Micro Chapter 13 Weaver

Which of the following serve as professional antigen-presenting cells expressing both MHC class I and MHC class II? (select all that apply) A. T cells B. B cells C. Macrophages D. Dendritic cells E. Neutrophils

B. B cells C. Macrophages D. Dendritic cells

Which cells are responsible for the humoral component of adaptive immunity? A. Macrophages B. B lymphocytes C. T lymphocytes D. Neutrophils

B. B lymphocytes

Which of the following is an example of herd immunity? A. The disease Brucellosis has been eradicated from farm animals in the U.S. B. If 80% or more of the cattle population is immune to Brucellosis, the disease will be essentially absent from the population C. Federal law requires that all cattle not immune to anthrax be destroyed. D. All farm animals used for food must be immunized against all common agents of disease that infects humans.

B. If 80% or more of the cattle population is immune to Brucellosis, the disease will be essentially absent from the population

In general, which of the following vaccine strategies/types has the best efficacy but the greatest risks for adverse effects in the patient. A. Killed/Inactivated B. Live Attenuated C. Subunit D. Conjugate

B. Live Attenuated

Intracellular proteins can be degraded into peptides by the proteasome and then presented on ______________ to CD8-positive T cells. A. TLR2 B. MHC class I C. MHC class II D. MHC class III

B. MHC class I

A T helper cell (CD4 T cell) can promote killing of bacteria by activating macrophages that are presenting bacterial antigens on ____________ molecules. A. MHC class I B. MHC class II C. TCR D. PRR

B. MHC class II

Which type of helper T cell response would be best at clearing your body of an infection by a parasitic roundworm or flatworm? A. TH1 B. TH2 C. TH17 D. TR

B. TH2

Once you have acquired immunity to a specific pathogen, either through natural or artificial (vaccine) means, are you protected from ...? A. infection/colonization by that pathogen B. disease caused by that pathogen

B. disease caused by that pathogen

An activated TH cell produces ________, which is a growth factor for clonal expansion of both helper T cells and cytotoxic T cells. A. interleukin-1 B. interleukin-2 C. interleukin-12 D. antiserum

B. interleukin-2

Which process involves antibodies coating microorganisms in order to facilitate phagocytosis? A. neutralization B. opsonization C. complement fixation D. agglutination

B. opsonization

What determines whether an activated CD4 T cell will differentiate into either a TH1, TH2, or TH17 effector cell? A. the type of antigen (protein, carbohydrate, lipid) being presented B. the types of PAMPs and the resulting cytokines produced C. the affinity the T cell has for the antigen D. the type of APC that is doing the stimulation (dendritic cell, macrophage, or mast cell).

B. the types of PAMPs and the resulting cytokines produced

chickenpox vaccine which triggers extended immunity to chickenpox

Artificial active

giving a person immune serum globulins to chickenpox virus after exposure to the disease

Artificially passive

How many antigen binding sites are there on one IgG molecule?

2

Which of the following is the most important APC in the priming of naive T cell responses? A. dendritic cells B. B cells C. M cells D. macrophages

A. dendritic cells

T helper cell 1 (Th1)

Activates the cell-mediated immunity pathway; secretes TNF and interferon gamma; responsible for delayed hypersensitivity; CD4 receptors expressed

Which type of helper T cell response would be best at clearing your body of an infection by a facultative intracellular bacteria pathogen like Shigella flexneri or Listeria monocytogenes? A. TH1 B. TH2 C. TH17 D. TR

A. TH1

In an adaptive immune response, the activation of which of the following cells would lead to enhanced macrophage activation? A. TH1 cells B. TH2 cells C. TH17 cells D. NK cells

A. TH1 cells

Which of the following best describes the mechanism by which B lymphocytes become activated to release antibodies specific against a particular pathogen? A. The foreign antigen activates its counter-specific cell from a pre-existing pool of B cells. The particular B cell is then induced to multiply (producing its clones) for antibody production. This process can be facilitated by helper T cells. B. The foreign antigen elicits the creation of a cognate BCR from precursor genes in a lymphoid stem cell in the bone marrow. The newly made B cell is then induced to multiply (producing its clones) for antibody production. C. The foreign antigen turns on the process of hematopoiesis to develop immature B cells that can bind to that antigen. B cell hematopoiesis will be halted once the foreign antigen has been cleared from the body. D. The foreign antigen is first processed and presented by antigen presenting cells (APCs). The APCs then prime the activation of a particular type of T cell that has the capacity to differentiate into an antibody secreting B cell.

A. The foreign antigen activates its counter-specific cell from a pre-existing pool of B cells. The particular B cell is then induced to multiply (producing its clones) for antibody production. This process can be facilitated by helper T cells.

Which of the following is a substance that enhances immunogenicity and prolongs antigen retention at the injection site? A. adjuvant B. booster C. antibodies to toxin D. gamma globulin

A. adjuvant

The Haemophilus influenzae vaccine that has reduced the incidence and severity of childhood meningitis caused by this bacterium is a conjugate vaccine. This vaccine is made by coupling H. influenzae __________ to _________ so as to stimulate T-dependent antibody responses. A. capsular polysaccharide / a protein carrier B. capsular polysaccharide / peptidoglycan C. envelope protein / irradiated DNA D. envelope protein / an adjuvant

A. capsular polysaccharide / a protein carrier

During lymphocyte maturation, the destruction of lymphocytes with self-antigen specificity is called: A. clonal deletion B. proliferation C. clonal selection D. differentiation.

A. clonal deletion

This leukocyte is named for its long, thin processes that can take up extracellular antigens via endocytosis and present them to naive T cells in order to activate them. A. dendritic cell B. eosinophil C. macrophage D. mast cell

A. dendritic cell

Cytotoxic T cells are important in the host defense from: A. intracellular pathogens (viruses and certain bacteria, yeast, protozoa) B. extracellular microbes in the body tissues C. exotoxins D. All of the above E. None of the above

A. extracellular bacteria cells

Which of the following is not a target for killing by TC cells? A. extracellular bacteria cells B. virus-infected host cells C. cancer cells D. transplanted human liver cells E. intracellular bacteria-infected host cells

A. extracellular bacteria cells

Which process involves antibodies covering surface receptors on a virus or toxin molecule thereby disrupting their activity? A. neutralization B. opsonization C. complement fixation D. agglutination

A. neutralization

Naive T cells require 3 major signals in order to become activated effector T cells. One of these signals is the cognate antigen for that T cell. The second is referred to as co-stimulation. What message is co-stimulation sending? A. presence of PAMPs (danger signal) in the tissues B. presence of foreign antigen in the tissues C. presence of self-antigen in the tissues D. presence of resident commensal microbiota in the body E. sorry, foreign antigen is sufficient to activate a naive T cell

A. presence of PAMPs (danger signal) in the tissues

Which of the following types of macromolecules could be an antigen for both T cells and B cells? A. protein B. nucleic acid C. polysaccharide D. phospholipid E. lipopolysaccharide

A. protein

After maturation, B and T cells migrate to the periphery, recirculate, and reside in lymphoid organs including the ____________. A. spleen and lymph nodes B. thymus and bone marrow C. lymph vessels and blood D. thymus and spleen

A. spleen and lymph nodes

Which portion is different (variable) between IgG antibodies? A. the antigen binding site B. the Fc region C. the hinge region D. the heavy chain

A. the antigen binding site

Which of the following determines whether a T cell will be activated to become a TH1 or TH2 cell? A. the type of PAMPs present and the cytokines produced B. the type of antigen (protein, carbohydrate, or lipid) C. the affinity the T cell has for the antigen D. the type of APC that is doing the stimulation (dendritic cell, macrophage, or mast cell

A. the type of PAMPs present and the cytokines produced

A fetus acquiring maternal IgG to the chickenpox virus across the placenta

An example of natural passive immunity would be:

What are allergens?

Antigens that produce an allergic response

IgM

B cell receptor on mature B cells, Secreted form predominates early in immune responses; activates complement

What directs B cell antibody class switching from IgM to either IgG, IgA, or IgE? A. Some B cells just randomly start to recombine their heavy chain genes to switch classes. B. B cells respond to complement protein C3 and begin to class switch. C. B cells are directed to class switch in response to specific cytokines made by helper T cells. D. TNF and IL-1 made my PAMP-triggered macrophages induce B cells to class switch.

C. B cells are directed to class switch in response to specific cytokines made by helper T cells

The immunoglobulin class with an Fc region that binds to receptors on basophils and mast cells: A. IgA B. IgD C. IgE D. IgG E. IgM

C. IgE

Antigens derived from extracellular pathogens can be taken in by endocytosis and presented on _______ to CD4 T cells. A. TLR4 B. MHC class I C. MHC class II D. MHC class III

C. MHC class II

Which of the following describes a difference between T cells and B cells? A. Express an antigen receptor B. Undergo negative selection (clonal deletion) resulting in self-tolerance C. Require antigen to be presented in the context of a host MHC molecule D. Undergo clonal expansion during activation E. Can produce immune memory cells

C. Require antigen to be presented in the context of a host MHC molecule

Which cells are responsible for the cell-mediated component of adaptive immunity? A. Macrophages B. B lymphocytes C. T lymphocytes D. Neutrophils

C. T lymphocytes

Which type of helper T cell response would be best at activating neutrophils to clear the body of an extracellular bacterial or yeast infection in the mucosae? A. TH1 B. TH2 C. TH17 D. TR

C. TH17

The transient swelling of lymph nodes during an infection is largely due to: A. complement activation B. growth of bacterial cells C. clonal expansion of B and T cells D. influx of large numbers of neutrophils

C. clonal expansion of B and T cells

Which of the following does not describe an effector function of antibodies in combating infections? A. preventing pathogens from binding to host cells B. enhancing phagocytosis by phagocytes C. entering inside host cells and inhibiting virus maturation D. activating the complement system E. antibody-dependent cell-mediated cytotoxicity

C. entering inside host cells and inhibiting virus maturation

All of the following describe effector functions of activated cytotoxic T cells EXCEPT: A. killing virus-infected host cells B. killing host cells infected with intracellular bacteria C. killing extracellular bacteria D. secreting inflammatory cytokines like IL-2 and IFN-gamma E. killing foreign cells such as with tissue transplants or cancer cells.

C. killing extracellular bacteria

T regulatory cells

Controls specific immune response; prevents autoimmunity; CD4 receptors expressed

In the question above, which of the macromolecules listed could be an antigen for B cells? A. A only B. A and B C. A, B, and C D. All of them could be, provided they were foreign to the host.

D. All of them could be, provided they were foreign to the host

The immunoglobulin class that is capable of crossing the placenta is: A. IgA B. IgD C. IgE D. IgG E. IgM

D. IgG

You read the following statement in a news article: "Many researchers believe that an effective vaccine for the HIV virus will have to induce a strong cell-mediated immune response in addition to a humoral immune response." You understand that a cell-mediated immune response refers to one that activates ... A. B cells and antibodies B. Complement C. NK cells and Interferon D. TH1 and Cytotoxic T cells E. Lysozyme and Antibacterial peptides

D. TH1 and Cytotoxic T cells

During lymphocyte maturation, what is the fate of an immature lymphocyte bearing an antigen receptor that binds strongly to a self-antigen? A. survival. B. proliferation. C. activation. D. apoptosis

D. apoptosis

Antitoxins ... A. contain modified bacterial exotoxin molecules. B. are always genetically engineered. C. contain select antigenic components of a pathogen rather than whole cells or viruses. D. confer passive immunity

D. confer passive immunity

It is thought that for successful vaccines able to protect against HIV/AIDs, tuberculosis, malaria, and hepatitis C, the vaccines will have to ... A. be live, attenuated vaccines. B. be DNA vaccines. C. elicit strong humoral immunity but not necessarily strong cell-mediated immunity. D. elicit strong cell-mediated immunity

D. elicit strong cell-mediated immunity

Mutations that arise during pathogen growth can alter _________, thereby leading to antigenic variation and evasion of the adaptive immune response. A. PAMPs B. haptens C. MHC proteins D. epitopes E. cytokines

D. epitopes

Which of the following pathogens is best combated with a host TH2 response? A. intracellular bacteria B. extracellular bacteria C. viruses D. helminths E. tumor cells

D. helminths

One attribute of specific immunity that distinguishes it from innate immunity is the production of ________ that provide long-lasting protection to the same pathogen. A. effector cells B. plasma cells C. cytotoxic cells D. memory cells E. phagocytic cells

D. memory cells

The MHC genes are highly polymorphic. When we compare the gene sequences of alleles for a specific isotype, we find that the amino acid sequences unique to each allele represent regions of hypervariability. This hypervariability occurs in which part of the MHC protein? A. cytoplasmic tail B. transmembrane domain C. CD4/CD8 binding domain D. peptide binding groove

D. peptide binding groove

The progeny cells of a B cell clone that are activated and secreting antibodies are called: A. antibodies B. sensitized T cells C. activated macrophages D. plasma cells.

D. plasma cells.

MHC molecules are found on each of the following cells except: A. leukocytes B. eosinophils C. epithelial cells D. red blood cells.

D. red blood cells.

T-cytotoxic cells:

Destroys a target foreign cell by lysis; involved in graft rejection, CD8 receptors expressed

T helper cell 2

Drives B-cell proliferation; secretes IL-4, IL-5, and IL-13; CD 4 receptors expressed

The major histocompatibility complex proteins function in: A. antigen presentation B. self/non-self discrimination C. T cell activation D. T cell maturation E. All of the choices are correct.

E. All of the choices are correct.

All of the following are characteristics of IgM except: A. secreted antibody has 10 antigen binding sites B. can activate complement C. is the first class synthesized by plasma cells D. membrane-bound form serves as a B-cell receptor E. effective in opsonization

E. effective in opsonization.

IgD

Found on surface of mature B cells; not secreted significantly; unclear function

IgG

Most abundant Ig in serum; best at diffusing from blood into tissues; good at neutralization, opsonization, and complement activation

IgA

Most abundant in mucosal tissues; dimer form found in mucus, saliva, colostrum, and other body secretions; good at neutralization but not complement activation

chickenpox infection followed by life-long immunity

Natural active

T helper cell 17

Promotes inflammation; secretes IL-17; CD4 receptors expressed

IgE

Secreted during TH2 responses; good at activating mast cells and basophils, drives allergic responses and expulsion of helminths

What are superantigens?

These molecules are not digested and processed by an APC. Result in the activation of large populations of T lymphocytes, regardless of antigen specificity. Induces an excessive production of cytokines, results in a systemic inflammatory reaction, including fever, low blood pressure, and, potentially, fatal shock. Examples: Bacterial toxins from Staphylococcus aureus and Streptococcus pyogenes and some viruses.

Antigen

a toxin or other foreign substance that induces an immune response in the body, especially the production of antibodies.

adaptive immunity

immunity or resistance to a specific pathogen; slower to respond, has memory component

Epitope (antigenic determinant)

the small, accessible portion of an antigen that binds to an antigen receptor

Killed or inactivated vaccines are prepared by

treatment with formalin, heat, or radiation.