Immunology Test 1 Practice Questions Fall 2010 Flashcards
Nitric oxide, a potent microbicidal agent, kills ingested microbes present in the phagolysosome of this phagocytic cell.
Macrophage
A synonym for secondary lymphatic organ.
Peripheral lymphatic organ
Regions in both the alpha and beta chains contribute to the polymorphism of this MHC molecule.
MHC-2
Mature T cells populate the paracortex of this lymphatic organ.
Lymph node
The major function of this cytokine is promoting thymocyte development in the thymus.
IL-7
Alternative C3 convertase.
C3bBb
Human RBC antigens exemplify these types of antigens
Alloantigens
The source of bradykinin, a vasoactive peptide of inflammation
Plasma
Interaction of these cell adhesion molecules leads to firm leukocyte/endothelium binding
Integrin/Ig superfamily CAM
pH is an important physiologic defense against microorganisms. This pH range inhibits microbial colonization of the skin
pH 3-5
T or F: Class II MHC molecules are expressed on all nucleated cells.
F
T or F: Innate immune responses operate independently of adaptive immune responses
F
T or F: Neutrophils are usually the first leukocytes to arrive at a site of inflammation.
T
T or F: The biological activities of cytokines include pleiotropy and redundancy.
T
T or F: CC subgroup chemokines are also called alpha-chemokines.
F
T or F: Antigenic peptide is added to the binding cleft of class II MHC molecule in the endosome.
T
T or F: A major function of the membrane attack complex is the lysis of Gram-positive bacteria.
F
T or F: Antigenic cross-reactivity occurs if two or more different antigens share an identical or very similar epitope.
T
T or F: Cardinal signs of acute inflammation include swelling, pain and fever.
F
T or F: During hematopoiesis, a multipotent stem cell differentiates to give rise to either a myeloid progenitor cell or a lymphoid progenitor cell.
T
T or F: Repeated exposure to an antigen leads to stronger innate and adaptive immune responses.
F
T or F: During the acute phase response, various antimicrobial proteins are released from the liver into the bloodstream.
T
T or F: Langerhans cell captures antigen that invades the skin, migrates to a regional lymph node where it matures to become a dendritic cell that can present anti-genic peptides to T cells.
T
T or F: An individual expresses up to six class I MHC proteins on his /her cells.
T
T or F: Peyer’s patches in humans function either as central lymphatic organ and/or peripheral lymphatic organ.
F
T or F: Initiators of the alternative complement pathway include lipopolysaccharide of Gram-negative bacteria and teichoic acid of Gram-positive bacteria.
T
T or F: Nucleated cells can internalize cell bound C5b678 complex, thus limiting by-stander lysis of host cells.
T
T or F: Haptens cannot evoke immune responses unless they are coupled to high-molecular-weight carriers.
T
Lipid-derived vasoactive mediators of inflammation include all of the following except
a. platelet-activating factor.
b. leukotriene C4.
c. histamine.
d. prostaglandin D2.
c
Regarding host normal flora, which of the following statements is inaccurate?
a. Bacteria constitute majority of the normal flora.
b. They protect the host against colonization by pathogenic microbes by com-peting for nutrients.
c. They produce antimicrobial substances that are harmful to incoming patho-gens.
d. The normal flora is acquired during development in the uterus.
d
Chemotactic agents that recruit leukocytes to sites of microbial invasion include all of the following except
a. lipopolysaccharide.
b. C5a.
c. chemokines.
d. leukotriene B4.
a
Which cell expresses pattern recognition receptors?
a. Macrophage
b. B cell
c. T cell
d. All of the above
a
Regarding interleukin-1, which of the following statements is least accurate?
a. The major source of interleukin-1 is the activated macrophage.
b. IL-1 receptor antagonist is an endogenous modulator of IL-1 activity.
c. The endocrine activity of IL-1 is the major function of IL-1a.
d. IL-1 stimulates acute phase protein synthesis.
c
Which lymphatic organ does not involute?
a. Bursa of Fabricius
b. Bone marrow
c. Thymus
d. Ileal Peyer’s patch
b
Components of innate immunity include all of the following except
a. epithelial barriers.
b. antibody.
c. phagocytes.
b
Each of the following plays a critical role in the endosome pathway of antigen processing and presentation except
a. invariant chain.
b. class II MHC protein.
c. Class I MHC protein.
d. HLA-DM protein.
c
This complement fragment promotes macrophage adherence to surfaces, hence limiting its ability to migrate away from the site of microbial invasion.
a. C3b
b. C5a
c. Factor P
d. Bb
d
Regarding neutrophils, which of the following statements is accurate?
a. Neutrophils have the capacity to present antigen to T cells.
b. Neutrophils possess one type of lysosomal granules.
c. Neutrophils have a life span of only a few days in tissues.
d. When neutrophils are released into the bloodstream, they circulate for 10 to 24 hours before migrating into the tissues.
a
The following regulatory proteins inactivate complement components that participate in both the classical and alternative pathways except
a. C4b-binding protein.
b. factor I.
c. decay-accelerating factor.
d. anaphylatoxin inactivator.
a
Regarding antigens, which of the following statements is least accurate?
a. An antigen may possess one or more antigenic determinants.
b. Only microbial pathogens function as antigens.
c. To evoke a T cell response, an antigen must be degradable.
d. Surface epitopes of the antigenic molecule usually induce protective immune responses.
b
Each cytokine is paired with a function. Which pair is mismatched?
a. CC chemokines—macrophage chemotaxis.
b. TNF—activation of endothelial cells.
c. IL-3—hematopoietic multilineage colony-stimulating factor.
d. G-CSF—supports clonal expansion of macrophages.
d
This professional antigen-presenting cell constitutively expresses MHC molecules and B7 proteins.
a. Macrophage
b. Dendritic cell
c. B cell
d. Neutrophil
b
Opsonins that bind to microbes and promote their engulfment by phagocytes include all of the following except
a. IgM.
b. IgG.
c. C3b.
d. C4b.
a
The afferent lymphatic vessel carries lymphatic fluid to this organ.
a. Spleen
b. Thymus
c. Lymph node
d. Bursa of Fabricius
c
The mononuclear phagocyte system includes all of the following except
a. mast cells.
b. mesangial cells.
c. histiocytes.
d. Kupffer cells.
a
Each of the following complement fragments acts on mast cells and basophils, causing the release of vasoactive mediators of inflammation except
a. C2a.
b. C3a.
c. C5a.
d. C4a.
a
Activation of neutrophil by this cytokine results in rearrangement of cell surface integrin, increasing its affinity for counter-receptors on vascular endothelium.
a. Interleukin-1
b. CXCL8
c. Interluekin-6
d. None of the above
b
Which pair is mismatched?
a. Elastase–a1-antitrypsin.
b. Class I MHC–B2-microglobulin.
c. Hydrogen peroxide—catalase.
d. CD35—IgG.
d
Regarding macrophages, which of the following statements is inaccurate?
a. Macrophages are long-lived cells.
b. Macrophages are major sources of cytokines and complement proteins.
c. Macrophages are polymorphonuclear leukocytes.
d. Macrophages recirculate between the bloodstream and tissues.
c
Which of the following statements is least accurate?
a. MHC genes are codominantly expressed.
b. Complement fragments function only in innate immune responses.
c. Lymphocytes migrate from the bloodstream into lymph nodes by binding to and migrating across high endothelial venules.
d. B cells are found in lymphoid follicles of the spleen and lymph nodes.
b
