Fundamentals of Immune System: Flashcards
(57 cards)
1
Q
What is immunology the study of?
A
- The study of a host’s reactions when foreign substances are introduced into the body
2
Q
Define immunity:
A
- The condition of being resistant to infection
3
Q
Define Infection:
A
- Invasion or colonization of the host by pathogenic microorganisms
4
Q
Define disease:
A
- When an infection results in a change of health status
- When the normal functions of the body have been altered by the pathogen
5
Q
What two systems of immunity can the immune system be divided into?
A
- Innate (Natural)
- Adaptive (Acquired)
6
Q
What kind of defence system does innate immunity have?
A
- Has both an external defense system and internal defense system
7
Q
What is the first line of defence?
A
- external defense system.
8
Q
What are 5 examples of the external defence system?
A
- Sweat
- Sebum
- Tears
- Saliva
- urine
9
Q
What is the second line of defence?
A
-Internal defence system
10
Q
Define Phagocytosis:
A
- Process by which a phagocyte (cell capable of phagocytosis; certain white blood cells) surrounds and destroys foreign substances and removes dead cells
11
Q
What is the second line of defence made up of?
A
- Made up of cells and soluble factors
12
Q
What 5 Leukocytes are in peripheral blood?
A
- Neutrophils
- Eosinphils
- Basophils
- Monocytes
- Natural Killer cells
13
Q
What are 3 tissue cells?
A
- Macrophages
- Mast cells
- Dendritic cells
14
Q
What is a Neutrophils main function?
A
- Main function is phagocytosis resulting in the destruction of foreign particles
15
Q
What results in an increase of neutrophils?
A
- Acute infection results in an increase of neutrophils in circulating blood
16
Q
When can the number of Eoisinphils increase?
A
- Number increases in an allergic reaction or in response to certain parasitic infections
17
Q
What do Eosinphils regulate?
A
- Regulates mast cell function and the immune response
18
Q
What is the function of granules in a basophil?
A
- Granules have an important function in inducing and maintaining allergic reactions
19
Q
What do basophils regulate?
A
- Regulate some T-helper cell response and stimulate B cells to produce the antibody IgE
20
Q
What is called when basophils releases its granules?
A
- When granules are released, it is called degranulation
21
Q
What do monocytes become when they migrate to tissues?
A
- Can migrate to tissues and become macrophages
22
Q
What do Macrophages arise from?
A
- All macrophages arise from monocytes
23
Q
What are the two primary functions of macrophages?
A
- Antigen-presenting cell
- Produce signals required for the proliferation and differentiation of lymphocytes
24
Q
What do macrophages do in innate immune response?
A
- In the innate immune response, macrophages destroy microbes, have anti-tumor activity, remove intracellular parasites, perform phagocytosis, and produce cell mediator secretions
25
What do mast cells play a role in?
- Play a role in allergic reactions (inflammatory response)
26
What else can mast cells function as?
- Can also function as antigen-presenting cells
27
How are dendritic cells classified?
- Classified according to their tissue location
28
How do dendritic cells capture antigens?
- Capture antigens by phagocytosis and present the antigen to T lymphocytes to initiate the adaptive immune response
29
What is the most effective antigen-presenting cell?
- Dendritic cell
30
What do natural killer cells kill?
- kill cells tagged with antibodies
31
What two things are natural killer (NK) cells responsible for?
- Responsible for tumor surveillance
- Responsible for killing virus-infected cells
32
What type of WBC is a NK cell?
- A type of lymphocyte that does not have antigen receptors
33
What do NK defend against?
- Defend against cells that are virally infected, contain intracellular pathogens, and tumor cells
34
What happens when NK cells are activated?
- Once activated, they produce chemical signals to help recruit T cells (part of the adaptive immune system)
35
What are 4 signs of inflammation?
- Redness
- Swelling
- heat (caused by increased blood flow ((vasodilation)))
- pain
36
Why is inflammation important?
- Inflammation is a defense mechanism that is part of the internal innate immune response
- Works to remove these stimuli (pathogens) by enhancing phagocytosis
37
Where do pathogens go when they make it past the first line of defense?
- When pathogens get by the first line of defense (i.e. skin), they make it into the interstitial fluid
38
What is triggered when a pathogen makes it to the interstitial fluid?
- Triggers chemokines (messengers) to be released into the interstitial fluid
39
What is released from mast cells?
- Histamine is released from mast cells – Caused by direct injury, chemokines, or the pathogen itself
40
What does Histamine cause endothelial cells to do?
- Causes endothelial cells lining the capillaries to space out, making the spaces between them larger – vasodilation
41
What does Chemokines signal Neutrophils to do?
- Chemokines signal for neutrophils to gather and because the space between capillaries has increased, they are able to pass through
42
What is adaptive immunity characterized by?
- Characterized by specificity for each individual pathogen
43
What is adaptive immunity triggered by?
- Triggered by immunogens
44
What does adaptive immunity have the ability to remember?
- Ability to remember a prior exposure (memory)
45
What two responses is adaptive immunity made up of?
Made up of two responses:
- Humoral Immune Response
- Cell-Mediated Immune Response
46
What cells do lymphocytes have?
- B cells
- T cells
47
What are the two major populations in lymphocytes?
- t cells
- B cells
48
Where can lymphocytes be differentiated?
- Lymphocytes can be differentiated in the bone marrow and thymus
49
What on the surface of lymphocytes help distinguish each subpopulation?
- Proteins on the cells’ surface distinguish each subpopulation
- Clusters of differentiation (CD)
- Hundreds of CDs discovered but only a handful are considered the most important when identifying lymphocytes
50
What type of immunity is B cells?
- Humoral Immunity
51
What does humoral immunity mean?
- Pathogens are floating around in the fluid and have not infiltrated cells yet
52
Where are B cells produced?
- Produced in the Bone marrow
53
B cells have what type of immunoglobulins?
- B cells have membrane-bound immunoglobulins
54
What happens when B cells mature?
- When B cells mature, the genes coding for the membrane-bound immunoglobulins rearrange to produce a specific immunoglobulin (antibody)
55
What happens to B cells after maturation?
- After maturation, they circulate in the peripheral blood waiting to “bump into” the antigen the immunoglobulins are specific to – naïve B cell
56
What does In vitro mean?
Outside the body
57
What does in vivo mean?
Inside the body
