IUHS Immunology Exam Master Questions

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A skin transplantation experiment was performed in a laboratory. During the experiment, skin grafts were transplanted between MHC-identical mice. The skin grafts will be rejected by? Female recipients with grafts from female donors Male recipients with grafts from female donors Male recipients with grafts from male donors Female recipients with grafts from male donors All male and female animals

Female recipients with grafts from male donors

Many antigens and all immunoglobulins are proteins. The identification of these proteins depends on various techniques that separate and characterize them. One method commonly used in the research laboratory is polyacrylamide electrophoresis of proteins treated with sodium dodecyl sulfate, or SDS-PAGE, which separates proteins based on what factor? Charge Affinity Size Isoelectric point Epitope

Size

What is the ability of an antibody to distinguish its immunogen from other antigens called? Amount Isotype Specificity Affinity Heavy chain

Specificity

After an infection, activated T cells are no longer needed, and cessation of the antigenic stimulus prompts them to undergo programmed cell death or apoptosis. One mechanism of apoptosis that has been well defined is the interaction of the receptor molecule Fas on T cells with its ligand FasL. The signaling activity leading to apoptosis begins with what receptor interacting molecule? ICAM-1 FADD Mac-1 LFA-1 VLA-4

FADD

Which of the following best defines a hapten? Any protein or carbohydrate that enters the body Any substance that is able to combine with T or B cells A substance that binds to a specific site on the Fab fragments of antibodies A simple substance that is not immunogenic itself but can react with a specific antibody Any substance that can evoke an immune response

A simple substance that is not immunogenic itself but can react with a specific antibody

Virtually any substance can elicit an antibody response. The response to even a single antigen is diverse, comprising many different antibody molecules each with a unique affinity and fine specificity. Examination of the antibody molecules generated in an immune response using various techniques leads to an understanding of this diversity. Equilibrium dialysis can be used to measure a characteristic of a specific antibody. Data are then analyzed. What is the characteristic measured? Avidity Affinity Size Concentration Stability

Affinity

A single B lymphocyte produces an immunoglobulin of only one specificity. A given B cell has two sets of chromosomes, one set from each parent, so theoretically, immunoglobulin genes located on both chromosomes could synthesize immunoglobulin molecules. This does not occur. Immunoglobulin chains are coded for by only one set of genes, either from the maternal or the paternal chromosome. For example, the heavy chain may be coded for by genes on the paternal chromosome and the light chain by genes on the maternal chromosome. What is this phenomenon called? Molecular mimicry Gene conversion Allelic exclusion Transgenesis Antigenic shift

Allelic exclusion

As a result of gene rearrangement, what does each B cell produce? A diverse spectrum of antibodies of various specificities An antibody of a single specificity No antibodies A restricted set of different antibodies Both kappa and lambda light chains and a single heavy chain

An antibody of a single specificity

Tissue grafts placed in some sites in the body do not elicit immune responses. The grafts do not induce graft rejection via "host-versus-graft" or "graft-versus-host" mechanisms. Such locations are termed "immunologically privileged sites," and they include what regions? Brain, testis, stomach Testis, eye, thyroid Brain, eye, bone marrow Brain, eye, testis Brain, testis, muscle

Brain, eye, testis

SDF-1 is a small chemokine of the CXC subfamily that is produced constitutively by bone marrow stromal cells and has an important role in early stages of B cell development. It is a growth factor for B cell progenitors and a chemotactic factor for T cells, monocytes, CD34+ hematopoietic progenitor cells, mature megakaryocytes, and dendritic cells. What is the chemotactic effect of SDF-1 mediated by? Mac-1 SDF-1 CXCR-4 IL-8 IP-10

CXCR-4

Chemokines are an important group of proteins that play a major role in the mobilization and activation of blood leukocytes. They are produced in various disease states involving acute and chronic inflammatory processes, including arthritis, angiogenesis, arteriosclerosis and respiratory processes such as asthma. The CC subfamily of chemokines include MCP-1, RANTES, and what else? IL-8 Mac-1 Eotaxin SDF-1 Lymphotactin

Eotaxin

Self tolerance in T lymphocytes is initially induced mainly within the thymus in fetal and perinatal life by a process of clonal selection (negative selection) and deletion of self-reactive immature T cells, presumably initiated by reaction of their receptors with self antigen complexed with self MHC molecules. Most of thymic T cells die within the thymus, reflecting negative selection by a natural process of programmed cell death called apoptosis. What mediates apoptosis of self-reactive T cells in the perinatal thymus? Fas CEA AFP MAGE Ras

Fas

One of the most important features that mast cells and basophils have in common is that they both have immunoglobulin receptors on their membranes called what? G-CSF IκB IL-2 EPO FcεRI

FcεRI

Understanding how cytokines affect their target cells has been the subject of many recent studies. Clinically, knowledge about cytokine-cytokine receptor interactions may be useful in devising strategies to prevent the action of cytokines involved in inflammatory responses, such as rheumatoid arthritis, or in responses such as transplantation rejection. Most cytokines identified to date bind to the class I family of cytokine receptors. What is one example of these? Fas G-CSF IL-8 RANTES MAGE

G-CSF

Continued presence of which of the following hepatitis B virus (HBV) antigens in serum may indicate the carrier state? HBsAg HBeAg HBcAg DNA polymerase HBV DNA

HBsAg

The major histocompatibility complex (MHC) of genes consists of a linked set of genetic loci encoding many of the proteins involved in antigen presentation to T cells, most notably the MHC glycoproteins that present peptides to the T cell receptor. The major histocompatibility complex contains more than 200 genes in humans. Genes encoding the α chains of MHC class I molecules and the α and β chains of MHC class II molecules are linked within the complex. The particular combination of MHC alleles found on an individual chromosome is known as an MHC? Isotype Allotype Haplotype Idiotype Agretope

Haplotype

Selectins are a family of transmembrane molecules with a common core structure, distinguished from each other by the presence of different lectin-like domains in their extracellular portion. The selectins are particularly important for leukocyte homing to specific tissues, and can be expressed on the surface of leukocytes or on vascular endothelium. The smallest of the vascular selectins is the leukocyte-specific selectin. What is it called? Mac-1 LFA-1 L-selectin VLA-4 ICAM-1

L-selectin

What is one adaptive mechanism used in malaria? Latency Persistence Virulence Opportunism Tolerance

Latency

Tissue macrophages have on their surfaces receptors able to recognize components common to many pathogens. These receptors include the macrophage mannose receptor, which is found on macrophages but not on monocytes or neutrophils. The macrophage mannose receptor is a member of what calcium-dependent family? Immunotoxins Streptolysins Immunophilins Endotoxins Lectins

Lectins

The eosinophil is a terminally differentiated, end-stage leukocyte that resides predominantly in submucosal tissue and is recruited to sites of specific immune reactions, including allergic reactions. These cells settle in the tissue where their number is about 100 times higher than in the blood. In tissues and when activated, eosinophils release highly basic, preformed mediators such as eosinophil peroxidase. What else do they release? Major basic protein Granzymes Bence Jones proteins Caspases Addresins

Major basic protein

There are two types of in vivo skin tests used to detect specifically sensitized T lymphocytes. The first is the intradermal test, in which antigen is injected into the skin. The second is the patch test, in which the antigen is absorbed through the skin. What is the best-known intradermal test called? Mantoux Bence Jones Lewis Duffy Kell

Mantoux

A variety of neuromuscular diseases cause symptoms of fatigue and muscular weakness. Bilateral weakness of all four limbs is usually due to a myopathy, a neuropathy, or a neuromuscular junction disorder. What is the most common neuromuscular junction disorder involving autoantibodies that attack the acetylcholine receptor on the post-synaptic membrane? Guillain-Barré syndrome Optic neuritis Myasthenia gravis Stevens-Johnson syndrome Henoch-Schoenlein purpura

Myasthenia gravis

Lipopolysaccharide (LPS), a component of the cell wall of Gram-negative bacteria, and many other microbes and their products can activate the transcription factor in lymphocytes known as what? IκB TLR NFκB CXCR4 Mac-1

NFκB

Cells infected by viruses can also signal the presence of intracellular infection by expressing on their surfaces viral proteins that can be recognized by antibodies. Cells bound by such antibodies can then be killed by a specialized lymphoid cell called a? Mast cell Eosinophil Natural killer cell Dendritic cell Macrophage

Natural killer cell

In a clinical setting, the degree of sensitivity to a particular allergen is often determined by the patient's complaints and by the extent of skin test reactions. A more quantitative assay that correlates with clinical symptoms is needed. What is an example of a test that meets these criteria? ELISA RAST PCR IEF SDS-PAGE

RAST

The laboratory you are working in is studying the regulation of immunoglobulin synthesis. You know that in order to produce the complete immunoglobulin protein, changes must occur at the DNA level. The production of complete immunoglobulin proteins occurs because of? Rearrangement of DNA in the germline Rearrangement of DNA in the B cells Splicing of RNA in B cells Deletion of immunoglobulin genes which are not needed Reorganization of large chromosome fragments in the germline

Rearrangement of DNA in the B cells

A mechanism for inactivation of autoreactive B cells in the periphery that is associated with downregulation of surface IgM is? Gene conversion Gene duplication Antigenic shift Anergy Latency

Anergy

The interaction of self-molecules and immature B cells is important in the development of self-tolerance in the B cell lineage: cells with potential reactivity to self are prevented from responding. This can happen in two ways. If an immature B cell is exposed to a self-molecule expressed on the surface of bone marrow cells, it dies by apoptosis. In contrast, if the immature B cell is exposed to a non-cell surface molecule (soluble antigen) in the bone marrow, what does the cell go into? Apoptosis Anergy Latency Persistence Tolerance

Anergy

Many human autoimmune diseases show HLA-linked disease associations and these have been defined more exactly as HLA genotyping has become more precise through polymerase chain reaction analysis of HLA allele sequences. The association of MHC genotype with autoimmune disease is not surprising, because autoimmune responses involve T cells, and the ability of T cells to respond to a particular antigen depends on MHC genotype. What is one of the most dramatic examples of all HLA-associated diseases? Autoimmune hemolytic anemia Wegener's granulomatosis Chediak-Higashi syndrome Ankylosing spondylitis Autoimmune thrombocytopenic purpura

Ankylosing spondylitis

Which of the following best defines an immunogen? Any protein or carbohydrate that enters the body Any substance that is able to combine with T or B cells A substance that binds to a specific site on the Fab fragments of antibodies A simple substance that is not immunogenic itself but can react with a specific antibody Any substance that can evoke an immune response

Any substance that can evoke an immune response

Many antiviral vaccines currently in use consist of inactivated viruses. Inactivated, or killed viral vaccines, consist of viruses treated so that they are unable to replicate. How is another type of antiviral vaccine commonly used that is usually far more potent is prepared? Molecular mimicry Anergy Attenuation Molecular pathogenesis Latency

Attenuation

Patients with hyposplenism or those who have undergone splenectomy are at risk for overwhelming pneumococcal infection. This is because an immune cell population is important in the production of protective antibody against pneumococcal cell wall and other carbohydrate antigens. This cell population consists of what splenic element? Dendritic cells Basophils Eosinophils B lymphocytes T lymphocytes

B lymphocytes

The interaction of the MHC and the T cell receptor in T cell activation is called the first signal. Additional signals, known as costimulatory or second signals, are required for full T cell activation. What glycoprotein is one of the 2 best-characterized costimulatory molecules on antigen-presenting cells? B7.1 VCAM-1 IL-8 LFA-1 IP-10

B7.1

B cells can develop a vast repertoire of antigenic specificities. B-lymphocytes arise from hematopoietic stem cells that commit to the B cell lineage in response to signals from a variety of soluble factors, and as a result of interactions with cells in their environment. Where can immature B cells interact with self-molecules? Peyer's patch Spleen Bone marrow Thymus Stroma

Bone marrow

In a laboratory, three sets of experiments have been performed on skin transplantation in mice. In set A, skin has been grafted between genetically identical mice (syngeneic graft). In sets B and C, skin was grafted between genetically unrelated mice (allograft). In set B, however, donor and recipient were MHC-identical, while donor and recipient mice of set C were different in their MHC loci. In which sets will the skin grafts be rejected rapidly, slowly, and not rejected, respectively? A, B, C C, B, A None, A, None A, C, B B, A, C

C, B, A

Inflammatory cytokines provoke increased synthesis of certain serum proteins in the liver. The proteins are known as "acute-phase proteins" and include proteins that act as mediators, enzyme inhibitors, or scavengers. The increased serum concentrations are thus helpful in inflammation. What is one of these proteins? Interleukin C-reactive protein Cyclosporine SRS-A Adjuvant

C-reactive protein

Eotaxins are CC chemokines that attract eosinophils, Th2 lymphocytes, and basophils. There are two eotaxins, eotaxin-1 and eotaxin-2, which share similar activities although they share little homology. Eotaxins are produced by epithelial cells, endothelial cells, and eosinophils, and their expression is enhanced in allergic inflammation. Thus, eotaxins are thought to play an important role in allergy and asthma. What is the receptor for eotaxins? CCR3 CCR5 CXCR4 Mac-1 SDF-1

CCR3

It is now known that T cells can recognize lipids and glycolipids in addition to protein-derived antigens. The T cell response to the lipid and glycolipid cell wall products derived from mycobacteria has been well documented. A third family of antigen-presenting molecules, distantly related to MHC class I and II molecules, has evolved to present lipid and glycolipid antigens derived from microbial pathogens to T cells. What is this family of genes and products called? CCR5 CCR3 CD1 CEA CTLA-4

CD1

Which of the following CD antigens are receptors for a co-stimulatory (secondary) signal for B cells? CD3 and CD4 CD4 and CD8 CD23 and CD95 CD44 and CD19 CD28 and CD40

CD28 and CD40

Which of the following CD antigens is typical for helper T lymphocytes? CD23 CD40 CD95 CD8 CD4

CD4

Which of the following CD antigens is typical for cytotoxic T lymphocytes? CD23 CD40 CD95 CD8 CD4

CD8

Which of the following CD antigens mediates apoptosis (programmed cell death)? CD23 CD40 CD95 CD8 CD4

CD95

The full activation of T lymphocytes takes 4 to 5 days and is accompanied by marked changes in the homing behavior of these cells. Differential expression of cell-surface molecules can direct subsets of armed effector T cells to specific sites. Cells that home to the skin, for example, express what antigen? CEA AFP LTN MAGE CLA

CLA

B lymphocyte antigen receptor signaling is modulated by a co-receptor complex of at least three cell-surface molecules that can be co-ligated with the B cell receptor. These molecules have been shown to increase the activatory signal after antigen binds to immunoglobulin on the B cell surface. One of these molecules binds iC3b and C3dg and is known as? CD4 G-CSF CEA CR2 LTN

CR2

B lymphocytes arise from hematopoietic stem cells that commit to the B cell lineage in response to signals from a variety of soluble factors and as a result of interactions with cells in their environment. Antigen binding by surface immunoglobulin is insufficient on its own to activate B cells. The activation of B cells is modulated by co-receptors, which include receptors for what? Complement Protein A Pilin Phytohemagglutinin C-reactive protein

Complement

Each B lymphocyte makes antibody of one single specificity that is fixed by the nature of gene rearrangements. During the lifetime of an individual cell, however, it can switch to make a different class of antibody, while retaining the same antigenic specificity. This is known as class or isotype switch. Class switching occurs in mature B cells and is dependent on antigenic stimulation of the cell and the presence of factors released by T cells. These factors are known as? Cytokines Immunoglobulins Caspases RANTES Selectins

Cytokines

Neutrophils (and macrophages) contain cationic peptides, which contain around 30-35 amino acids, are rich in cysteine and arginine, and have specific antibiotic-like activity by virtue of their pore-forming activity. What are these peptides called? Leukocidins Immunotoxins Immunophilins Defensins Endotoxins

Defensins

Sometimes antibodies remain present in the serum for very long periods in the absence of persistent infection or re-exposure to the antigen. For example, evidence from isolated Alaskan communities show that antibody to poliomyelitis virus persists for 40 years in the absence of possible re-exposure. An explanation for this is that antigen can persist on the surface of certain cells for long periods of time. What are these immune cells known as? Dendritic cells Macrophages Polymorphonuclear lymphocytes Stem cells Bone marrow

Dendritic cells

Solid-phase immunoassays employ the property of various plastics to adsorb monomolecular layers of proteins onto their surface. Although the adsorbed molecules may lose some of their antigenic determinants, enough remain unaltered and can still react with their corresponding antibodies. What is the most common solid phase immunoassay used? PCR IEF ELISA SDS-PAGE FACS

ELISA

Cytokines are similar to polypeptide hormones, since they facilitate communication between cells and do so at very low concentrations. Cytokines are short-lived and may act locally either on the same cell that secreted them or other cells, or, like hormones, they may act systemically. More than 25 cytokines have now been identified that exhibit some sort of hematopoietic activity. What is an example of a cytokine that is also a hormone? Gas G-CSF EPO RANTES MAGE

EPO

More than 25 cytokines identified as having some sort of hematopoietic activity. The principal factor for accelerating recovery of red blood cell mass following hemorrhage, is one of these. It is a cytokine that is also a hormone. What is this factor? Fas G-CSF RANTES MAGE EPO

EPO

Many cytokines, including tumor necrosis factor (TNF), activate functions of inflammatory cells. During localized acute inflammatory responses, this cytokine causes increased vascular permeability, which ultimately leads to the swelling and redness associated with inflammation. TNF-α is secreted by macrophages and monocytes following their stimulation by what? RTX toxin Endotoxin Immunotoxin Immunophilins Toxoids

Endotoxin

Leukocyte adhesion is of pivotal importance in leukocyte physiology. If leukocytes cannot adhere to other leukocytes or various target cells, B lymphocytes cannot synthesize immunoglobulins, T cells and NK cells are not cytotoxic, and neutrophils show no phagocytosis or chemotaxis. Some of the most important adhesion molecules are the ICAMs. One of these was found to act as a major rhinovirus receptor and as a receptor for Plasmodium falciparum-infected red cells. What is this molecule? ICAM-1 ICAM-2 ICAM-3 ICAM-4 ICAM-5

ICAM-1

There are many chronic diseases in which infection persists because of a failure of the immune system to eliminate disease. Hepatitis B and hepatitis C infections are commonly followed by persistent viral carriage and hepatic injury, resulting in ultimate death from hepatitis or from hepatoma. A number of clinical trials have shown what as an effective treatment for patients with chronic hepatitis B infection? LTN CEA AFP MAGE IFN

IFN

Which of the following interferons (IFN) is secreted by Th1 cells and cytotoxic T lymphocytes, and activates macrophages and natural killer (NK) cells? IFN-α IFN-β IFN-γ All interferons, including -α, -β, and -γ

IFN-γ

When an immune response is initiated, it is controlled by a combination of stimulatory and inhibitory influences, including cytokines. Cytokines are small soluble proteins secreted by one cell that can alter the behavior or properties of the cell itself or of another cell. They are released by various cells of the immune system, in a cascade during the response to antigen. Most cytokines have a multitude of different biological effects when tested in biological assays in vitro. Th1 cells are associated with delayed-type hypersensitivity (DTH) reactions resulting in the recruitment and activation of macrophages. Th1 cells are characterized by the expression of what? IL-4 and IL-5 IL-1 and IL-18 GM-CSF and TGF-β IL-2 and IFN-γ IL-6 and IL-2

IL-2 and IFN-γ

Eosinophils are bone marrow derived granulocytes that express Fc receptors when they are recruited to an inflammatory site. Only very small numbers of these cells are normally present in the circulation; most eosinophils are found in tissues, especially in the connective tissues immediately underneath respiratory, gut, and urogenital epithelium, implying a likely role for these cells in defense against invading organisms. What is an important regulator of the growth, survival, and function of eosinophils? Fas receptor IL-5 G-CSF IL-8 RANTES

IL-5

What is a powerful chemoattractant for neutrophils? Fas G-CSF IL-8 RANTES MAGE

IL-8

Which of the following immunoglobulin isotypes can be found in mucus secretions? IgA IgE IgG1 IgG4 IgM

IgA

For which of the following immunoglobulin isotypes are Fc receptors present on the mast cells? IgD IgE IgG1 IgG4 IgM

IgE

Which of the following antibodies is protective against reinfection with hepatitis A virus (HAV)? HBsAb HBeAb HBcAb IgM-HAVAb IgG-HAVAb

IgG-HAVAb

B-1 cells are characterized by the surface expression of CD5 and what? IgM IgA IgG IgD IgE

IgM

Which of the following immunoglobulin isotypes is the strongest activator of the complement system? IgD IgE IgG1 IgG4 IgM

IgM

Macrophage colony-stimulating factor (M-CSF) utilizes what family of cytokine receptors? Immunoglobulin superfamily Class I TNF MAGE Ras

Immunoglobulin superfamily

Glucocorticoids can suppress the immune response. These steroids affect the development of the manifestations of the inflammatory response whether the inciting agent is radiant, mechanical, chemical, infectious, or immunological. They are useful in treating diseases that result from undesirable immune reactions from urticaria to autoimmune disease to transplant rejection. What do therapeutic doses of glucocorticoids do? Decrease the concentration of circulating antibodies by reducing the expression of CD19 and CD20 antigens Prevent the initial interaction of antigen with B cells by down-regulating cell surface CD5 Inhibit the assembly of antigen peptide-MHC complexes on the surface of antigen-presenting cells Block transcription of early T cell activation genes, such as the one for CD40, required for T cell proliferation Inhibit the elaboration and action of local mediators such as lymphokines and prostaglandins

Inhibit the elaboration and action of local mediators such as lymphokines and prostaglandins

A 14-year-old boy is evaluated for dyspnea and a productive cough. He was born in Mexico and has a history of chronic diarrhea, anemia, and weight loss. When he was 10, a rectal biopsy showed granulomas. He was initially treated for a presumed diagnosis of intestinal tuberculosis and later for Crohn's disease. Chest X-ray shows consolidation of the right lung with a large abscess. Sputum is positive for Aspergillus fumigatus. Despite intravenous amphotericin B and oral itraconazole, his condition deteriorates. A nitroblue tetrazolium test result is negative. Despite intensive therapy, including transfusions of normal granulocytes, he develops respiratory failure and dies in the intensive care unit. Question What type of immune response was defective in this patient? Innate Acquired Humoral Cellular Self-tolerance

Innate

All T lymphocytes express a molecule known as lymphocyte function-associated antigen-1 (LFA-1). This is thought to be the most important adhesion molecule for lymphocyte activation because antibodies to it effectively inhibit the activation of both native and armed effector cells. LFA-1 is up-regulated by T cell activation and is a member of a family of cell-surface proteins known as what? Streptolysins Immunophilins Interleukins Selectins Integrins

Integrins

Mac-1, also called CD11b/CD18, is stored in specific granules that are shuttled to the granulocyte surface. It exists as a chemoattractant activation-dependent molecule that undergoes a conformational change upon stimulation. Expression of new epitopes on Mac-1 can be detected after activation using monoclonal antibodies. Antibodies to a subunit of Mac-1 also abrogate granulocyte adhesion to a variety of substrates including fibrinogen, fibronectin, and albumin. Mac-1 belongs to what family of molecules? Streptolysins Integrins Immunophilins Interleukins Selectins

Integrins

VLA-4 antagonists are a new class of compounds that has shown promise in animal models of asthma. This is based on the understanding that VLA-4 acts as a homing receptor for vascular endothelium in sites of inflammation and ensures that activated T cells recirculate through peripheral tissues where they may encounter sites of infection. All of the VLA molecules are members of what family of glycoproteins? Selectins Integrins Streptolysins Immunophilins Interleukins

Integrins

The immune response to even a simple antigen is diverse, comprised of many different antibody molecules each with a unique affinity and fine specificity. The complete collection of antibody specificities available within an individual is enormous and is known as the "antibody repertoire." Antibodies containing small differences in amino acid composition can be distinguished on the basis of their charge. What is a simple method for doing this? Equilibrium dialysis Isoelectric focusing SDS-PAGE ELISA FACS

Isoelectric focusing

The first antibodies to be produced in an immune response are always IgM. These early IgM antibodies are produced before B cells have undergone somatic hypermutation and therefore tend to be of low affinity. Why is IgM is usually confined to the blood? Its charge Its affinity Its size Its amount Its specificity

Its size

Immunoglobulin gene rearrangement is dependent on the expression of certain genes. What is one of these called? VLA-4 Mac-1 LFA-1 ICAM-1 RAG-1

RAG-1

Eosinophils are bone marrow-derived granulocytic leukocytes, so named because their granules (which contain arginine-rich basic proteins), are colored bright orange by the acidic stain, eosin. Only very small numbers of these cells are normally present in the circulation; most eosinophils are found in tissues, especially in the connective tissue immediately beneath respiratory, gut, and urogenital epithelium, implying a likely role for these cells in defense against invading organisms. An abnormal chest X-ray, accompanied by a rise in the number of eosinophils in the blood, may indicate the presence of a form of inflammation called acute pulmonary eosinophilia, also known as? Polyarthritis nodosa Loeffler's syndrome POEMS syndrome Alport syndrome Glanzmann's thrombasthenia

Loeffler's syndrome

The clonal selection theory is one of the pivotal concepts in immunology. If you were to coat glass beads with an antigen to which the lymphocytes of an animal had never been exposed, pass the lymphocytes through a column packed with such beads, and to collect the effluent lymphocytes from the column, then the clonal selection theory would predict that? Lymphocytes in the effluent would not bind the bead antigen Lymphocytes in the effluent would bind the bead antigen Lymphocytes in the effluent would bind to each other Lymphocytes left on the column would not bind antigen Lymphocytes left on the column would non-specifically bind the glass beads

Lymphocytes in the effluent would not bind the bead antigen

Members of the cytokine family fall into two broad groups - CC chemokines with two adjacent cysteines, and CXC chemokines, in which the equivalent two cysteine residues are separated by another amino acid. The two groups of cytokines act on different sets of receptors and different cell types; in general, the CXC chemokines promote the migration of neutrophils, whereas the CC chemokines promote the migration of monocytes or other cells types. What is an example of a CC chemokine? VCAM-1 MCP-1 Mac-1 LFA-1 ICAM-1

MCP-1

The CD8+ T cells recognize antigenic peptides presented by? Complement system MHC I MHC II MHC III Red blood cells surface proteins

MHC I

The HLA-A, HLA-B, and HLA-C proteins belong to? Complement system MHC I MHC II MHC III Red blood cells surface proteins

MHC I

The discovery of major histocompatibility complex (MHC) restriction helped explain the phenomenon of non-self MHC recognition in graft rejection. Transplanted tissues from donors bearing MHC molecules that differ from those of the recipient are reliably rejected. The rapid and potent cell-mediated response to the transplanted tissue results from the presence in any individual of large numbers of T cells that are specifically reactive to particular non-self or allogeneic MHC molecules. Early studies on T cell responses to allogeneic MHC molecules used what technique? ELISA PCR IEF FACS MLR

MLR

The expression of the immune response involves a certain amount of inflammation, cell infiltration, lymph node swelling, and even tissue destruction. Sometimes they are very severe. There are signs of an immune response in nearly all infections. Therefore, it is to be expected that there will nearly always be some contribution of the immune response to pathological changes. Sometimes this forms the major part of the disease. For example, in tuberculosis, much of the lung tissue damage is caused by the release of destructive enzymes by what? Mast cells Eosinophils Dendritic cells Basophils Macrophages

Macrophages

Many of the microbes that are most important in human infectious diseases multiply in the extracellular spaces of the body. Most intracellular pathogens must spread by moving from cell to cell through the extracellular fluids. Viruses and intracellular bacteria, which need to enter cells in order to grow, spread from cell to cell by binding to specific molecules on their target cell surface. Antibodies that bind to the pathogen can prevent this. What is this process, which is also important in protection from bacterial toxins, called? Opsonization Neutralization Phagocytosis Pinocytosis Endocytosis

Neutralization

The migration of leukocytes out of blood vessels, a process known as extravasation, is thought to occur in steps. In one step, the leukocyte extravasates, or crosses, the endothelial wall. This involves what immunoglobulin-related molecule? PECAM-1 Mac-1 LFA-1 VLA-4 L-selectin

PECAM-1

The rash produced by poison ivy, is caused by a T cell response to a chemical in the poison ivy leaf. As the chemical is delivered by contact with the skin, this is called "contact dermatitis". An important test in determining which antigen is responsible for contact dermatitis is? Patch test Isoelectric focusing SDS-PAGE ELISA FACS

Patch test

The principal mechanism through which cytotoxic T cells act is by the calcium-dependent release of specialized lytic granules upon recognition of antigen on the surface of a target cell. These granules are modified lysosomes that contain at least two distinct classes of cytotoxic effector protein that are expressed selectively in cytotoxic T cells. Such proteins are stored in the lytic granules in an active form, but conditions within the granules prevent them from functioning until after their release. One of these cytotoxic proteins polymerizes to generate transmembrane pores in target cell membranes. What is it called? Perforin Opsonin Immunophilin Leukocidin RTX toxin

Perforin

Since antibodies bind stably and specifically to antigen, they are invaluable as probes for identifying a particular molecule in cells, tissues, or biological fluids. The bound antibody can be visualized with a variety of sensitive techniques, and the specificity of antibody binding coupled to sensitive detection provides remarkable detail about the structure of cells. Immunofluorescence is one of these techniques. What is a widely used fluorescent compound that can be easily coupled to free amino acid groups on antibodies that fluoresces red? Fluorescein isothiocyanate Phycoerythrin Immunophilin Phytohemagglutinin Protein A

Phycoerythrin

A medical student is investigating a response of white blood cells to the bacterial infection. He starts with microscopic investigation of the paronychia in a 55-year-old man. The first thing he sees is a leucocyte propelling the membrane at its leading edge. The student is fascinated and asks you how it happens. Question How will you explain phagocytosis in terms of basic active mechanism underlying this first movement of the leading edge? Traction force Stall force Polymerization Active transport Adhesion

Polymerization

An antigen can be defined as any foreign molecule that will stimulate antibody formation when offered appropriately to the host. The newly-formed antibody will react specifically to the immunizing antigen. The most immunogenic chemical family is? Carbohydrates Lipids Nucleic acids Haptens Proteins

Proteins

The major histocompatibility complex (MHC) of genes consists of a linked set of genetic loci encoding many of the proteins involved in antigen presentation to T cells, most notably the MHC glycoproteins that present peptides to the T cell receptor. The outstanding feature of MHC genes is their extensive polymorphism. Most MHC alleles differ from one another by multiple amino acid substitutions, and these differences are focused on the peptide-binding site and adjacent regions that make direct contact with the T cell receptor. New MHC alleles can be created when DNA segments are exchanged between different chromosomes. What is this called? Gene duplication Recombination Gene conversion Antigenic shift Antigenic drift

Recombination

One family of adhesion molecules induces "rolling" of leukocytes along blood vessel walls, an important first step in adhesion. What is this family known as? Integrins Selectins Streptolysins Immunophilins Interleukins

Selectins

Superantigens have a distinctive mode of binding to MHC molecules that enables them to stimulate large numbers of T cells. This binding event causes massive production and secretion of cytokines by CD4 T cells. What is an example of a superantigen? CTLA-4 Integrin Streptolysin Staph enterotoxin CD28

Staph enterotoxin

Autoimmune diseases such as Type 1 diabetes, RA, and MS are common, often devastating diseases. The key feature of these diseases is the development and persistence of inflammatory processes in the apparent absence of pathogens, leading to destruction of the target tissue. Presently no comprehensive explanation can be given for the onset of autoimmune disease. As a rule, the chronic activation of a particular type of cell appears to be crucial for fueling the destructive autoimmune processes. What is this cell type? T helper cells T suppressor cells Macrophages Dendritic cells Basophils

T helper cells

A 44-year-old man has been feeling "unwell" the entire week. He complains of anorexia and nausea. On Saturday morning he finds darkening of his urine to a brownish color. His labs confirm the suspicion of acute viral hepatitis. Screening serologic studies for hepatitis A and B virus (HAV, HBV) infections show: IgM anti-HAV Ab negative HBV surface Ag positive IgM anti-HBV core Ab positive Anti-HBV surface Ab negative Which of the following mechanisms best explains the hepatic injury? Direct injury of hepatocyte membranes by viral surface antigen Inhibition of hepatocyte DNA replication Inhibition of hepatocyte mRNA translation Hepatocyte lysis by cytotoxic IgM antibody to viral core antigen T lymphocyte-mediated lysis of infected hepatic cells Allergic reaction to the viral proteins

T lymphocyte-mediated lysis of infected hepatic cells

The response of macrophages to pathogenic stimuli is an important first step in innate immunity and plays an important part in the ultimate success or failure of an organism's attempt to resist pathogenic infection. Macrophages recognize pathogens by a diverse family of pattern recognition receptors. What activates the expression by macrophages of a variety of cytokines and co-stimulatory molecules crucial to adaptive immunity? CXCR4 Mac-1 SDF-1 TLR-4 IL-8

TLR-4

The major function of CD8 T cells is to kill cells that have been infected by pathogens, such as bacteria and viruses. CD8 T cells are frequently referred to as T killer or cytotoxic T lymphocytes (CTL). The cell killed by a CTL is known as a target. An important pathway of target cell killing occurs via the interaction of the molecule Fas ligand on the activated CTL with Fas on the target cell. Fas is a ligand associated with what receptor family? CEA AFP TNF MAGE Ras

TNF

Cytokines are similar to polypeptide hormones, since they facilitate communication between cells and do so at very low concentrations. Cytokines are short-lived and may act locally either on the same cell that secreted them or other cells, or, like hormones, they may act systemically. More than 25 cytokines have now been identified that exhibit some sort of hematopoietic activity. Several have been identified with stimulatory activity on platelet production. What is one of these? EPO G-CSF M-CSF TPO RANTES

TPO

Which of the cell types listed below is the best producer of Interleukin-4 (IL-4)? CD3+CD8+ Th1 cells Macrophages B cells Th2 cells

Th2 cells

IgE is mostly found fixed in the tissues on mast cells that bear receptors for it, as well as on circulating basophils and activated eosinophils. The ligation of cell-bound IgE by antigens such as pollen or mold triggers activation of these cells at the site of antigen entry into the tissues. The release of inflammatory lipid mediators, cytokines, and chemokines at sites of IgE-triggered reactions results in the recruitment of eosinophils and basophils to augment what response? Wheal-and-flare reaction Type I hypersensitivity Type II hypersensitivity Type III hypersensitivity Urticaria

Type I hypersensitivity

Allergy to nickel is a well-known cause of contact dermatitis. Patches of dermatitis under a watch or on earlobes suggest that a patient should be patch-tested with a battery of commonly implicated agents, including nickel and chromate. Of what is nickel dermatitis an example? Wheal-and-flare Type II hypersensitivity Type III hypersensitivity Type IV hypersensitivity Urticaria

Type IV hypersensitivity

Leukocyte adhesion is of pivotal importance in leukocyte physiology. If leukocytes cannot adhere to other leukocytes or various target cells, B-lymphocytes cannot synthesize immunoglobulins, T cells and NK cells are not cytotoxic, and neutrophils show no phagocytosis or chemotaxis. One family of adhesion molecules is the integrins. Integrins are αβ-heterodimers that recognize extracellular matrix and cell surface glycoproteins, as well as some soluble molecules such as complement factor C3bi. The most important member of the β1 integrin subfamily on leukocytes is one that is induced by T cell activation. What is it called? Mac-1 VLA-4 ICAM-1 ICAM-2 ICAM-3

VLA-4

The laboratory you are working in is studying the regulation of immunoglobulin synthesis. You know that in order to produce the complete immunoglobulin protein, changes must occur at the DNA level. The antigen binding site of the immunoglobulin molecule is contained in the? Constant region Variable region Fc fragment Heavy chain only Hinge region

Variable region

Interferons are cytokines, members of a family of cell-regulatory proteins produced by all vertebrates. There are three types of interferon: alpha, beta, and gamma. Alpha and beta interferons are very similar, and are encoded on chromosome 9. What are the most important inducers of interferon alpha and beta? Mast cells Eosinophils Dendritic cells NK cells Viruses

Viruses


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