UNIT 4 - RESISTANCE & IMMUNITY Flashcards
(120 cards)
1
Q
Granulocytes (3)
A
- Neutrophils
- Eosinophils
- Basophils
2
Q
Agranulocytes (2)
A
- Lymphocytes
- Monocytes
3
Q
Importance of leucocyte count
A
Each leucocyte has a definite purpose and seeing changes in specific types can help diagnose a problem
4
Q
Differential count
A
Used in diagnosis of an infection/disease on basis of an increase or decrease in numbers of specific types of WBC
5
Q
Relative quantities of leucocytes in blood (5)
A
- Neutrophils (60-70%) - Lymphocytes (20-25%)
- Monocytes (3-8%)
- Eosinophils (2-4%)
- Basophils (0.5-1%)
6
Q
Lymphatic system
A
Group of organs, vessels, and tissues that protect us from infection and keeps a healthy balance of fluids throughout the body
7
Q
Plasma
A
Fluid portion of blood
8
Q
Interstitial fluid
A
Fluid between tissues and cells (bathes tissues)
9
Q
Lymph
A
Fluid in lymphatic vessels (mostly interstitial fluid) that bring back fluid from body and drain into circulatory system through two ducts in neck region
10
Q
Lymph nodes
A
Located in lymphatic vessels that contain WBC to filter and cleanse the lymph of pathogens and abnormal cells before returning to circulatory system
11
Q
Movement of lymphatic system (4)
A
- Interstitial fluid with the white blood cells enters lymphatic capillaries through small pores
- Fluid inside lymphatic capillaries (lymph) flows through lymphatic vessels throughout body
- Microbes and foreign particles present in circulating lymph encounter macrophages, dendritic cells, and lymphocytes that carry out various defensive actions within lymph nodes
- Lymphatic vessels return lymph to the blood via 2 large ducts that drain into vein near neck/shoulders
12
Q
What happens to the majority of fluid that leaves the capillaries
A
The majority of fluid that leaves the capillaries is returned to the circulatory system, but approximately 15% remain in tissues as part of interstitial fluid and blood volume in arteries is 15% more than veins
13
Q
What happens to this “lost fluid” and how is arterial volume restored
A
Restored to the circulatory system through lymphatic system
14
Q
Functions of lymphatic system (4)
A
- Drains excess interstitial fluid to restore blood volume
- Protects against invasion through immune responses
- Transports dietary lipids and some vitamins from the gastrointestinal tract to the blood
- Return tissue fluid back to circulatory system
15
Q
Drains excess interstitial fluid to restore blood volume
A
One way transport system that drains fluid from all body tissues and returns it to the blood at the left and right subclavian veins
16
Q
Protects against invasion through immune responses
A
Lymph pass through nodes that contain WBC and initiate defensive and immune responses
17
Q
Lymph
A
Fluid in lymph vessels, mostly just interstitial fluid in lymphatic vessels that bring back fluid from body and drain into circulatory system through two ducts in neck region
18
Q
Nodes
A
Oval/bean shaped swellings situated throughout lymphatic vessels to filter fluid within vessels
19
Q
2 ducts in neck region:
A
- Right lymphatic duct –> right subclavian vein
- Thoracic duct –> left subclavian vein
20
Q
Structural characteristic of the circulatory system
A
Moves as a circuit with a pump
21
Q
Structural characteristics of the lymphatic system
A
One way system and has no pump. The movement of lymph is due to pressure differences aided by muscular action (smooth/skeletal) and forced through vessels
22
Q
Spleen
A
Contains the largest amount of lymphoid tissue in body and controls the level of white blood cells, red blood cells and platelets
23
Q
Tonsils
A
Masses of lymphoid nodules in pharynx and functions in filtering and immunological role
24
Q
Thymus
A
Small grainy lymphoid organ located behind sternum for maturating of certain WBC
25
Resistance & immunity
Refers to the body's ability to protect itself from foreign substances and pathogens (avoid disease)
26
2 major lines of defense of the immune system
- Innate (inherited) non specific resistance
- Adaptive specific resistance
27
Innate (inherited) non specific resistance
First line of defense that provides protective mechanisms to all people and responds in the same way to all potential invaders
28
Types of innate (inherited) non specific resistance:
- External defenses: skin & mucous membranes, body secretions
- Internal defenses: antimicrobial proteins, phagocytosis, fever, inflammation
29
Skin and mucous membrane
Unbroken skin and mucous membranes act as mechanical barrier to bacteria and viruses
30
Mucous
Produced in respiratory tract to trap debris and germs swept out by cilia
31
Gastric juice
Acid and enzymes in the gut to kill off bacteria and virus
32
Tears
Flush the eyes to remove dirt and bacteria containing enzyme lysozyme
33
Saliva
Flushes inside of the mouth containing enzyme lysozyme and immunoglobin
34
Sweat and oil
Produced by the skin, where sweat flushes skin and deposits salt on skin surface and oil from sebaceous glands contain antimicrobial compounds
35
Antimicrobial proteins
Proteins present in plasma or produced by infected cells
36
2 principle components of antimicrobial proteins
- Interferon
- Complement
- They are both also part of adaptive specific resistance
37
Interferon
Protein produced by infected cells that bind to surrounding non-infected cells and cause them to produce substances that interfere with viral replication
38
Complement
Protein produced by the liver found in plasma that bind to bacterial cells to attract phagocytes and cause holes in bacteria walls and consequent rupturing
39
Phagocytosis
Involves various white blood cells (macrophages, neutrophils, dendritic cells) that engulf foreign materials upon contact aided by complement proteins and fevers (phagocytes function better at high temperatures)
40
Fever
An abnormally high body temperature commonly occurring during infections
41
Impact of a high temperature (4)
- Intensifies effect of interferon
- Increases phagocytic action
- Inhibits growth and multiplication of microbes
- Speeds up bodies repair and resistance mechanisms
42
Inflammation
Response by the body to tissue damage due to injury and/or infection to prevent spread of infection and prepare the area for repair and destroy toxins
43
Symptoms of inflammation (3)
- Localized pain
- Swelling (caused by WBC releasing histamine, prostaglandin, complement, etc)
- Redness/heat (caused by vasodilation and blood vessels more permeable so WBC move out quickly)
44
Process of inflammation (3)
- Blood vessels dilate bringing increased blood flow to injury
- Phagocytes migrate to the injury site and ingest microbes and other foreign substances
- Lymphatic drainage removes dissolved poisonous substances for healing
45
Antigen
Something that is able to trigger an immune response if body is foreign to it (Create a defence)
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Antibodies
Protein produced by immune system to fight against specific invaders (antigens) like bacteria or viruses
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2 characteristics of antigens:
- Immunogenicity
- Reactivity
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Immunogenicity
Ability to provoke immune response
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Reactivity
Ability of antigen to react specifically with antibodies it provoked
50
Epitope/antigen determinant
Region/site on antigen that acts as unique identifying markers on antigens that the immune system uses to recognize and respond to foreign substances
51
Adaptive specific resistance (4)
- Third line of defense that occurs in response to PARTICULAR pathogen that managed to get through all the non-specific defenses and unique to individual
- Involves activation of immune system
- Slower response as body must produce antibodies and active certain cells
- Cannot get started without aid of nonspecific phagocytosis occurring in innate immune response
52
Antigen presenting cells
Phagocytic cells that initiate the process of adaptive specific resistance (eg. Dendritic cells, macrophages, activated B cells)
53
Macrophages
Produced through differentiation of monocytes and roam throughout the body particularly concentrated in skin, lungs, mucous membranes, and around the intestine (where pathogens are most likely to enter the body)
54
Macrophages function (4)
- Phagocytose debris, foreign pathogens, dead/damaged cells
- Release antimicrobial chemicals to attract leucocytes to site of infection
- Present antigens to T cells and activate
- Initiate inflammation by releasing molecules (cytokines) that activate other cells
55
Immune response
The production of specific cell types and antibodies
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Immunity
Function of lymphocytes found mainly in lymphatic system + spleen, bone marrow, blood, gut, skin tissues
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2 categories of adaptive specific resistance
Cell mediated and antibody mediated
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2 categories of lymphocytes
B-lymphocytes (B-cells); humoral immunity and T-lymphocytes (T-cells); cellular immunity
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Humoral immunity (antibody-mediated)
Involves production of antibodies (immunoglobins) that react with an antigen on invading organism, and works against extracellular pathogens in fluids outside cells
60
Cellular immunity (cell-mediated)
Production of cytotoxic T cells that directly attack the invading organisms, and are particularly effective against intracellular pathogens, some cancer cells and foreign tissue transplants
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B cells
Develops in red bone marrow and produce antibodies found in general location but mostly in nodes and differentiates into plasma cells and memory cells
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Plasma cells
Differentiated B cells capable of secreting immunoglobulin or antibodies by leaving lymph node and enter general circulation
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When is antibody production stopped
When all foreign antigens are destroyed, the antibody production will slow and stop
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Memory B cells
Can remember the recognized antigen to improve secondary response
65
Are you forever immune if once infected
No, immunity may decrease over time if the person is not challenged by that specific antigen
66
Steps for antibodies to protect us from pathogens (5
)
1. Complement activation
2. Ab dependant cell mediated toxicity
3. Neutralization: antibody binds and blocks virus
4. Agglutination: clumping of bacteria and reduces number of growth
5. Opsonization: coats the antigen with antibodies to signal phagocyte (makes pathogen tasty)
67
T cells
Develops in red bone marrow, then migrate to Thymus and does not produce antibodies, but develops effector T helper cells and effector cytotoxic T cell
68
Immunocompetence & immunotolerance
Ability to carry out specific immune responses & distinguish "self" from "non-self"
69
Cytotoxic T cell
Direct killing of intracellular pathogens and elimination of mutated and cancerous cells
70
Activation of cytotoxic T cell
Activated when it recognizes an abnormal or infected cell/virus then kills it
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Helper T cell cells
Directs by secreting, signalling proteins and activates
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Activation of helper T cells
When macrophages eats an infected cell it presents a small amount of its antigen to signal and activate the helper T cell
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Memory T cells
Can remember the recognized antigen to improve secondary response
74
Cytokines
Activates B cells, T cells, macrophages
75
Interleukins
Stimulates B & T cell reproduction
76
Importance of cellular response (4)
- T cells recognize and respond to processed fragments of antigen displayed on surface of APC
- Targets cells infected with viruses, bacteria, or intracellular parasites
- Targets abnormal/cancerous cells
- Targets cells of infused or transplanted foreign tissue
77
Ways antibodies destroy/inactivate foreign substance in body (6)
- Direct opsonization
- Indirect opsonization
- Neutralizes
- Complement system
- Immobilizing bacteria
- Activation of anaphylactic system
78
Complement system
Antibodies activate complement system consisting of blood proteins that help immune system
79
Immobilizing bacteria
Binds flagella making it harder for bacteria to spread
80
Activation of anaphylactic system
Allergic reaction involving IgE which helps to localize the invading agents by swelling tissue and attracting immune cells
81
5 types of antibodies (6)
- IgG: Most common antibody in plasma
- IgA: Most common antibody in mucous membrane
- IgD: Has immunological functions
- IgE: Killing of worm parasites and allergic reactions
- IgM: Largest antibody and is the first to appear in response to initial exposure to antigen
- Ig is short for immunoglobulin
82
Immunization
Process by which resistance to disease can be induced or augmented
83
Induced
Stimulating immunity of body to a specific disease that has not been encountered yet to prevent infection achieved through vaccinations (active immunization)
84
Augmented
Supplementing/boosting bodies own response to particular disease achieved through injection of specific antibodies (passive immunization)
85
Types of active immunizations (3)
- Injection of dead organisms (eg, typhoid fever, diphtheria)
- Injection of moified toxins (eg, tetanus, botulism)
- Injection of live weakened organisms (Eg, measles, chicken pox)
86
mRNA
Teach our cells how to make a protein that triggers an immune response inside our bodies
87
Immunological tolerance
Ability for immune system to distinguish between self and non-self to prevents immune cells from attacking our own body's proteins and tissues, generated during maturation of lymphocytes when B and T cells with reactivity to body's own tissues die or inactivated
88
Autoimmune disease
Failure of the immunological tolerance
89
Autoantibodies
Antibodies that react with self-antigens (respond to body's own proteins)
90
Autoimmune disease general facts (3)
- Frequency 5% in North America, more common in females
- Can be caused by production of autoantibodies (eg. Myasthenia gravis; targets neuromuscular junctions causing muscle weakness)
- Activation of cytotoxic T cells (Type I diabetes, multiple sclerosis, systematic lupus erythematosus)
91
Rheumatoid arthritis
Immune system attacks healthy cells in body by mistake and cause inflammation
92
Addisons disease
Immune system attacks adrenal glands and severely damage adrenal cortex which impacts production of steroid hormones cortisol and aldosterone
93
AIDS (4)
- Prevalence of 38.4 million worldwide; 63,000 in Canada
- HIV infects and kills helper T cells
- After prolonged incubation period, opportunistic infections occur and cancer
- Treatment is antiretroviral therapy
94
Opportunistic infections
Infections that occur more frequently and more severe in people with weakened immune systems (eg. Pneumonia)
95
4 major types of blood in humans
A, B, AB, O
96
How is blood type determined (3)
- By the presence of specific proteins and attached carbohydrates
- One group is attached to the RBC membrane: Antigen
- Other group is found in the plasma: Antibodies/agglutinins
- Antigens determine group group
97
Type A blood
A antigen, anti B antibody
98
Type B blood
B antigen, anti A antibody
99
Type AB blood
A & B antigen, no antibody
100
Type O blood
No antigen, Anti A & B antibody
101
Agglutination and hemolysis
Blood clotting that occurs if the RBC is placed into plasma that contains the opposite antibody and the destruction of RBC
102
Blood transfusions:
For any recipient to receive blood from a donor, there should be a direct match (A-->A, B-->B. O-->O. AB-->AB; preferable), or recipients plasma cannot contain the antibody that will cause the donor cells to agglutinate; in emergencies
103
Recipient blood group A
Possible donor is A or O
104
Recipient blood group B
Possible donor is B or O
105
Recipient blood group AB
Possible donor is AB, A, B, or O
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Recipient blood group O
Possible donor is O
107
Universal recipient
Blood AB+
108
Universal donor
Blood O
109
Rhesus (Rh) antigen
Individuals with this antigen are Rh+, individuals without this antigen are Rh-. Most people are Rh+ and the Rh factor is important for pregnancy
110
Do people have Rh antibodies
No but if someone who is Rh- is exposed to Rh antigen, then the body will detect it as foreign and will make antibodies against it
111
Rh factor in pregnancy (3)
- First pregnancy: Father is Rh+, mother is Rh-, baby is Rh+ (born fine). Prior to and during birth, some of the baby's RBC leak into mothers circulation
- Between pregnancy: Mother produces antibodies against Rh antigen from the baby
- Second pregnancy: If baby is Rh+, antibodies from the mother cross the placenta and cause agglutination and destroy the RBC of baby = hemolytic disease of new born. However, if baby is Rh- (like mother) there is no problem
112
Prevention of haemolytic disease of new born
Giving the mother immunoglobulin treatment after 1st birth to prevent the antibody production
113
A+
Agglutination with Anti A and Anti Rh
114
A-
Agglutination with Anti A
115
B+
Agglutination with Anti B and Anti Rh
116
B-
Agglutination with Anti B
117
AB+
Agglutination with Anti A, Anti B and Anti Rh
118
AB-
Agglutination with Anti A and Anti B
119
O+
Agglutination with Anti Rh
120
O-
No agglutination
