Immune System (Ch 23) Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Function of the immune system

A
  • Kills infectious organisms
  • Recognizes and tolerates self cells and non harmful foreign molecules
  • immunological memory to prevent re-infection from same organisms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Parts of the immune system

A

lymphatic system, thymus, spleen, tonsils, peyers patch, and bone marroe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Function of the lymphatic system

A

Drains excess interstitial fluid to lymphatic vessels, returns to bloods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

When pressure increases in the lymphatic vessels…

A

spaces between lymph endothelial cells close to prevent fluid coming out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

function of the lymph nodes

A

recognize pathogens and some bacterial toxins that get into the lymph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Edema

A

from fluid accumulating in the interstitial space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Hypertension (causes of edema)

A

increased capillary hydrostatic pressure pushes more fluid out of capillaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Kidney Disease (causes of edema)

A

kidneys don’t properly excrete salts and water; so build-up occurs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Heart Disease (causes of edema)

A

Valve failure, obstruction and heart failure causes high venous pressure, lack of venous return

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Skeletal Pump (causes of edema)

A

long periods of standing, immobility/paralysis causes more fluid retention in veins and lymphatic system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Medications (causes of edema)

A

affect blood pressure, vascular resistance, autonomic nervous system, kidney function and osmotic balance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

plasma proteins (causes of edema)

A

Low albumin can be caused by wounds, burns, liver diseases or malnutrition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Blocked lymph vessels (causes of edema)

A

due to cancer, infection, inflammation or surgical removal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Red bone marrow

A

located in central flat bones and ends of long bones

contains hematopoietic stem cells (Pluripotent) that produce red and white blood cells and platelets (Thrombocytes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Myeloid Lineage (white blood cell)

A

innate immune system cells, RBCs and megakaryocytes (for platelets)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Lymphoid Lineage (white blood cell)

A

adaptive (aquired) immune system cells, NKs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

B cells (lymphocytes)

A

Mature in bone marrow then migrates to spleen or lymph nodes\
- responsible for “humoral response”
- phagocytic snd antigen presenting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

T cells (lymphocytes)

A

originates in bone marrow then migrate to the thymus to mature then migrates to spleen or lymph nodes
- responsible for “cell-mediated response”
- recognize microorganisms and viruses by specific antigens on their surfaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Antigens

A

part of molecules that cause an immune reaction or immune cells raise antibodies against

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Function of B and T cells

A

recognize self-antigens, our bodies remove the ones that recognize self antigens or harmless substances or our microflora

they react only to specific molecules that match their specific receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Negative selection

A

Thymocytes (immature T cells) that bind the self-proteins are destroyed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Thymus epithelial cells

A

express self-proteins found in other body regions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Immune cells

A

B and T cells, macrophages, and dendritic cells

recognize pathogens, some toxins, and dead cells carried in the lymph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Reticular fibres

A

slow and filter lymph and trap particles that may be recognized by immune cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Spleen function

A

filters blood, not lymph, but contains lymphocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

red pulp (in spleen)

A

contains macrophages, red blood cells, and platelets. breaks down old red blood cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

white pulp (in spleen)

A

contains B and T cells, macrophages and dendritic. also contains reticular fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Lymphatic nodules

A
  • similar to nodes but not surrounded by capsule
  • higher in number where pathogens may enter
  • Ex. tonsils, andenoids, Peyer’s patches (gut-assosiated lymphoid tissue (GALT))
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Microflora (microbiome)

A
  • microorganisms that normally live on us and in us (don’t cause disease)
  • works with our immune system
  • helps your immune system to tolerate non-pathogenic microorganisms
  • helps fight pathogens by establishing themselves first, limiting available binding sites and resources for pathogens
  • also alters the environment to make your body less hospitable
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

innate immune response

A
  • defense which responds in a non specific way to infection
  • doesn’t provide long term protection, but triggers cells involved in the adaptive immune response to provide long term protection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

First line of defense is preventing infection

A

skin and mucus are a physical barrier. and covered with the microflora

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Skin

A

had specialized immune cells throughout its layers to detect invasion or destroy invaders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Musus

A

found in digestive and respiratory systems (nose hairs also filter particles and induce sneezing)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Skins chemical and physical defenses

A
  • oil glands (sebaceous) make the skin surface acidic
  • saliva, sweat, snd tears contains lysozyme that attacks and digests the cell walls of many bacteria
  • skin produces RNAase which degrades RNA from microorganisms especially RNA viruses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Digestive/Respiratory systems mechanisms to prevent infection

A
  • saliva contains lysozyme
  • Hydrochloric acid and digestive enzymes protect the digestive tract.
  • Mucus traps most microorganisms in the respiratory tract, and cilia
    continually move mucus up toward the throat (swallowed or coughed
    out).
  • Resident bacteria, normal microflora in the digestive tract, help prevent infections.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Second line of defense

A

When a foreign pathogen enters the
body, the immune system detects antigens on the surface of the pathogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

cellular and chemical defenses

A
  • Cells that kill invading microbes
  • Proteins that alert other cells to the invasion
  • Proteins that kill invading microbes
  • The inflammatory response
  • The temperature response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Cytokines

A

secreted by Infected cells or those that detect the infection
- signals proteins
that alert neighbours and nearby immune cells to the infection
- positive feedback loop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Autocrine

A

act on the releasing cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

paracrine

A

act on nearby cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Chemotaxis

A

Innate immune cells move toward the infection following the increasing concentration of
cytokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Cytokines can cause immune cells to…

A

proliferate, differentiate, or trigger other functions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Neutrophils

A
  • Usually the first cells to arrive at an infection. Migrate from the bloodstream through capillaries.
    *The most numerous type of white blood cell.
    *Secrete cytokines to attract other immune cells and increase vascular permeability.
    *Engulf bacteria (phagocytosis) and attack them with enzymes and chemicals in specialized compartments.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Monocytes

A

are attracted to the infection (chemotaxis)
1. Macrophages
2. Dendritic cells
- both do clean up and antigen presenting.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Macrophages

A

specialized to engulf and remove microbes and debris from cells or dead bacteria. Clean-up crew. Help dampen the immune response once the infection is over.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Dendritic cells

A

specialized to display foreign invader’s antigens on their surface to B and T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Natural Killer Cells

A
  • kill cancerous and virus-
    infected cells by creating holes in
    their plasma membranes with
    perforin.
  • The holes allow cell-killing proteins
    from the NK cell and interstitial fluid
    to enter the cell.
  • This kills the cell directly or induces
    apoptosis.
  • Macrophages and dendritic cells
    then phagocytize the cell debris to
    remove it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

interferons

A
  • secreted by cells infected by
    viruses or bacterial toxins
  • activate NKs in infected areas
  • can activate p53 in infected cells to cause apoptosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

neighbouring uninfected cells respond by

A
  • producing proteins that inhibit viral replication
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

(true or false) some viruses prevent our cells from making interferons

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What are parly responsible for making you feel unwell when you are sick?

A

interferons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

plasma proteins made in liver

A

Inactive state until they encounter a fungi, bacteria or any antibody-covered microbe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Activated complement proteins

A
  • bind microbes and increase phagocytosis
  • stimulates mast cells to release histamine which increases vasodilation, vascular permeability, attracts phagocytes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

complement proteins

A

form a membrane attack complex (MAC); makes a pore in the foreign cell’s membrane, fluid rushes in and kills the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

membrane attack complex (MAC)

A

similar function to perforin, but it uses different proteins and acts
only on foreign cells, so it’s not the same

56
Q

Inflammation

A

triggered by physical damage, toxins, and/or infection
- often recognize tissue-specific inflammation

57
Q

Classical Signs

A
  • redness, swelling, pain, heat and reduced function.
  • Caused by vasodilation, vascular permeability and signals released by
    damaged cells and immune cells
58
Q

Acute Inflamation

A
  • short lived, localized, adaptive response
  • esolves once repair is complete or infection is cleared and can promote tissue regeneration
59
Q

Chronic Inflammation

A
  • Immune system continually attacks tissues and produces cytokines
  • collateral damage caused by immune cells damages the tissue and doesn’t resolve properly
60
Q

Mast cells and basophils release

A

histamine and prostaglandin in damaged tissue
- cause vasodilation and
increase capillary permeability

61
Q

Prostaglandins

A

activate pain sensors

62
Q

Aspirin and ibprophen

A

inhibit prostaglandin production, used to limit pain and swelling

63
Q

if blood vessels are damaged…

A

platelets convert fibrinogen in plasma into fibrin that makes blood clots. This also helps to trap pathogens and limit their spread.

64
Q

Neutrophils and macrophages

A

easily migrate from the dilated blood
vessels and kill microbes and engulf
dead cells, as well release more
chemokines and cytokines

65
Q

Pus is a mixture of…

A

bacterial, dead cells, and white blood cells

66
Q

Phagoctyes

A

clean up dead cells and microbes/debris and the tissue heals as new cells are made

67
Q

Classic/cardinal signs of inflammation

A
  1. Redness (increased blood flow)
  2. Swelling (increased vascular permeability causing edema)
  3. Pain (edema due to prostaglandins presses on pain sensors or neurons
    are injured)
  4. Heat (increased blood flow, and increased metabolism of nearby cells
    and immune cells)
68
Q

Your body temp set point is determined by the…

A

hypothalamus

69
Q

Pryogens

A

substances that trigger a fever. May be cytokines, prostaglandins or toxins made by the invading organism.

70
Q

what signals the hypothalamus to raise body temp? (fever)

A

activated immune cells releasing cytokines

71
Q

what are the fever thresholds

A

fever ≤ 39.4ºC - normal
fever > 39.5ºC - can be treated
fever > 42ºC - fatal

72
Q

Why can fevers be dangerous?

A

if temp is too high, it begins to inactivate the body’s cellular enzymes

73
Q

cells in the adaptive immune response

A

B cells, plasma cells, helper T cells, cytotoxic T cells, regulatory T cells

74
Q

antigen-presenting cells

A

monocytes differentiate into macrophages or dendritic cells (DCs), which along with B cells (before differentiation)

75
Q

Macrophages or DCs recognize pathogens by…

A

pathogen-associated molecular patterns (PAMPs), which are not found on human cells

76
Q

what have both MHC I and MCH II surface proteins?

A

antigen-presenting immune cells
- use both to present antigens to lymphocytes and activate them

77
Q

nucleated cells have what are on their surface?

A

major histocompatibility complex I (MHC I) proteins on their surface that the immune system recognizes as “self”
- everyone’s MHC signature is unique

77
Q

Activated macrophages/DCs alert other immune cells by…

A

the digested microbe fragments that are displayed on their MHC proteins

78
Q

infected cells display…

A

microbe parts on their MHC I proteins to cytotoxic T cells that will kill them.
- Normal cells display self-proteins that are ignored.

79
Q

CD4+ helper T cells

A
  • Only activated by antigens presented on MHCII by APCs
  • Do not kill pathogens or infected cells.
  • Secrete cytokines to activate B cells, cytotoxic T cells, NK cells, and macrophages.
  • Some types dampen immune response or help produce tolerance
  • CD4+ cells are targeted by HIV (other immune cells also make CD4).
80
Q

CD8+ Cytotoxic T cells

A
  • Activated by antigens presented on MHCI molecules.
  • Kill virus-infected cells, cancer cells, or transplanted cells with perforin (same as NKs)
    or by inducing apoptosis.
  • Cytotoxic T cells generally fight intracellular infections by killing the infected cells.
  • Migrate between lymph and tissues.
81
Q

what does an APC with a foreign antigen displayed do?

A

eaves the site of infection and travels the lymphatic system until it encounters a helper T cell whose receptor matches the antigen.

82
Q

APC secretes

A

nterleukin-1 (IL-1), which activates the helper T cell.

83
Q

Helper T cell secretes

A

IL-2, which acts on itself stimulating proliferation and differentiation

84
Q

4 helper T cell subtypes

A

1)TH1 cells
2)TH2 cells
3)Regulatory T cells (Tregs), also called TH17
4)Tolerant T cells (TH3) help create tolerance and do not react to antigens. High
exposure to an antigen, such as food, normal flora bacteria, and harmless
environmental molecules helps produce TH3s, especially oral exposure.

85
Q

TH1 cells

A

increase cytotoxic T cell activation for virus-infected cells.

86
Q

TH2 cells

A

increase B cell activation (antibodies) for a bacterial infection.

87
Q

Regulatory T cells (Tregs) (TH17)

A

slow down the immune response at
the end of infection or prevent reactions against self-antigens.

88
Q

Tolerant T cells (TH3)

A

help create tolerance and do not react to antigens. High exposure to an antigen, such as food, normal flora bacteria, and harmless
environmental molecules helps produce TH3s, especially oral exposure.

89
Q

Memory Cells

A

fight the same infection in the future

90
Q

antibodies have how many binding sites

A

2

91
Q

functions of antibodies

A
  • Cause agglutination (clumping) - microbes can’t function properly in clumps.
  • Opsonized pathogens are more easily phagocytized by macs, DCs, and neutrophils.
  • antibody binding a virus-infected cell targets them for killing by NKs
  • Antibody-bound pathogens activate complement and can be killed by the membrane attack complex
92
Q

secondary immune response

A

adaptive immune response to a previously encountered
antigen

93
Q

Naturally acquired active immunity

A

Contracting an active infection that produces memory cells

94
Q

Naturally acquired passive immunity

A

A mother transfers antibodies to the baby through breast feeding.
Antibodies are against an infection the mother had previously
encountered

95
Q

Artificially acquired active immunity

A

Vaccination producing memory cells without causing disease

96
Q

Artificially acquired passive immunity

A

Transferring antibodies to a person by injection. Temporary immunity to
the specific antigen.

97
Q

Vaccination

A

introducing a dead or inactivated pathogen, or protein fragments into the body, that stimulates the adaptive immune response

98
Q

Live Attenuated Vaccines

A

Prepared from attenuated (weakened) strains that are almost or completely devoid of pathogenicity, or a closely related virus, but still induce a protective immune response.

99
Q

Killed Vaccines

A
  • The most common type of traditional vaccine.
  • Virus grown in a lab on cultured cells and harvested
100
Q

Toxoid Vaccines

A
  • Toxin-producing microbes grown in a lab and the toxin harvested and
    purified.
  • Chemically-inactivated toxic compound is used as vaccine.
  • Vaccine targets the toxin rather than the microorganism
101
Q

Subunit Vaccines

A

Recombinant DNA technology can express immunogenic pathogen proteins in other organisms
- These proteins can then be used to make the vaccine with no worry of infection from the whole pathogen

102
Q

Adenovirus Vaccines

A
  • An immunogenic protein gene from a different virus is inserted into replication-deficient adenovirus
    genome.
  • Modified adenovirus is grown in the lab using special cells to make it replicate.
103
Q

mRNA Vaccines

A
  • use mRNA coding for the COVID-19 spike protein.
  • mRNA is engulfed in lipid nanoparticles. After injection, our
    cells take up the mRNA-nanoparticles by phagocytosis
104
Q

Autoimmune disease

A

the immune system attacks its own body’s cells as if they were foreign. May attack a specific cell type or a tissue.

105
Q

what happens to B and T cells for those who have autoimmune disease?

A

the cell receptors bind to self-
proteins as though it were a foreign antigen.

106
Q

when gender is affected by autoimmune disease more?

A

Female (two-thirds of cases).

107
Q

Hygiene hypothesis

A

lack of infections and/or lack of exposure to commensal microbes contributes to an increase in autoimmune and allergic diseases.

108
Q

what population has an increased risk of asthma and allergies?

A

Children who require antibiotics early in life

109
Q

Molecular mimicry (Autoimmune disease)

A

The immune system will sometimes cross-react with very similar antigens. It’s possible that the immune system
will cross-react with a self-tissue after fighting some infections

110
Q

Improper lymphocyte negative selection (Autoimmune disease)

A

If negative selection for self-tolerance fails, some self-reactive cells will move to the secondary lymphatic tissues and can react with self-proteins

111
Q

Genetic factors (Autoimmune disease)

A

ome variations of certain MHC genes affect antigen presentation. Other genes involved in immunity could also play a role,

112
Q

Gender (Autoimmune disease)

A

More females tend to have autoimmune diseases. May be due to hormonal differences or differences in how the immune system works in males vs females. No one single factor has been identified

113
Q

Latitude/ Vit D (Autoimmune disease)

A
  • Regions with more UV light
    exposure have lower incidence of
    some autoimmune diseases
    compared to northern or southern
    regions.
  • Vitamin D is a possible factor. It
    plays an important role in immune
    regulation, but supplementation
    does not treat autoimmune
    disease
114
Q

What are allergies?

A

immune system reacting to harmless foreign antigens as though
they were pathogens

115
Q

Allergies are what kind of reaction?

A

hypersensitive

116
Q

Allergies cause

A

causes vasodilation,
bronchoconstriction, mucus
production, itching, sneezing, and
watery eyes

117
Q

Anaphylaxis

A

severe allergic reaction

118
Q

what is needed for someone thats having anaphylactic shock?

A

require injection of epinephrine (e.g. EpiPen) to dilate bronchioles, reduce swelling and increase blood pressure

119
Q

An injection of epinephrine only lasts

A

20 mins
- gives you time to get help/ambulance.

120
Q

Allergy treatment involves

A

antihistamines and/or corticosteroids

121
Q

severity of an allergic reaction depends on…

A

how the immune system was sensitized, the type of allergen,
and its mode of entry into the body.

122
Q

multiple sclerosis affects…

A

myelin on axons in CNS

123
Q

Type 1 diabetes affects…

A

beta islets cells on pancreas

124
Q

celiac disease affects…

A

small intestine microvilli in cross-reaction with gluten

125
Q

Addison’s disease affects…

A

adrenal cortex

126
Q

aplastic anemia affects…

A

bone marrow

127
Q

crohns disease affects…

A

GI tract

128
Q

Ulcerative Colitis affects…

A

Large intestine

129
Q

Graves disease affects…

A

thyroid gland (hyperthyroidism)

130
Q

Hashimotos disease affects…

A

Thyroid gland (hypothyroidism)

131
Q

Lupus affects…

A

many tissues

132
Q

myasthenia gravis affects…

A

skeletal muscle

133
Q

rheumatoid arthritis affects…

A

joints

134
Q

Psoriasis affects…

A

Skin