immune system- med phys

largest immune organ

skin

external source of immunity

vaccines

internal source of immunity

moms pass it in utero

primary lymphoid organs

bone marrow

thymus

what is the function of bone marrow (in regards to immune)

make all lymphocytes that have functional receptors

what is the function of thymus (in regards to immune)

t cells go here to mature (so the receptor becomes functional)

secondary lymphoid organs

spleen and lymph nodes

lymph nodes

where lymphocytes and antigens meet

can be specialized depending on the area of the body

peyers patches

specialized lymph node

primary activation of killing an infection occurs in the...

spleen or lymph node

lymph node have dense regions of...

b cell or t cells

lymph nodes swell in response to

proliferating cells (sign of fighting infection)

spleen has areas with what cells

t cells

b cells

macrophages

spleen in response to stress

antigen presenting cells and macrophages increase and hang around the t cells and b cells of the spleen to wait to attack

chronic stress (in regards to immune)

shuts down the immune response

acute stress (in regards to immune)

elevates immune system

sex hormones (in regards to immune) examples

pregnancy makes MS symptoms better (estrogen suppresses)

pregnancy makes lupus worse (estrogen elevates)

4 major roles of the immune system

1. defense against infection-- dec immunity=infections; vaccines boost immune responses

2. defense against tumors-- immunotherapy of cancer

3. injure cells and induce pathological inflammation--allergic, autoimmune

4. recognizes and responses to tissue grafts and newly introduced proteins-- barrier to transplantation and gene therapy

2 types of immunity

innate-natural barriers and inflammatory response, born with these, automatic fight response (not specific)

adaptive- acquired, highly specific or learned

3 types of immune defenses

innate immunity- natural barriers (can cross this through digestion, injection, inhalation)

innate immunity- nonspecific inflammatory and cellular mediators (know its foreign but dont care about what type of foreign substance)

adaptive immunity- antigen specific cellular mediators (t cells and B cells)

examples of innate immunity nonspecific inflammatory and cellular mediators

plasma protein systems (complement and clotting cascade)

granulocytes, monocytes, NK cells, mast cells

examples of adaptive immunity antigen specific cellular mediators

t and b cells

first line of defense- natural barriers and chemicals

skin

lining of mucosal tracts (can get rid of pathogens)-- gastro, urinary, respiratory

first line of defense- biochemical barriers

-make and secrete substances to kill bacteria (sweat, saliva, tears, earwax) which are antimicrobial peptides

-normal microbiome of the body- inhibits colonization of pathogens and releases chemicals to prevent infection

3 types of antimicrobial peptides

cathelicidins, defensins (alpha and beta), collectins (lungs)

healthy bacteria in the vagina

lactobacillus

what do healthy bacteria in the intestines produce

ammonia, phenols, and indoles

what happens when natural barriers are breached

inflammatory response

causes of the inflammatory response

infection (danger signals)

mechanical damage (tissue injury)

ischemia

nutrient deprivation

extreme temps

radiation

2 components of inflammation

cellular and chemical

is the inflammatory response innate or adaptive

innate and nonspecific

how does the inflammatory response take place

same way regardless of the type of stimulus or whether exposure to the same stimulus took place in the past

speed of the inflammatory response

rapid and immediate

does the inflammatory response have memory cells

no b/c it is an innate response

what are memory cells

t cell and b cells

specific to the adaptive immune response

4 symptoms associated with inflammation

heat

redness

swelling

pain

3 basic roles or functions of inflammation

dilute toxins

carry plasma proteins and leukocytes to injury site

carry bacterial toxins and debris away from site

5 end GOALS of inflammation

-limit and control inflammatory process (so its not chronic bc chronic inflammation causes pathology)

-prevent/limit infection and damage

-control bleeding

-interact with adaptive immune system to finish the job

-prepare injured area for healing (with factors like fibrin)

where does inflammation occur

with almost every disease

what 4 things occur to give off inflammation symptoms

-capillaries widen to inc blood flow and it gives off heat

-capillaries more permeable (pull apart) to release fluid and cells enter which gives redness and tenderness

-attracts WBCs to injury site to give tenderness and swelling

-systemic response of a fever and proliferation of WBCs which can cause pain

5 cellular mediators (cells that come in and do job) of inflammation

mast cells

granulocytes

monocytes + macrophages

natural killer cells and lymphocytes

cellular fragments/platelets

does inc neutrophils indicate infection

not necessarily but it means inflammation

biochemical mediators of inflammation are responsible for

vascular changes and regulate activity and location of other inflammatory cells

5 examples of biochemical mediators of inflammation

histamine

chemotactic factors

leukotrienes

prostaglandins

platelet activating factor

all the biochemical mediators of inflammation come from

mast cells

biochemical mediators are stored or released immediately?

can do either

cytokines vs chemokines

chemokines are a type of cytokine; both regulate innate or adaptive resistance by affecting other cells

chemo- call cells or push them away; control cell movement

cytokines- dictates who comes and how they will behave

chemokines + cytokines have ______ actions

pleiotrophic- same molecule may have different behvaiors depending on specific target cell it binds to

are chemokines and cytokines pro or anti inflammatory

can be either

are chemokines and cytokines synergistic or antagonistic

can be either

3 cytokine examples

interleukins, interferons, tumor necrosis factor

chief cell communicator in inflammatory mediator response

cytokines

principal mediator of communication between cells in the inflammatory response

interluekins (ILs)

what produces ILs and in response to what

macrophages and lymphocytes in response to bacteria or another stimulant of inflammation

ILs help regulate

inflammation

IL-1

proinflammatory cytokine that causes fever

IL-6

proinflammatory cytokine

helps with healing (wound)

IL-10

anti-inflammatory cytokine

Transforming Growth Factor-beta (TGF-β)

anti-inflammatory cytokine

what does a fever do

kill bacteria and help immune system function

interferons protect against _______ infections

viral

interferons are produced and released by...

virally infected host cells in response to the presence of DS RNA

do interferons directly kill viruses

no but it prevents them from infecting healthy cells

helps regulate autoimmune diseases and cancer

INF-alpha

INF-beta

interferons that induce the production of antiviral proteins

INF-gamma(Y)

interferons that increase microbiocidal activity of macrophages

briefly explain how an interferon works

cell that is infected with a virus produces interferons which tells neighboring cells that they are infected and to start defenses (by binding to uninfected cell and induces synthesis of antiviral proteins)

upreg. of antiviral proteins bc of virus present in environment

the antiviral protein blocks the viral nucleic acid synthesis

TNF-alpha (the effects of it)

has local and systemic effects

-induces fever

-inc making of proinflammatory proteins

-causes cachexia (muscle wasting) and clotting

what is responsible for fatalities from shock and sepsis caused by gram negative bacterial infections

TNF-alpha

chemokines control...

chemotaxis (cell movement)-- when to leave, go, or stay

type of cytokine that stimulate WBCs movement

chemokine

chemokines regulate ____ from what to what?

the migration of WBCs from blood to tissues (chemotactic factors)

what produces chemokines and in response to what?

macrophages, fibroblasts, and endothelial cells during inflammatory response and homeostatic proliferation

how many chemokines exist

over 40 (less than the number of cytokines)

are mast cells apart of the innate or adaptive immune system

innate

most important cellular mediator of inflammation

mast cells

where are mast cells found and what are they made of

bags of granules in loose CT near BV

skin, digestive lining, respiratory tract (places with allergic responses)

two ways to activate mast cells

physical injury, chemical agents, immunologic processes, and toll-like receptors

chemicals --degranulation (immediate) or synthesis of lipid-derived chemical mediators (delayed)