Immunology Class Notes

1. What are the two types of white blood cells? granulocytes agranulocytes 2. What produces blood cells? bone marrow 3. What are good signs of indicating an active immune fever and inflamresponse? mation 4. Why is fever a sign of an active immune response? body increases its temperature so that microbes are not at their optimum temperature and cannot grow as quickly 5. What is a pathogen? an organism that causes disease to its host 6. What is an antigen/immunogen? the protein or polysaccharide found on the surface of a pathogen that induces a specific immune response 7. What do antigens do? they initiate antibody production 8. What do eosinophils do? participate in damaging parasitic invaders like parasitic worms 9. What do basophils do? contain secretory vesicles containing histamine and are released during in1 / 17 flammation and infection 10. What do neutrophils do? they attract foreign antigens and engulf and destroy them by phagocytosis they also create NETs 11. What do NETs do? allow neutrophils to kill extracellular pathogens while minimising damage to the host cells 12. What are monocytes and what do they do? immature cells for the first 24 hours then become macrophages (in tissues) which engulf bacteria, dead cells, and debris 13. What are the two types of lymphocyte? B T 14. What is the acronym for the different types of white Never (60-70%) blood cells? Let (20-30%) Monkeys (2-6%) Eat (1-4%) Bananas (0-1%) 15. What are the main types of inflammatory mediators? histamine prostaglandins leukotrienes bradykinins 2 / 17 cytokines interferons 16. What do inflammatory mediators do? increase permeability of blood vessels 17. What are cytokines? a group of low molecular weight regulatory proteins secreted in response to stimuli 18. What are cytokines that are secreted by lymphocytes lymphokines called? 19. What are cytokines secreted by monocytes or macrophages called? monokines 20. What are many cytokines referred to as? interleukins 21. How are blood cells formed? bone marrow produces stem cells which differentiate and turn into red blood cells the body sends signals to the bone marrow during infection to produce more red blood cells 22. What are the two types of immunity? innate/non-specific acquired/specific 23. What is acquired immunity divide into? humoral (B cells) cell mediated (T cells) 3 / 17 24. What do B cells turn into? B memory cells or plasma cells 25. What do plasma cells produce? immunoglobulins/antibodies 26. What are the types of T cell? T helper T suppressor T killer T memory 27. What is a target for the innate immune response? anything that is identified as foreign 28. What is the innate immune response activated by? the presence of antigens and some of their properties 29. What does the innate response include? - physical barriers - defence mechanisms - general immune response - inflammatory response 30. What are some physical barriers? skin guts eyelashes 31. What are some defence mechanisms? stomach acid bile bacteria in gut and tears 32. What does the inflammatory response do? actively brings immune cells to the site of an infection by oedema 4 / 17 33. What are the 3 types of antigen presenting cells? macrophages dendritic cells B cells 34. What type of cell recognises the antigen on invading mast cells bacteria? 35. What is chemotaxis? movement of an organism in response to a chemical stimulus 36. What are the signs and symptoms of the inflamma- inflammation tory response? elevated temperature redness pain fever 37. What do mast cells originate from? stem cells in the bone marrow 38. What do mast cells enter the blood as? immature cells 39. Where do immature mast cells migrate to? migrate to the tissues, where they mature into recognisable mast cells 40. What does each mature mast cell contain? hundreds of granules that contain protein and chemical mediators 41. How do mast cells protect the body from foreign invaders? detect bacteria, viruses, parasites, venom, and physical harm via their cell surface re- 5 / 17 ceptors and release histamine, leukotrienes, and prostaglandins 42. What is Factor XII also known as? Hageman factor 43. What does the process of activating mast cells begin Factor XII is with? converted into prekallikrein, which is converted into kallikrein 44. What does kallikrein do? gets out into the tissue space and converts kininogen into bradykinins 45. Where is kininogen found? can be circulating in the bloodstream naturally and leak into the tissue space due to hydrostatic pressure and leaky blood vessels 46. Where is phospholipase A2 found? on the endothelial cells 47. What does phospholipase A2 break down? breaks down the phospholipids which have been damaged by bacterial endotoxin into arachidonic acid 48. What happens to arachidonic acid? - lipoxygenase cleaves arachidonic acid into 6 / 17 leukotrienes - COX 1/2 cleaves arachidonic acid into prostaglandins 49. What do leukotrienes, prostaglandins, histamine, and bradykinins do? work on the receptors located on the endothelial cells 50. What does inflammatory mediators working on en- cause endothelial dothelial cell receptors cause? cells to contract and the spaces between them to get larger causes preformed bodies in the endothelial cells to migrate to the cell membrane surface 51. What does contraction of endothelial cells cause? causes plasma to leak out and accumulate in the interstitial space (oedema/sweeling) this is an increase in vascular permeability 52. What causes pain when bacteria attack? nociceptors are compressed by the plasma fluid which leaks into interstitial space bradykinins also stimulate the nociceptors 53. What causes redness and heat when bacteria attacks? inflammatory mediators cause vasodi- 7 / 17 lation which causes redness and heat 54. What does preformed bodies migrating to the cell membrane surface of endothelial cells stimulate? stimulates p-selectins to be displayed on the surface of the endothelial cells in the blood 55. Where are neutrophils and monocytes found? circling in the bloodstream 56. What do circulating neutrophils and monocytes do? sugar molecules on their surface interact with p-selectins on endothelial cell surface, causing them to roll along the surface 57. What is margination? when neutrophils and monocytes roll along the cell membrane, whilst interacting with p-selectins 58. What is diapedesis? monocytes and neutrophils squeeze through the gaps in the endothelial cells 59. What assists diapedesis? P CAMS assist diapedesis by hooking onto the monocytes/neutrophils and pulling 8 / 17 them through the endothelial cell gaps 60. What are monocytes that have moved out of the blood and into interstitial space called? macrophages 61. What causes positive chemotaxis of neutrophils/macrophages towards bacteria? bacteria endotoxins signal receptors on neutrophils/macrophages which cause them to migrate to where the bacteria is 62. What do neutrophils and macrophages secrete whilst fighting bacteria? IL1 IL8 TNF-alpha 63. What do IL1 and TNF-alpha do? activate endothelial cells to produce e-selectins 64. What does IL8 do? causes the production of I CAMS and V CAMS on the gaps in between endothelial cells binds to integrin on neutrophils/monocytes in the blood 65. What does the binding of IL8 to integrin on neutrophils and monocytes cause? causes them to strongly bond to the I CAMS and V CAMS which hook onto neutrophils and mono- 9 / 17 cytes and ensures they pass into the interstitial space (similarly to P CAMS) 66. When does the cellular response occur? once the macrophages and neutrophils have entered the blood and go to attack the bacteria 67. What does the cellular response involve? phagocytic cells, such as macrophages and neutrophils, to ingest and kill invading pathogens 68. Describe phagocytosis. - pseudopods engulf the bacteria into an internal phagosome - the phagosome then fuses with a lysosome to form a phagolysosome - lysosomes contain lysozymes which destroy the internalised material - the phagolysosome lowers the pH of its internal environment which kills the pathogen 10 / 17 inside, leaving behind just antigens 69. How do neutrophils kill the antigens left inside them? they undergo exocytosis of the antigens, which throws the antigens into the lymphatic system to be disposed of by lymphocytes 70. How does a neutrophil kill the bacteria inside it if it it undergoes NETs is unable to break it down fully? and then oxidative burst 71. What do NETs involve? the neutrophils release their DNA and antimicrobial granular proteins (these together form a NET) into the interstitial space and use histones to bind and tag the foreign antigens 72. Why do neutrophils use NETs to tag foreign antigens? so that enzymes or other WBCs can destroy the foreign antigen 73. What is oxidative burst? where neutrophils absorb oxygen which forms a free radical and causes it to corrode from the inside - this kills the neutrophil but 11 / 17 also the bacteria inside 74. How do macrophages kill the antigens left inside them? MHC-2 protein binds to the antigens in the phagolysosome and presents them on the surface of the macrophage the macrophage is now an APC 75. What are the two types of adaptive immunity? humoral (B cells) cell-mediated (T cells) 76. What happens to the free antigens that have under- they bind onto gone endocytosis from neutrophils? naive B cell receptors and activate the B cells 77. What does an activated B cell do once bound to the the cell memantigen? brane of the activated B cell makes a pseudopod that pulls the receptor and antigen inside into a phagosome 78. What does the activated B cell do once the receptor it produces an and antigen are inside its phagosome? MHC-II molecule which binds to the antigen and presents it on the cell surface it is now an APC 79. What are the types of cell that produce MHC-II? 12 / 17 antigen presenting cells such as macrophages, B cells, and dendritic cells 80. What do the MHC-II and foreign antigen on the sur- they bind to clusface of a macrophage bind to? ter differentiation proteins on naive T-helper cells 81. What does the binding of cluster differentiation pro- causes the producteins on naive T-helper cells to the foreign antigen tion of IL4 and IL5 and MHC-II on macrophages cause? 82. What does IL4 do? causes activated B cells to start proliferating 83. What does IL5 do? causes proliferating B cells to differentiate into plasma cells and memory B cells 84. What do plasma cells do? produce antibodies specific to the foreign antigen 85. What do antibodies do? inactivate or destroy foreign substances by neutralisation, precipitation, lysis of pathogen, opsonisation, and agglutination 86. What is neutralisation? where antibodies attach to all of the 13 / 17 antigens on a foreign body so that it is blocked from entering cells 87. What is precipitation? where soluble antibodies attach to soluble antigens of the foreign body and form an insoluble precipitate 88. What is lysis of pathogens? where antibodies attach to antigens on foreign bodies surface and a complement system of proteins attaches to the antibody an MAC then breaks off this complex and binds to the bacterial cell membrane, allowing open movement of fluids in and out of the cell 89. What is opsonisation? where a complement system attaches to the antibody that is attached to the antigen of the foreign body and acts as an opsonin this makes the foreign body more suscepti14 / 17 ble to phagocytosis by attracting macrophages 90. What is agglutination? where antibodies clump together antigens 91. What is another name for antibodies? immunoglobulins 92. Describe the basic structure of antbodies. Y-shaped monomer 2 heavy chains (polypeptides) 2 light chains (polypeptides) 93. Where are IgA immunoglobulins found? in mucus, saliva, tears, and breast milk 94. What do IgA do? protects against pathogens 95. What is IgD and what does it do? part of the B cell receptor activates basophils and mast cells 96. What does IgE do? protects against parasitic worms responsible for allergic reactions 97. What secretes IgG? secreted by plasma cells in the blood 98. What does IgG do? 15 / 17 able to cross the placenta into the foetus 99. Where is IgM found? may be attached to the surface of a B cell or secreted into the blood 100. What is IgM responsible for? early stages of immunity 101. What acronym is used for remembering the types of GAMED antibodies? 102. What are the three types of T helper cell? cytotoxic helper memory 103. What do cytotoxic T cells do? destroy antigens 104. What do helper T cells do? activate other immune cells 105. What do memory T cells do? remember the reaction for the next encounter 106. What does the lymphatic system consist of? lymph lymph vessels tonsils spleen thymus 107. What does the lymphatic system do? removes unwanted toxins, waste, and excess water from the body 108. 16 / 17 What route does lymph take around the lymphatic system? 17 / 17 lymph vessels receive lymph from the lymph capillaries and circulate it to the lymph nodes