminated with Staphylococcus aureus is?
• Which complement protein is part of the membrane attack complex?
• What is the primary cellular target of human immunodeficiency virus?
• Which statement correctly distinguishes T cell dependent B cell activation from T cell independent activation?
• Rheumatoid factor testing detects autoantibodies directed against which portion of immunoglobulin G?
• What is the primary purpose of serology testing in infectious disease?
• In the complement system, C3b functions primarily as which?
• Which fragment of an antibody contains the Fc region?
• Elevated IgE levels are typically found in
• Original antigenic sin refers to which immunological phenomenon?
• Which cell type is primarily responsible for antibody production?
• The patient with symptoms including tachycardia and thyroid enlargement has T3 and T4 elevated with a suppressed TSH. Which antibody is most likely present?
• Which molecule acts as an opsonin to enhance phagocytosis in the complement system?
• Which serologic pattern is most diagnostic of an acute infection?
• In multiple myeloma, malignant cells are derived from which lineage?
• What is the functional consequence of immunoglobulin heavy chain class switch recombination?
• How does the secondary humoral immune response differ from the primary response?
• HIV infection is a common acquired immunodeficiency. Which combination of tests is commonly used for diagnosis and staging?
• Alloantibodies are antibodies directed against non-self alloantigens from the same species. They are most relevant in which clinical contexts?
• Complement-mediated cytotoxicity is most relevant in which clinical scenario?
• Which antibody type is predominant in the serum of neonates born after full-term gestation?
• The first serologic marker to appear in acute hepatitis B virus infection is which of the following?
• Cells that can act as antigen-presenting cells for exogenous antigens include which of the following?
• Which virus is dependent on co-infection with hepatitis B virus for replication?
• Which statement best defines a hapten in immunology?
• Which of the following is a characteristic of T cells?
• Name the four major antibody isotypes and one key function of each.
• Which statement describes a direct immunofluorescent assay?
• Which of the following is an example of a treponemal antigen test used for the diagnosis of syphilis?
• Which heavy chain is unique to the IgD immunoglobulin class?
• After exposure to antigen, the first antibodies detectable belong to which class?
• Differentiate between T helper 1 (Th1) and T helper 2 (Th2) responses in terms of cytokines and pathogen defense.
• In a competitive ELISA, which statement describes the correct competition mechanism?
• The Fab portion of an antibody contains the hypervariable region.
• The Venereal Disease Research Laboratory (VDRL) test for syphilis is classified as which type of reaction?
• What term describes antibodies produced from a single clone of B cells?
• Which virus is most likely responsible for the acute infectious illness described in the 11-year-old given EBV IgM positivity?
• Define an epitope and explain why it is important for antigen recognition.
• Which antibody class is most often implicated in hyperacute graft rejection due to preformed donor antibodies?
• Which condition is a classical example of Type IV hypersensitivity?
• In term newborns, detection of which antibody indicates the infant's own immune production rather than maternal transfer?
• Skin testing is a useful diagnostic tool in disorders such as tuberculosis. Which statement is true?
• Which is an example of passive immunity used in clinical practice?
• Which statement about B lymphocytes is correct?
• Which statement characterizes contact dermatitis?
• In bone marrow transplantation, immuno-competent donor cells may respond to recipient antigens, leading to which complication?
• A hapten is best described as which?
• Which cytokine is primarily produced by T cells and drives T cell proliferation?
• A patient report states the presence of serum antibodies to OspC. This finding most likely indicates which disease?
• Incompatible blood transfusions are examples of which type of hypersensitivity?
• A human cell with CD8 on its surface is most likely a
• During a primary immune response, which antibody is produced first?
• Type I hypersensitivity is
• Which immunoglobulin is efficiently transported across the placenta from mother to fetus?
• ADA deficiency is associated with which primary immunodeficiency?
• Which organ do T cells mature in?
• Which organ is the primary site for B cell maturation?
• Bruton agammaglobulinemia results in the absence of immunoglobulins due to a defect in which process?
• What is the stated advantage of using immunofluorescence testing to diagnose systemic lupus erythematosus?
• A serum sample is positive for HBsAg. This result indicates that the person from whom the serum was taken
• Which statement about natural killer (NK) cells is true?
• Which immunoglobulin class is most commonly associated with allergic reactions?
• The region of an antibody that contains the antigen-binding sites is the
• Antibodies produced by a single clone of plasma cells are called which of the following?
• Hashimoto disease is an autoimmune disorder primarily involving which gland?
• Skin testing relies on which type of hypersensitivity mechanism?
• A major advantage of passive immunization compared to active immunization is that
• The strength with which a multivalent antibody binds a multivalent antigen is termed the
• Which of the following statements about immunoglobulin light chains is true?
• What is the primary mechanism responsible for pathology in systemic lupus erythematosus?
• Why does vaccination against hepatitis B virus (HBV) also prevent hepatitis D virus (HDV) infections?
• Which statement correctly describes the relationship between HBV and HDV infections?
• In the described hepatitis B serology, which marker indicates current HBV infection?
• Graft-versus-host disease most commonly arises after which type of transplantation?
• In the hepatitis B serology case, which marker indicates a lack of protective immunity against HBV?
• Which class of immunoglobulin possesses delta heavy chains?
• In systemic lupus erythematosus, the autoantibody most frequently present is directed against which antigen?
• Identical antibodies produced from a single clone of plasma cells are described as which type of antibodies?
• Cell-mediated immunity is primarily mediated by which cell type?
• Elevated antithyroglobulin and antithyroid peroxidase are suggestive of
• In the complement system, which statement is correct?
• Bruton disease is characterized by the absence of which immunoglobulins?
• A soluble mediator produced by lymphocytes is known as a
• Graft-versus-host disease most commonly occurs after which type of transplant?
• Original antigenic sin has implications for immune responses to related antigens; which statement best captures its impact?
• You would expect patients suffering from selective IgA deficiency to present with
• What process increases the affinity of antibodies during an immune response?
• Innate immunity includes which of the following processes?
• During an antibody titration, which pattern indicates a prozone reaction?
• In a chemiluminescent immunologic assay, what is the signal detected?
• What test patterns are seen on ANA immunofluorescence and what is their clinical significance?
• What is the role of MHC class I and class II molecules in antigen presentation?
• Which non-treponemal syphilis test uses charcoal-labeled particles to allow macroscopic reading?
• Mucosal immunity is primarily mediated by which immunoglobulin class, typically present as a dimeric secretory form?
• One condition that can cause a false-positive VDRL test is which of the following?
• A living donor is sought for a child needing a kidney transplant. The best odds of finding an MHC-compatible donor occur between the child and
• "Superantigens" cause damage by which mechanism?
• Diagnosis of group A streptococci infection is indicated by the presence of which antibody?
• Which tumor marker is most commonly used to screen for hepatocellular carcinoma?
• Identification of cells based on membrane molecules by flow cytometry involves which labeling method?
• Which class of immunoglobulin possesses 10 antigenic binding sites?
• Describe Type II hypersensitivity mechanisms and give an example.
• Lymphokines are soluble mediators produced by which cells?
• Regulatory T cells (Tregs) play a key role in maintaining immune tolerance. Which phenotype best describes them?
• Which statement about the C-reactive protein (CRP) test is true?