Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Week 2 - General Pathology > Immunology 1 - Cells of the Immune System > Flashcards

Immunology 1 - Cells of the Immune System Flashcards

1
Q

What are the soluble and cellular factors involved in innate immunity? [3]

A
  1. soluble factors:
    • antibacterial factors
    • complement system
  2. cellular factors:
    • scavenger phagocytes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Antibacterial factors involved in innate immunity:

  1. what are they? [2]
  2. what type of molecule are each of them? [2]
  3. where they can be found? [2]
  4. their functions [3]
A
  1. lysozyme
    • ​​enzyme
    • present at mucosal surfaces in respiratory and GI tract
    • active in breaking donw the gram positive cell wall
  2. lactoferrin
    • ​​protein
    • found at mucosal surfaces in respiratory and GI tract
    • chelates iron → reduces soluble iron in GI/resp tract and therefore inhibiting the growth of bacteria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the complement pathways [7]

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

Define opsonisation [1]

A

attracting immune cells and antibodies to the site

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

What is the function of the following protein factors in complement:

  1. C5? [1]
  2. C3a? [1]
  3. C3b? [1]
A
  1. C5 causes formation of the membrane attack complex which disrupts cell membranes causing cell lysis and death
  2. C3a causes recruitment of inflammatory cells
  3. C3b causes opsonisation and phagocytosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Macrophages

  1. difference between a monocyte and macrophage? [1]
  2. macrophages in the liver are called? [1]
  3. macrophages in the CNS are called? [1]
  4. functions of macrophages? [3]
A
  1. monocyte (blood) = macrophage (tissue)
  2. Kupffer cells
  3. microglia
  4. functions:
    • phagocytosis
      • specialises in destruction of pathogens
    • antigen presentation
      • processes engulfed particles, travels to draining lymph nodes and presents to T cells in MHC II
    • cytokine production
      • M1, TNF-α etc. - inflammatory
      • M2, IL-10 etc. - regulatory
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 3 functions of pattern recognition receptors? [3]

A
  1. recognise molcules found commonly in microorganisms
  2. able to recognise extracellular and intracellular threats
  3. respond to bacteria, fungi and yeasts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Neutrophils

  1. functions of neutrophils? [3]
  2. neutrophils die locally forming what? [1]
A
  1. functions:
    • chemotaxis
      • migrate towards bacterial products, chemokines and danger signals
    • phagocytosis
      • ingest and destroy pathogens using proteases, reactive oxygen species, lysoszyme etc.
    • degranulation
      • releasing toxic granules extracellularly
  2. they die locally producing pus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Eosinophils

  1. functions? [3]
  2. they classically respond to which type of microorganism? [1]
A
  1. functions:
    • chemotaxis
      • migrate in response to chemokines
    • degranulation
      • releasing toxic substances onto the surface of parasites
    • cytokine production
      • drives inflammation
      • production of IL-1, IL-2, IL-4, IL-8, TNF-α
  2. classically respond to parasites
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Basophils/Mast cells

  1. difference between basophils and mast cells? [1]
  2. where are mast cells usually found guarding? [1]
  3. play an important role in what condition? [1]
  4. functions of basophils/mast cells? [2]
A
  1. basophils (blood) = mast cells (tissues)
  2. guarding mucosal sites
  3. play an important role in allergy
  4. functions:
    • degranulation
      • ​rapidly releasing pre-formed granules containing cytokines and mediators (e.g. histamine)
    • cytokine release
      • store many pre-formed cytokines that are ready for release that attract and drive the immune response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the 3 functions of dendritic cells [3]

A
  1. phagocytosis
    • not as much as macrophages, dendritic cells are more APCs
  2. migration
    • sit in tissues constantly sampling the environment
    • when activated, will travel to draining lymph nodes
  3. antigen presentation (APCs)
    • presents to CD4 T cells
    • initiates adaptive immune response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Adaptive Immunity

  1. describe the humoral adaptive response [2]
  2. describe the cellular adaptive response [4]
A
  1. humoral adaptive response
    • B cells
      • release antibodies (immunoglobulins) that kill extracellular pathogens (e.g. bacteria)
  2. cellular adaptive response
    • CD4 T cells
      • helper T cells
      • directs B cells and CD8 T cells
      • increases cytokine secretion
    • CD8 T cells
      • killer/cytotoxic T cells
      • targets intracellular pathogens (e.g. viruses)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Label the structures of an antibody on the following diagram: [4]

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

What are the 3 functions of antibodies? [3]

A
  1. opsonisation for phagocytosis
  2. activation of complement for lysis
  3. neutralisation of toxins and pathogen binding sites
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q
  1. How do antibody isotypes differ structurally? [1]
  2. Describe the features of the following antibody isotopes:
    • IgM [3]
    • IgG [4]
    • IgA [3]
    • IgE [2]
A
  1. differ in Fc regions
  2. lgM:
    • main antibody of primary immune response
    • low affinity
    • activates complement
  3. lgG:
    • main antibody of secondary immune response
    • higher affinity as part of secondary response
    • Activates Complement
    • binds Fc𝛾 receptor on phagocytes (opsonsises).
    • crosses placenta
  4. lgA:
    • “antiseptic paint”
    • present in secretions and lines epithelial surfaces
    • neutralises by blocking binding of pathogens
  5. lgE:
    • high affinity binding to mast cells through Fc receptor
    • role in allergy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Optimal B cell response requires T cell help. What do T cells assist with? [5]

A
  1. clonal expansion of specific B cells
  2. progression to antibody secreting cells (plasma cells)
  3. progression to memory B cells
  4. isotype switching to IgG, IgA and IgE
  5. affinity maturation
17
Q

Describe the T Cell Receptor (TCR) and what it recognises [3]

A
  1. the receptor is on the surface of T cells and only recognises antigens when it is presented in a MHC molecule
  2. recognises short peptide lengths
18
Q

How is autoimmunity prevented? [3]

A
  1. B cells develop in the bone marrow and if B cell receptor binds strongly to “self” antigen in bone marrow, the cell will die by apoptosis
  2. T cells originate in bone marrow and migrate to thymus, and if T cell receptor binds strongly to “self” antigen in thymus, the cell will die by apoptosis
  3. activation of both cell types requires presence of danger signals to activate. if antibody/TCR engaged in absence of “second signal”, then cell likely to become anergic
19
Q

Describe the differences between MHC Class I and MHC Class II under the following headings:

  1. What type of T cell it presents to
  2. What type of cell it is found on
  3. What type of antigen it presents
A
  • Class I MHC
    1. ​​presents to CD8 T cells
    2. found on all nucleated cells
    3. presents intracellular antigen
  • Class II MHC
    1. presents to CD4 T cells
    2. found on antigen presenting cells
      • (dendritic cells, macrophages, B cells)
    3. presents extracellular derived antigen
20
Q

Organs of the Adaptive Immune System

  1. What are the primary organs and their functions? [4]
  2. What are the secondary organs? [4]
A
  1. primary organs:
    • thymus - T cell education
    • bone marrow - B cell education
  2. secondary organs:
    • lymph nodes
    • spleen
    • mucosal associated lymphoid tissue of GI tract (MALT) or the bronchial tract (BALT)
21
Q

Lymph Nodes

  1. location of B cells? [1]
  2. location of T cells? [1]
  3. location of macrophages and plasma cells? [1]
A
  1. primary lymphoid follicle
  2. paracortical areas
  3. medullary cords
22
Q

What are the functions of the spleen? [2]

A
  1. filters blood of senescent cells and blood borne pathogens
  2. important in response to encapsulated organisms and blood borne pathogens
23
Q

What are the 4 functions of the adaptive immune system? [4]

A
  1. provides specific antibodies to the innate immune system to enhance pathogen clearance
  2. provides cytokines to the innate immune system to upregulate activity
  3. finishes off the job of clearing pathogens
  4. develops a memory to prevent future infection
24
Q

Describe the secondary response to an infection [4]

A
  1. memory B cells and memory T cells already present at a high frequency
  2. memory lymphocytes have lower threshold for activation and actively patrol the sites of previous pathogen entry
  3. preformed antigen specific lgA prevents pathogen binding
  4. preformed high affinity lgG rapidly opsonises pathogen for phagocytosis

Week 2 - General Pathology (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions