Skin pH that keeps most microorganisms from growing: A. 5.6 B. 6.5 C. 7.2 D. 8.0

Primary function of the eosinophil: A. Phagocytosis B. Suppression of the inflammatory response C. Reacting in acute, systemic hypersensitivity reactions D. Antigen recognition

Interferons (IFN) have been demonstrated to act as: A. Immunomodulators B. Antiviral agents C. Antineoplastic agents D. All of these

The process of inflammation is characterized by all of the following except: A. Increased blood supply to the area B. Migration of white blood cells C. Decreased capillary permeability D. Appearance of acute-phase reactants

Acute-phase reactants are produced primarily by: A. Endothelial cells B. Epithelial cells C. Fibroblasts D. Hepatocytes (liver parenchymal cells)

The acute phase reactant that has the fastest response time and can rise 100x is: A. Alpha-1 antitrypsin B. Haptoglobin C. C-reactive protein D. Ceruloplasmin

Measurement of CRP levels can be used for all of the following except: A. Monitoring drug therapy with anti-inflammatory agents B. Tracking the normal progress of surgery C. Diagnosis of a specific bacterial infection D. Determining active phases of rheumatoid arthritis

. In plasma, this acute phase reactant is associated with HDL cholesterol, and it is thought to play a role in metabolism of cholesterol: A. CRP B. Ceruloplasmin C. Haptoglobin D. Serum amyloid

Hypochlorite and hydroxyl ions damage _______ irreversibly, occur in the oxygen-dependent phase of phagocytosis. A. DNA B. Carbohydrate C. Lipid D. Protein

Neutrophil phagocytosis and particle ingestion are associated with an increase in oxygen utilization called respiratory burst. What are the two most important products of this biochemical reaction? A. Hydrogen peroxide and superoxide anion B. Lactoferrin and NADPH oxidase C. Cytochrome b and collagenase D. Alkaline phosphatase and ascorbic acid

Which is the most significant agent formed in the phagolysosome for the killing of microorganisms? A. Proteolytic enzymes B. Hydroxyl radicals C. Hydrogen peroxide D. Superoxides

Which is the most significant agent formed in the phagolysosome for the elimination of microorganisms? A. Proteolytic enzymes B. Hydrogen ions C. Hypochlorite ions D. Superoxides

A DPT vaccination is an example of: A. Active humoral-mediated immunity B. Passive humeral-mediated immunity C. Cell-mediated immunity D. Immediate hypersensitivity

Which of the following cell surface molecules is classified as an MHC class II antigen? A. HLA-A B. HLA-B C. HLA-C D. HLA-DR

Antigen receptors on T lymphocytes bind HLA class II molecules with the help of which accessory molecule? A. CD2 B. CD3 C. CD4 D. CD8

What molecule on the surface of most T cells recognizes antigen? A. IgT B. MHC protein C. CD3 D. TcR

The main function of T cells in the immune response is to: A. Produce cytokines that regulate both innate and adaptive immunity B. Produce antibodies C. Participate actively in phagocytosis D. Respond to target cells without prior exposure

Which cluster of differentiation (CD) marker appears during the first stage of T-cell development and remains present as an identifying marker for T cells? A. CD1 B. CD2 C. CCD3 D. CD4 or CD8

Which cluster of differentiation is MOST SPECIFIC identifying marker for mature T cells? A. CD1 B. CD2 C. CD3 D. CD4 or CD8

Less expensive to perform and is of historic significance, because this represents the first means of T-cell identification: A. Monoclonal antibodies B. Flow cytometry C. Rosette test D. None of these

This T cell defect is a congenital anomaly that represents faulty embryogenesis, which results in aplasia of the parathyroid and thymus glands: A. DiGeorge syndrome B. Ataxia telangiectasia C. Bruton agammaglobulinemia D. Wiskott-Aldrich syndrome

In testing for DiGeorge’s syndrome, what type of laboratory analysis would be most helpful in determining the number of mature T cells? A. Complete blood count B. Nitroblue tetrazolium (NBT) test C. T-cell enzyme assays D. Flow cytometry

A transplant patient began to show signs of rejection 8 days after receipt of the transplanted organ, and the organ was removed. What immune elements might be found in the rejected organ? A. Antibody and complement B. Primarily antibody C. Macrophages D. T cells

Patients at risk for graft-versus-host disease (GVHD) include each of the following, EXCEPT recipients of: A. Bone marrow transplants B. Lung transplants C. Liver transplants D. Irradiated leukocytes

Marginal B cells remain in the: A. Bone marrow B. Lymph nodes C. Spleen D. Thymus

Which of the following is the most common humoral immune deficiency disease? A. Bruton agammaglobulinemia B. Selective IgA deficiency C. IgG deficiency D. Wiskott-Aldrich syndrome

An 18-month-old boy has recurrent sinopulmonary infections and septicemia. Bruton’s X-linked immunodeficiency syndrome is suspected. Which test result would be markedly decreased? A. Serum IgG, IgA, and IgM B. Total T-cell count C. Both B- and T-cell counts D. Lymphocyte proliferation with phytohemagglutinin stimulation

Macrophages produce which of the following proteins during antigen processing? A. IL-1 and IL-6 B. γ-Interferon C. IL-4, IL-5, and IL-10 D. Complement components C1 and C3

Which of the following best describes a HAPTEN? A. Not able to react with antibody B. Antigenic only when coupled to a carrier C. Has multiple determinant sites D. A large chemically complex molecule

Haptenic determinant will react with: A. Both T cells and antibody B. T cells but not antibody C. Neither T cells nor antibody D. Antibody but not T cells

A synonym for an ANTIGENIC DETERMINANT is: A. Immunogen B. Epitope C. Binding site D. Polysaccharide

UNIQUE AMINO ACID SEQUENCE THAT IS COMMON TO ALL IMMUNOGLOBULIN MOLECULES of a given class in a given species: A. Isotype B. Allotype C. Idiotype D. Any of these

Antibody class/isotype and antibody subclass are determined by major physiochemical differences and antigenic variation found primarily in the: A. Constant region of heavy chain B. Constant region of light chain C. Variable regions of heavy and light chains D. Constant regions of heavy and light chains

Antibody allotype is determined by the: A. Constant region of heavy chain B. Constant region of light chain C. Variable regions of heavy and light chains D. Constant regions of heavy and light chains

Antibody idiotype is dictated by the: A. Constant region of heavy chain B. Constant region of light chain C. Variable regions of heavy and light chains D. Constant regions of heavy and light chains

The ratio of kappa to lambda light chain-producing cells in normal individuals is: A. 1:1 B. 2:1 C. 3:1 D. 4:1

All of the following are functions of immunoglobulins except: A. Neutralizing toxic substances B. Facilitating phagocytosis through opsonization C. Interacting with TC cells to lyse viruses D. Combining with complement to destroy cellular antigens

Treatment of IgG with papain results in how many fragments from each immunoglobulin molecule? A. 2 B. 3 C. 4 D. 5

Which of the following immunoglobulins is present in the highest concentration in normal human serum? A. IgM B. IgG C. IgA D. IgE

The key structural difference that distinguishes immunoglobulin subclasses is the: A. Number of domains B. Stereometry of the hypervariable region C. The sequence of the constant regions D. Covalent linkage of the light chains

The SUBCLASSES of IgG differ mainly in: A. Type of L chain B. Arrangement of disulfide bonds C. Ability to act as opsonins D. Molecular weight

Which lgG subclass is most efficient at crossing the placenta? A. lgG1 B. lgG2 C. lgG3 D. lgG4

Which antibody is best at agglutination and complement fixation? A. IgA B. IgG C. IgD D. IgM

Which of the following statements about IgM is false? A. Composed of five basic subunits B. More efficient in the activation of the complement cascade and agglutination than IgG C. Predominant in an initial antibody response D. Predominant in a secondary (anamnestic) response

Which best describes the role of the SC of IgA? A. A transport mechanism across endothelial cells B. A means of joining two IgA monomers together C. An aid to trapping antigen D. Enhancement of complement fixation by the classical pathway

Which represents the main function of IgD? A. Protection of the mucous membranes B. Removal of antigens by complement fixation C. Enhancing proliferation of B cells D. Destruction of parasitic worms

All of the following are immunologic functions of complement except: A. Induction of an antiviral state B. Opsonization C. Chemotaxis D. Anaphylatoxin formation

Which region determines whether an immunoglobulin molecule can fix complement? A. VH B. CH C. VL D. CL

Which of the following statements is false about an anamnestic response versus a primary response? A. Has a shorter lag phase B. Has a longer plateau C. Antibodies decline more gradually D. IgM antibodies predominate

In a secondary (anamnestic) response, all the following characteristics are correct except: A. IgG is the predominant antibody type B. It has a shorter lag phase C. The antibody titer is lower D. It has a more gradual decline in antibody response

Most plasma complement proteins are synthesized in the LIVER with the exception of: A. C1 and Factor B B. C1 and Factor D C. C3 and Factor B D. C3 and Factor D

. Which complement component is present in the greatest quantity in plasma? A. 2 B. 3 C. 4 D. 8

The three complement activation pathways converge at the point of cleavage of complement component: A. C3 B. C5 C. C7 D. C8

Which of the following releases histamine and other mediators from basophils? A. C3a B. Properdin factor B C. C1q D. C4

Which of the following complement components is a strong CHEMOTACTIC FACTOR as well as a strong ANAPHYLATOXIN? A. C3a B. C3b C. C5a D. C4a

Which of the following activities is associated with C3b? A. Opsonization B. Anaphylaxis C. Vasoconstriction D. Chemotaxis

Mannose-binding protein in the lectin pathway is most similar to which classical pathway component? A. C3 B. C1rs C. C1q D. C4

Complement can be inactivated in human serum by heating to _____° C. A. 25 B. 37 C. 45 D. 56

A specimen should be reinactivated when more than ______ hour(s) has (have) elapsed since inactivation. A. 1 B. 2 C. 4 D. 8

Which outcome indicates a negative result in a complement fixation test? A. Hemagglutination B. Absence of hemagglutination C. Hemolysis D. Absence of hemolysis

What is a general definition for autoimmunity? A. Increase of tolerance to self-antigens B. Loss of tolerance to self-antigens C. Increase in clonal deletion of mutant cells D. Manifestation of immunosuppression

Laboratory features of SLE include: A. The presence of ANAs B. Circulating anticoagulant and immune complexes C. Decreased levels of complement D. All of the above

What disease is indicated by a high titer of anti-Sm (anti-Smith) antibody? A. Mixed connective tissue disease (MCTD) B. RA C. SLE D. Scleroderma

Which immunofluorescence pattern indicates the need for ENA testing by Ouchterlony immunodiffusion, Multiplex, or ELISA assays? A. Homogeneous or solid B. Peripheral or rim C. Speckled D. Nucleolar

Rheumatoid factor is most often of which of the following classes: A. IgE B. IgA C. IgM D. IgG

Rheumatoid factor consists of antibodies that bind the: A. Fc portion of IgG molecule B. Fab portion of IgG molecule C. Fc portion of IgM molecule D. Fab portion of IgM molecul

A patient with joint swelling and pain tested negative for serum RF by both latex agglutination and ELISA methods. What other test would help establish a diagnosis of RA in this patient? A. Anti-CCP B. ANA testing C. Flow cytometry D. Complement levels

A laboratory is evaluating an enzyme-linked immunosorbent assay (ELISA) for detecting an antibody to cyclic citrullinated peptide (CCP), which is a marker for rheumatoid arthritis. § The laboratory includes serum from healthy volunteers and patients with other connective tissue diseases in the evaluation. These specimens determine which factor of the assay? A. Sensitivity B. Precision C. Bias D. Specificity

In PRIMARY BILIARY CIRRHOSIS, which of the following antibodies is seen in high titers? A. Antimitochondrial B. Anti-smooth muscle C. Anti-DNA D. Anti-parietal cell

Which disease might be indicated by antibodies to smooth muscle? A. Atrophic gastritis B. Autoimmune hepatitis C. Myasthenia gravis D. Sjögren’s syndrome

Antibodies to thyroid peroxidase can be detected by using agglutination assays. Which of the following diseases may show positive results with this type of assay? A. Graves’ disease and Hashimoto’s thyroiditis B. Myasthenia gravis C. Granulomatous thyroid disease D. Addison’s disease

n Grave’s disease, one of the main autoantibodies is: A. Anti-CCP B. Antibody to islet cells of pancreas C. Antibody to thyroid-stimulating hormone receptor D. Anti-dsDNA

HLA-B8 ANTIGEN has been associated with which of the following pairs of diseases? A. Ankylosing spondylitis and myasthenia gravis B. Myasthenia gravis and celiac disease C. Celiac disease and akylosing spondylitis D. Reiter disease and multiple sclerosis

Which immunologic mechanism is usually involved in BRONCHIAL ASTHMA? A. Immediate hypersensitivity B. Immune complex C. Antibody mediated cytotoxicity D. Delayed hypersensitivity

After a PENICILLIN injection, a patient rapidly develops respiratory distress, vomiting and hives. This reaction is primarily mediated by: A. IgG B. IgA C. IgM D. IgE

In skin tests, WHEAL AND FLARE development is indicative: A. Immediate hypersensitivity B. Anergy C. Delayed hypersensitivity D. Arthus reaction

Which test would measure the coating of red cells by antibody as occurs in hemolytic transfusion reactions? A. Indirect antiglobulin test (IAT) B. Direct antiglobulin test (DAT) C. ELISA D. Hemagglutination

Which of the following conditions will most likely result in a false-negative DAT test? A. Insufficient washing of RBCs B. Use of heavy chain–specific polyclonal anti-human Ig C. Use of excessive centrifugal force D. Use of a sample obtained by finger puncture

Type III reactions are exemplified by all the following except: A. Arthus reaction B. Serum sickness C. Glomerulonephritis D. Shingles

Which test is used to evaluate the cellular immune system in a patient? A. Skin test for commonly encountered antigens B. Determination of isohemagglutinin titer C. Immunoelectrophoresis of serum D. Lymphocyte proliferation to mitogen/antigen

What immune elements are involved in a positive skin test for tuberculosis? A. IgE antibodies B. T cells and macrophages C. NK cells and IgG antibody D. B cells and IgM antibody

How can interfering cold agglutinins be removed from a test sample? A. Centrifuge the serum and remove the top layer B. Incubate the clot at 1 to 4°C for several hours, then remove serum C. Incubate the serum at 56°C in a water bath for 30 minutes D. Use an anticoagulated sample

All positive cold agglutinin tubes remain positive after 37°C incubation except the positive control. What is the most likely explanation for this situation? A. High titer cold agglutinins B. Contamination of the test system C. Antibody other than cold agglutinins D. Faulty water bath

What is the “M” component in monoclonal gammopathies? A. IgM produced in excess B. μ Heavy chain produced in excess C. Malignant proliferation of B cells D. Monoclonal antibody or cell line

The most common application of IEP of serum is for the: A. Diagnosis of monoclonal gammopathy B. Diagnosis of polyclonal gammopathy C. Diagnosis of autoimmune hemolysis D. Demonstration of Bence Jones (BJ) protein

The most important application of IEP of urine is: a. A. Diagnosis of monoclonal gammopathy B. Diagnosis of polyclonal gammopathy C. Diagnosis of autoimmune hemolysis D. Demonstration of Bence Jones (BJ) protein

Patients with Waldenström’s macroglobulinemia exhibit abnormally large amounts of: A. IgM B. IgG C. IgE D. IgA

The interaction between an individual antigen and antibody molecule depends upon several types of bonds such as ionic bonds, hydrogen bonds, hydrophobic bonds, and van der Waals forces. How is the strength of this attraction characterized? A. Avidity B. Affinity C. Reactivity D. Valency

Which of the following type(s) of bonding is (are) involved in antigen-antibody reactions? A. Hydrophobic B. Hydrogen C. Van der Waals D. All of the above

Bonding of antigen to antibody exists exclusively as: A. Hydrogen bonding B. Van der Waals forces C. Electrostatic forces D. Noncovalent bonding

Which of the following describes an antigen antibody reaction? A. The reaction is reversible B. The reaction is the same as a chemical reaction C. A lattice is formed at prozone D. A lattice is formed at postzone

When soluble antigens diffuse in a gel that contains antibody, in which zone does optimum precipitation occur? A. Prozone B. Zone of equivalence C. Postzone D. Prezone

A soluble antigen and soluble antibody reacting to form an insoluble product describes A. Agglutination reactions B. Heterophile reactions C. Labeled reactions D. Precipitation reactions

Which of the following is the most common application of IMMUNOELECTROPHORESIS (IEP)? A. Identification of the absence of a normal serum protein B. Structural abnormalities of proteins C. Screening for circulating immune complexes D. Diagnosis of monoclonal gammopathies

In FPIA, labeled antigens compete with unlabeled antigen in the patient sample for a limited number of antibody binding sites. The MORE antigen that is present in the patient sample: A. Less fluorescence B. Greater fluorescence C. Less fluorescence polarization D. Greater fluorescence polarization

MAJOR SYSTEMS IN A FLOW CYTOMETER include all of the following except: TURGEON A. Fluidics B. Optics C. Computerized electronics D. Gating

Flow cytometry characterizes cells on the basis of which of the following? A. Forward and 90-degree side scatter of an interrupted beam of light B. Front-angle scatter only of an interrupted light beam C. Absorbance of light by different types of cells D. Transmittance of light by cells in solution

What effect does selecting the wrong gate have on the results when cells are counted by flow cytometry? A. No effect B. Failure to count the desired cell population C. Falsely elevated results D. Impossible to determine

What is the immunologic method utilized in the FLOW CYTOMETER? A. Latex agglutination B. Immunofluorescence C. Enzyme linked immunoassay D. Radioimmunoassay

What temperature is used to achieve DNA denaturation to a single strand? A. 74 °C B. 92 °C C. 94 °C D. 102 °C