Immune System Flashcards
1
Q
Define innate immunity
A
- organs, tissues, & cells of the immune system that you are born with
2
Q
Define acquired immunity
A
- immunity that develops during your lifetime
3
Q
Define active immunity
A
- develops in response to an infection (natural) or vaccination (artificial)
4
Q
Define passive immunity
A
- develops after you receive antibodies from someone (natural through breast milk) or somewhere else (artificial from medicine)
5
Q
Phases of an immune response
A
1) recognition (immune system recognizes an intruder)
2) amplification
3) effector phase (removal of antigens)
4) termination phase (immune system stands down)
5) memory (generation of long-lived T- & B-lymphocytes)
6
Q
Characteristics of innate immunity
A
- 1st line of defense, managing most threats
- early defense to prevent spread, elimination of pathogens & imitate adaptive immunity
- includes internal & external defenses
7
Q
External defense mechanisms
A
- anatomical/physical barriers (skin, mucus, cilia lining, & coughing/sneezing)
- chemical/biochemical barriers ( lysosomes, ear wax, stomach acid, & natural floria of organ systems)
8
Q
Internal defense mechanisms
A
- soluble factors (cytokines & chemokines)
- cellular components (phagocytes, neutrophils, monocytes, & natural killer cells)
9
Q
Describe soluble (inflammatory) mediators
A
- part of the complement system: biochemical network of more than 30 plasma proteins
- can coat the microorganisms with markers to allow the white blood cells to target them
10
Q
Define phagocytes
A
- are white blood cells/leukocytes
- involved in nonspecific or innate immunity
- readily ingesting/killing pathogens
11
Q
Define granulocytes
A
- have granular appearance
- short lifespan of 2-3 days
- neutrophils are a granulocyte
12
Q
Define monocytes/macrophages
A
- have lifespan of months to years
13
Q
Describe neutrophils
A
- derive from bone marrow
- short lived
- predominate leukocytes in the blood
- 1st to arrive at site of infection & significantly increase in number during a response
- attract monocytes
- dies following phagocytosis = pus
14
Q
Describe monocytes
A
- large, long-lived cells
- originating from bone marrow
- migrate to tissues following immune response then mature into macrophages (large eaters)
- clean up debris & kill any remaining damaged or large bacteria
- rely on cell-surface receptors
15
Q
What do eosinophils do
A
- they respond during allergic reactions
16
Q
What is the importance of basophils & mast cells
A
- they are important in allergic response
17
Q
Describe lymphocytes
A
- circulate in tissues, peripheral blood, & lymphatic system
- respond to viral infections
- include natural killer cells, B cells, & T cells
18
Q
Describe natural killer cells
A
- large lymphocytes, found in blood stream & spleen
- kill viruses, intracellular microbe infected cells, & tumor cells
- function more effectively with helper T cells
- express activating/inhibitory receptors on surface which target cells
19
Q
Describe dendritic cells (DCS)
A
- messenger between innate & adaptive immune system
- present in cells in contact with external environment, aka the skin (langerhans cell)
20
Q
Characteristics of adaptive immunity
A
- recognizes threat, promotes effective response, destroys threat, & establishes memory
- initiates after innate immunity & develops over lifetime
- creates immunological memory of pathogen to enhance future reaction to the same pathogen
21
Q
Define antigen
A
- any foreign material
- examples: bacteria, virus, & parasite
22
Q
Describe B cells
A
- arise & mature from bone marrow
- fight bacteria & viruses by making Y-shaped proteins (aka antibodies)
- require support from T cells
23
Q
Describe antibodies
A
- they are presented to T cells
- are pathogen specific
- mark cells for destruction
24
Q
Define plasma B cells
A
- large cells, produce antibodies in response to a specific antigen attack - effector cell
25
Define memory B cells
- long-lived cell, rapid response to future attacks
26
Describe T cells
- originate in bone marrow, travel to thymus for maturation
- each has a specific receptor for a specific antigen and can differentiate into several effector T lymphocyte subsets
27
What are the 4 types of T cells and what do the do
Helper T cells: activate other immune cells, release cytokines & help B cells produce antibodies, shapes & regulates immune response
Killer T cells: releasing cytotoxic granulates into target cell to kill a specific target antigen
Memory T cells: long-lived, form following an infection, proliferate quickly upon re-exposure
Regulator/Suppressor T cells: shut off the immune response when no longer needed
28
Define humoral immunity
- also considered B cell immunity
- pathogen located in blood plasma & lymph, free floating & easily accessed
- bacteria & virus
- creates specific antibodies & immunoglobulins, B cells differentiate & proliferate into plasma cells & memory B cells
29
Define cell mediated immunity
- also considered T cell immunity
- pathogen located in cell, destroy microbes in cytoplasm or phagocytic vesicles of infected cells
- bacteria, virus, protozoa, parasite, or cancer
- can be harmful to the host, rejection & autoimmune disorders
30
Define primary immune response
- the first time an antigen is introduced to the body
- 10-17 day lag between initial exposure & an effect from the immune system
31
Define secondary immune response
- subsequent exposure to the same antigen
- the response is faster (2-7 days) with greater magnitude
- antibodies in the secondary response have a greater affinity for the antigens
32
Factors that alter the immune system
- age
- medications
- nutrition
- environmental pollution
- exposure to toxic chemicals
- trauma
- burns
- sleep disturbance/stress
- presence concurrent illness/disease
- splenectomy
33
Factors that increase exposure to pathogens
- urinary catheters
- nasogastric tubes
- endotracheal tubes
- chest tubes
- PICC line
- external fixation devices
- implanted prostheses
- social & sexual practices
34
What is the Wear & Tear Theory
- organs composed of cells that cannot regenerate will eventually "wear out"
35
What is the Genetics theory
- aging is genetically determined
36
What is the Oxidative (free radical) theory
- based on chemical nature & wide presence of free radicals causing DNA damage & cellular oxidative stress
37
What is the Telomere Aging Clock Theory
- telomere act to signal onset of cell senescence
38
Changes to innate immunity due to aging
- exterior defenses are affected by thinning if the skin
- phagocytes (neutrophils & monocytes/macrophages) show a decrease in function with aging
- eosinophils accumulate in fewer numbers at sites if infection with age
- basophils are characterized by reduced degranulation with aging
39
Changes in acquired immunity due to aging
- difficulty mounting protective immune responses to newly encountered antigens due to decreased production of T & B cells
40
Define psychoneuroimmunology
- study of interaction between psychological processes & nervous/immune systems of the body
41
How does stress alter your immune response
- when physically or emotionally stress, your body releases epinephrine & cortisol which increase the production of pro-inflammatory cytokines which are typically released in response to an infection or injury
42
How can exercise enhance the immune system
- immune system is enhanced during moderate exercise
- prevents neuroendocrine & detrimental immunologic effects of stress
43
How can exercise suppress the immune system
- with prolonged/intense exercise it suppresses lymphocytes which suppress natural killer cell activity & oxidative modifications of DNA impairment
44
What is important to know about exercise & infection
- exercise during the incubation period of the infection appears either to have no effect or to increase the severity of infection
-intense exercise in young subjects causes suppression of the immune system but not for aged populations
44
What is important to know about exercise & infection
- exercise during the incubation period of the infection appears either to have no effect or to increase the severity of infection
-intense exercise in young subjects causes suppression of the immune system but not for aged populations
45
How to determine whether to exercise during a viral/bacterial infection
- if symptoms (sx) are located above the neck, exercise cautiously at half speed & after 10 min if sx alleviate then resume usual exercise
- if symptoms (sx) are located below the neck, exercise should not be initiated for 7-14 days bc of risk of dehydration, prolonged illness, or more serious complications
