Microbiology Chapter 14

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Microbiology Chapter 14
2014-03-25 15:07:44
Microbiology Chapter 14
Microbiology Chapter 14
Microbiology Chapter 14
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  1. What is innate Immunity?
    • Routine, non specific, protection
    • involves patter recognition of specific molecules
  2. What is the first line of defense in the innate immunity?
    Skin and mucous membranes
  3. What does innate immunity involve?
    • Anatomical and physical barriers
    • cells of the immune system
    • sensor systems
    • phagocytosis
    • inflammation
    • fever
  4. What are the levels of skin?
    • epidermis
    • dermi
  5. What are the movements of the mucous membrane?
    • peristalsis of intestines
    • mucociliary escalator of he respiratory tract
  6. What is keratin?
    protein that repels water and maintains dry environement found on the epidermis
  7. What are the antimicrobial substances?
    • Salt
    • lysozyme
    • peroxidase enzyme
    • lactoferrin and transferrin
    • Defensins
  8. Where is the antimicrobial substance salt found?
  9. Where is the antimicrobial substance lysozyme found?
    • Tears, saliva, mucous
    • breaks down peptidoglycan
  10. Where is the antimicrobial substance Peroxidase Enzyme found?
    • saliva
    • breaks down H2O2 to form ROS to kill bacteria
  11. Where is the antimicrobial substance lactoferrin and transferrin found?
    • lactoferrin: saliva, mucous
    • transferrin: blood and tissue fluids
    • binds to iron so pathogens cannot
  12. Where is the antimicrobial substance defensins
    • produce by epithelial cells
    • insert into bacterial membranes to form pores
  13. How does normal microbiota help the immune system?
    • compete with pathogens 
    • consume available nutrients
    • production of toxic compounds
  14. What are examples of normal microbiota producing toxic compounds?
    • E.coli may synthesize colicins in intestinal tract
    • lactobacillus in vagina produce low pH
  15. What are the cells of the immune system?
    blood cells
  16. What is the origin of all blood cells?
    hematopoietic stem cells
  17. What are the 3 categories of blood cells?
    • Erythrocytes
    • platelets
    • leukocytes
  18. What are the 4 types of leukocytes?
    • granulocytes
    • mononuclear phagocytes
    • dendritic cells
    • lymphocytes
  19. Why are granulocytes name as such?
    They contain cytoplasmic granules
  20. What are the three granulocytes?
    • neutrophils
    • basophils
    • eosinophils
  21. What are neutrophils involved in?
    engulf and destroy bacteria and other material via phagocytosis
  22. What are basophils involved in?
    filled with mediators that produce allergic reactions
  23. What are eosinophils involved with?
    parasitic worms
  24. What do mononuclear phagocytes comprise?
    mononuclear phagocyte system (MPS)
  25. What are the 2 cells that come from mononuclear phagocytes?
    • Macrophages 
    • Dendritic cells
  26. How are macrophages named?
    • For their location
    • ex. kupffer cells-liver
    • microglial cells- brain
    • alveolar- lungs
  27. What is the function of dendritic cells?
    • sentinel cells
    • They engulf cells and bring them to the adaptive immune system for inspection
  28. What are the cells that comprise lymphocytes?
    • B Cells
    • T Cells
    • NK Cells
  29. What is the difference between B, T cells and NK cells?
    • B, T cells are highly specific in recognition of an antigen
    • NK cells lack specificity
  30. What are surface receptors?
    "eyes" and "ears" of the cell
  31. What is a ligand?
    molecule that bind to a surface receptor in order to communicate what is going on in the environment to the interior of the white blood cell
  32. What are cytokines
    • Serves as "voice"
    • produced a chemical that diffuses to other cells to induce changes 
    • changes include growth, differentiation, movement, apoptosis
  33. What are the 5 different types of cytokines?
    • Chemokines
    • colony stimulation factors
    • interferons
    • interleukin
    • tumor necrosis factor
  34. What are chemokines?
    • chemotaxis of immune cells
    • movement of cells
  35. What are colony stimulating factors (CSFs)
    proliferation (multiplication) and differentiation of leukocytes
  36. What do interferons (IFNs) do?
    control viral infections and regulate inflammatory response
  37. What do Interleukins (ILs) do?
    made by leukocytes, ex. activation of B and T cells
  38. What do Tumor necrosis factor (TNF) do?
    induces inflammatory response and also apoptosis
  39. What do adhesion molecules do?
    • allow cells to adhere to other cells
    • ex. endothelial cells (blood vessel wall) adhere to phagocytic cells in blood to allow them to exit the blood stream
  40. What are the 3 types of Pattern Recognition Receptors (PRRs)
    • Toll-Like Receptors (TLRs)
    • NOD-like receptors (NLRs)
    • RIG-like receptors (RLRs)
  41. What are the three things identified by Pattern Recognition Receptors (PRRs)
    • Pathogen associated molecular pattern (PAMPs)
    • Microbe-associated molecular patterns (MAMPs)
    • Danger-associated molecular patterns (DAMPs)
  42. What are PAMPs?
    • pathogen associate molecular patterns
    • ie. peptidoglycan, lipopolysaccharides, viral RNA molecules
  43. What are MAMPS?
    • Microbe-associated Molecule patterns
    • Things associated with all microbes, not just pathogens, ie flagella
  44. What are DAMPs
    • Danger-associated molecular patterns
    • molecules that indicate host cell damage
  45. What do TLRs detect?
    PAMPs, pathogen associated molecular patterns
  46. What happens when a TLR( toll like receptor) detects a PAMP?
    a signal is transmitted to the cell's nucleus to express certain genes
  47. Where are TLRs?
    the membrane
  48. Where are NOD-like receptors?
    cytoplasm of sentinel cell
  49. What do NOD-like receptors do?
    detect PAMPs within the cell and initiate a series of events to protect the host
  50. Where are rig-like receptors?
  51. What do RIG-like receptors detect?
    Viral RNA within the cell
  52. How do RIG-like receptors respond to Viral RNA
    Produces interferons as a response to the viral infection, these then diffuse into neighboring cells to produce iAVPs
  53. What is iAVP?
    inactive Antiviral Proetins
  54. What do iAVP do?
    activated by viral dsRNA and degrade host mRNA to undergo apoptosis
  55. The complement system is called that because
    the proteins assist the immune system
  56. What are the numbers of the complement system proteins?
  57. When are complement proteins activated?
    When they are split into fragments which also causes a cascading activation
  58. What are the 3 outcomes of the complement system?
    • opsonization
    • inflammatory response
    • Lysis of foreign cells
  59. What occurs during opsonization?
    C3b binds to bacterial cells and allows phagocytes to engulf them more easily
  60. What occurs during the inflamatory response from the complement system?
    C5a attracts phagocytes to area; C3a and C5a increase permeability of blood vessels, induce mast cells to release cytokines
  61. What occurs during lysis of foreign cells from the complement system?
    membrane attack complexes (MACs) formed by proteins C5b, C6, C7, C8, C9 molecules cause cell lysis after inserting themselves into gram negative membranes
  62. What are the steps in phagocytosis?
    • Chemotaxis
    • recognition and attachment
    • engulfment
    • phagosome maturation and phagolysozome formation
    • destruction and digestion
    • exocytosis
  63. What occurs during the chemotaxis step in phagocytosis?
    Phagocytes are recruited to the site of damage by chemoattractants
  64. What occurs during the recognition and attachement phase of phagocytosis?
    • phagocytes use various receptors to bind invading microbes. 
    • ex. C3b or antibodies
  65. What occurs during the engulfment phase of phagocytosis?
    pseudopods surround the microbe and engulf it; forming a phagosome
  66. What occurs during the phagosome maturation and phagolsozome formation step of phagocytosis?
    • Phagosome fuses with lysozome
    • pH is lowered in lysozome delivers enzymes
  67. What occurs during the destruction and digestion phase of phagocytosis?
    • toxic ROS is produce
    • pH decreases
    • enzymes degrade invader
    • defensins damage membrane
    • lactoferrin binds iron
  68. What occurs during exocytosis phase of phagocytosis?
    the phagolysozome fuses with the plasma membrane and expels undigested remains or invader
  69. What are the two types of phagocytes?
    macrophages nad neutrophils
  70. What do macrophages act as?
    scavengers and sentries
  71. What are activated macrophages?
    increased macrophages via T cells
  72. What consitutates a giant cell?
    macrophage, giant cells and T cells
  73. What is a granuloma
    • a giant cell, macrophage and T cell 
    • found in tuberculosis
  74. What to neutrophils act as?
    rapid response team: move into area and elimante invaders
  75. What is the difference between a neutrophil and a macrophage?
    • Neutrophils are more powerful, but have a shorter lifespan
    • MAcrophages are not as powerful, but have a lifespan of weeks to months
  76. How do neutrophils eliminate invaders?
    • phagocytosis
    • releasing granules that kill invaders
  77. What is the cause of inflammation?
    tissue damage
  78. What are the symptoms of inflammation?
    swelling, redness, heat, pain and sometimes loss of function
  79. What is the purpose of inflammation?
    • contain site of damage
    • localize response
    • eliminate invader
    • resotre tissue function
  80. What is inflammation triggered by?
    TLRs and NLRs that detect PAMPs and DAMPs
  81. What are examples of inflammatory mediators?
    • histamine
    • bradykinin
  82. What occurs when blood vessels are damaged?
    coagulation of blood and increased blood vessel permeability
  83. What is diapedesis?
    when leukocytes phase out of the vessel into tissue
  84. What is acute inflammation?
    • short term;
    • macrophages clean up damage by ingesting dead cells and debris
  85. What is chronic inflammation?
    • when acute inflammation fails
    • macrophages and giant cells accumulate and granulomas form
  86. Whatis apoptosis?
    programmed cell death
  87. What is pyroptosis?
    programmed cell death, causes inflammation
  88. What regulates host temperature?
  89. What causes a raise in body temperature?
  90. What are endogenous pyrogens?
    made by macrophages, fever inducing
  91. What are exogenous pyrogens?
    microbial products that induce fever
  92. What occurs from increased temperature?
    increases enzyme activity and decreases microbial growth