IS 2 Flashcards
Positive selection in the thymus occurs when thymocytes express functional versions of which critical molecule?
CD28 Fc receptor MHC class I MHC class II T-cell receptor (TCR)
T-cell receptor (TCR)
Which one of the following represents the major role of negative selection in the thymus?
Expansion of nonself-reactive T cells
Maturation of professional antigen presenting cells such…
Elimination of self-reactive T cells
Expression of T-cell receptors on mature T cells
Differentiation of Th1 and Th2 CD4+ T cells
Elimination of self-reactive T cells
A blood sample from an individual with systemic lupus erythematosus was studied in a research project mapping-cell
receptor specificities. Many T cells were discovered to express receptors specific for autologous antigens. Failure of which process in the thymus leads to a large number of autoreactive T cells in the patient’s blood?
Affinity maturation Antigen processing Hematopoiesis Negative selection Receptor editing
Negative selection
T helper cells interacting with antigen-presenting dendritic cells require signals generated by the molecular interactions of the T-cell receptor with the MHC–peptide complex. Additionally, costimulation is required to amplify the initial TCR signals provided through the T cell CD28 molecule interaction with which one of the following dendritic cell molecule(s)?
CD4 CD8 CD45 CD80/86 CD152
CD80/86
Dendritic cells, macrophages, and what other cell types are considered “professional antigen-presenting cells,” capable of antigen presentation to T helper cells?
B cells Basophils Eosinophils Mast cells Neutrophils
B cells
Antigens from which one of the following microbes would be presented on MHC class I molecules by macrophages?
Ascaris lumbricoides Candida albicans Haemophilus infl uenzae Influenza virus Streptococcus pneumoniae
Influenza virus
Which cells utilize reactive oxygen and nitrogen species and lysosomal enzymes to kill pathogens?
Cytotoxic T cells Natural killer T (NKT) cells Natural killer (NK) cells Macrophages Th1 cells
Macrophages
If a person had a genetic defect affecting perforin production, which cells and immune function would be affected?
Cytotoxic T cells and natural killer cells/cell killing
Dendritic cells/antigen presentation
Eosinophils and basophils/granule production
Macrophages and neutrophils/phagocytosis
Mast cells/fusion of granules tocell membrane
Cytotoxic T cells and natural killer cells/cell killing
Which immune system cell is primarily responsible for the formation of granuloma in the lungs of tuberculosis patients?
Cytotoxic T cells Dendritic cells Eosinophils Natural killer cells Th1 cells
Th1 cells
Macrophages recognize microorganisms through the interaction of microbial substances with what type of receptors on macrophages? Antigen receptors Complement receptors Fc receptors Membrane immunoglobulin Pattern recognition receptors
Pattern recognition receptors
Thymocytes interacting with self-peptides undergo negative selection. The self-peptides in this reaction as:
Allergens Tolerogens Haptens Immunogens Antigens
Tolerogens
Neutrophils are attracted to the sites of extracellular bacterial infections by which two important chemotactic substances?
Bacterial mannose and lipopolysaccharide
Histamine and complement C3b
Interleukin-7 and interleukin-16
Complement C5a and interleukin-8 (CXCL-8)
Leukotriene B4 and granulocyte colonystimulating factor (G-CSF)
Complement C5a and interleukin-8 (CXCL-8)
Which immune system cells recognize body cells with reduced expression of MHC class I molecules?
Cytotoxic T cells Dendritic cells Macrophages Natural killer cells Neutrophils
Natural killer cells
Which one of the following leukocytes is considered a “granulocyte”?
Macrophage Neutrophil Dendritic cell Natural killer cell Natural killer T cell
Neutrophil
A 45-year-old female presents with anorexia and some abdominal pain. Fecal smears reveal the presence ofTaenia eggs, products of a parasitic tapeworm infection. Which one of the following cells would be most effective in defense against this parasite?
Platelets Erythrocytes Neutrophils Eosinophils Monocytes
Eosinophils