Topic 2: Fundamentals of the Immune System Flashcards Preview

Foundations of Pathophysiology > Topic 2: Fundamentals of the Immune System > Flashcards

Flashcards in Topic 2: Fundamentals of the Immune System Deck (52):
1

Innate and adaptive: physical barriers

Innate: skin, mucous, cilia, hair, flushing mechanisms
Adaptive: nil

2

Innate and adaptive: physiological barriers

Innate: pH, temp
Adaptive: nil

3

Innate and adaptive: diversity and specificity

Innate: non-specified
Adaptive: highly specific, customised responses

4

Innate and adaptive: typical speed on onset

Innate: quick
Adaptive: slow at first exposure, but quicker subsequent exposures

5

Innate and adaptive: ability to adapt

Innate: no
Adaptive: yes

6

Innate and adaptive: immunological memory

Innate: no
Adaptive: yes

7

Innate and adaptive: key immune cells involved

Innate: mast, dendritic, microphages, macrophages, natural killer
Adaptive: B-cells --> antibodies, T-cells:helper, killer. memory, suppressor

8

Innate and adaptive: weapons used

Innate: enzymes, acid, interferons, cytokines, complement
Adaptive: antibodies and killer T-cells

9

Innate and adaptive: soluble (humeral) factors/molecules

Innate: cytokines, complement, interferons
Adaptive: antibodies

10

What are some functions of the immune system?

maintain cellular, tissue, system and whole body homeostasis

11

What is homeostasis?

maintenance of optimal body/system/organ/cell function

12

What aspects are regulated through homeostasis at a cellular and tissue level?

Cellular: cell volume, osmolarity, electrolyte concentration, intracellular pH, membrane potential, concentrations of substances (PRRs)
Tissue: cell number and composition, tissue architecture, concentration of substances, pH, temperature, osmolarity (PRRs)

13

What must a pathogen do to cause disease?

1. gain access to body
2. attach to/enter host cells
3. reproduce while avoiding the immune system

14

What is the primary system of the immune system and what does it do?

Lymphatic system
-housing system for immune cells
-transport

15

What are the organs of the immune system?

lymphatic tissues

16

What are the primary lymphatic tissues?

Bone marrow: produces all immune cells
Thymus: matures T-cells

17

What are the secondary lymphatic tissues?

Lymphatic vessels: passively drains lymph from tissue
Lymph nodes: monitor lymph for infection, house lymphocytes
Mucosa: traps potential infectants, mast cells
Spleen: house mature T- and B cells, filters RBC

18

What are the different cells of the immune system?

Erythroid: RBC, platelets
Myeloid: microphage (neutrophil, eosinophil, basophil), monocytes --> macrophages, mast cells, dendritic cells
Lymphoid: large lymphocytes (natural killer), small lymphocytes (B-cells, T-cells)

19

What does myeloid lineage include?

microphages (neutrophil, eosinophil, basophil), monocytes --> macrophages, mast cells, dendritic cells

20

What are macrophages?

migrate to vascularised tissue and break down cell walls with enzymes

21

What are mast cells?

found in areas with high amounts of blood, prominent near internal/external barriers, present in tissue trauma

22

What are dendritic cells?

tissue-resident, introduces pathogens to immune system

23

What are the cells of adaptive immunity?

T-cells, (helper, cytotoxic, suppressor), B-cells (plasma cells), dendritic cells

24

What are the large lymphocytes?

natural killer cells - kill pathogens

25

What are the small lymphocytes?

B-cells, T-cells

26

B-cells

B cells: produced + mature in bone marrow, plasma --> antibodies, memory

27

Helper-T cells

secrete cytokines, amplify antibody production

28

Cytotoxic T-cells

kill cells, enzymes, live in thymus

29

Suppressor T-cells

dampen/suppress immune response

30

Memory T-cells

recognise original invading antigen, immunological memory

31

What are the molecules of the innate and adaptive immune systems?

Innate: cytokines (chemokines, interleukins, interferons), complement
Adaptive: antibodies

32

Cytokines

-used for communication between immune cells
-cell activation and deactivation, up- or down- regulate synthesis

33

What are the types of cytokines?

Chemokines: guide immune cells to infection site, 'chemical trail'
Interleukins: communication between leucocytes
Interferson: produced and released by host cells in response to presence of pathogens

34

What is the complement system?

proteins circulating within the blood stream and break down cell walls, facilitates inflammation

35

What are the key defence mechanisms?

Innate: first line of defense, cellular
Adaptive: second line of defense, highly specific

36

What are the physical barriers of the first line of defence?

skin, mucous membranes, hair, cilia

37

What are the mechanical barriers of the first line of defence?

vomiting, coughing, sneezing, urinating, defecating

38

What are the physiological barriers of the first line of defence?

pH, temperature

39

What are the chemical barriers of the first line of defence?

nitric oxide, catabolic enzymes, cytotoxic proteins, acid, lysosomal enzymes (saliva, ear wax, sebum, sweat glands), physical properties (ie sticky wax, mucous)

40

What is the innate cellular immune response?

non specific, no immunological memory, deals with pathogens the same way every time

41

What are the cells of innate cellular immunity?

macrophages, mast cells, natural killer, dendritic

42

Eosinophils

degrade pathogens with cytotoxic substances, explosive

43

Neutrophils

principal phagocytic cell, collateral damage, suicide by apoptosis

44

Basophils

similar to eosinophils and mast cells, explosive

45

What is the adaptive immune system?

highly specific, immunological memory

46

What is immunological memory?

faster and stronger subsequent responses - antibodies produced in secondary response = greater affinity for antigen

47

How is the immune response triggered? (pathogens)

1. pathogens invade host
2. pathogens release PAMPs
3. PAMPs recognised by PRRs in innate system
4, PAMPs captured by innate immune cells and presented to other immune cells

48

What are PAMPs?

pathogen-associated molecular patterns, induce inflammation, identify pathogens to innate immune cells

49

What are PRRs?

pattern-recognition receptors, surface receptors on resident innate immune and parenchymal cells that response to PAMPs, trigger response of other immune cells

50

What are inducers of inflammation?

PAMPs, DAMPs, pH, hyperoxia, obesity/overweight, lifestyle factors

51

What are some examples of when immunity goes wrong?

allergies, arthritis, anaphylactic shock, cancer, septic shock, transplant rejection, HIV

52

How is the immune response triggered? (no pathogens)

1. tissue damage
2. DAMPs released by distressed/damaged/dying cells
3. DAMPs recognised by PRRs in innate system
4. DAMPs captured by innate cells