test 11 immune systems test Flashcards
what are antibodies
small y-shaped proteins
antibodies are the same i ___- except
sam in structure except the two tips of y, which have heavily variable structures
the tips of the y have nearly
nearly infinite shapes and can recongnzie practically every molecule
the stem of the y is called he
Fc region
the branches of the y are called
the Fab regions
pathogens are broken down by phagocytes into
shreds called antigens
antigens are sensed by
antigen binding sites on antibodies
what are antibodies also called
immunoglobulins (Ig)
the five types of immunoglobulins
IgG, IgM, IgD, IgA, IgE
the most common type of immunoglobulin
igG
what are B cells
a specific type of white blood cells
what is the primary purpose of B cells
is to create antibodies
Each B cell creates just
just one specific antibody through V(D)J recombination
what happens once a B cell’s antibody has recognized a pathogen and “treated” the body
the B cell turns into a memory B cell
where to memory B cells go
travels to a lymph node and lies dormant until the next time that same antigen is spotted
what happens the next time the same antigen is spotted
the dormant cell rapidly creates antibodies, faster than the last time the body saw this antigen
the same time the antigen is spotted the body is
the body is quickly cured (often even before you feel sick)
B cells thing is the principle in which
vaccination works
what are T cells
another type of white blood cells
T cells are produced by
the thymus
why are T cells called T cells
because they are produced by the thymus
where is the thymus
just superior to the heart
like B cells, T cells are also
antigen specific
T cells have special receptors on their membranes called
TCRs
TCRs
T cell receptors
what do TCRs do
look for digested pieces of stuff that macrophages and dendritic cells have broken apart in phagocytosis
if the digested stuff found by the T cells is bad…
the T cell will trigger some events from the different types of T cells
Some T cells are
cytotoxic T cells, helper T cell, regulatory T cells
what will cytotoxic T cells do when triggered
they will hunt down and kill cells that contain a certain antigen
what will helper T cells do when triggered
begin producing cytokines that will attract B cells, cytotoxic T cells and macrophages and cause white blood cells hematopoiesis
what will regulatory T cells do when triggered
shit down other T cells at the end of a immune response
each antigen has smaller regions called
epitopes
epitopes can be recongnized by what
the variable sequence, or paratope of antibodies can recognize
do most pathogens have many epitopes
yes
why do most pathogens have many epitopes
so they can recognized by many antibodies
what is the primary purpose of antibody binding
to promote opsonization
what are the 4 ** other mechanisms that help fight pathogens
- neutralization
- agglutination
- precipitation
- complement activation
the Fab region (s) of an antibody bind to
the antigen
what happens after the Fab region (s) of an antibody binds to the antigen
the Fc region dangles off
many phagocytes have special receptors called
opsonin receptors
what do opsonin receptors do
increases the chemical attraction between themselves and dangling Fc regions
opsonization makes marked antigens
more “delicious-looking” to phagocytes
what is neutralization
refers to when an antibody physically blocks the antigen from having its effect
one example of antibody neutralization
is bacterium corynebacterium diphtheriae
what does bacterium corynebacterium diphtheriae do
secrets a small protein called diphtheria toxin
the diphtheria toxin can
enter cells and break the eEF-2 protein
what is the eEF-2 protein
a vital part of protein synthesis in human cells
diphtheria toxin is
an antigen that has an antibody
what the antibody for diphtheria do
blocks diphtheria toxin from binding to receptors and entering the cell
the antibody for diphtheria causes eEF-2
it is never turned off, meaning that the immune system is neutralized by antibodies
what is agglutination
the clumping together of molcules
some antibodies will cause bacteria to
to stick together in large groups
what can agglutination do
- antibodies can cause microbes to stick together
- makes it easier for phagocytes to engulf them
agglutination plays a major role in
blood types
types of blood people can have
type A, B, AB , O
what does type A blood have
have A antigen of RBCs and b antibody in blood
what does type B blood have
have B antigen of RMCs and A antibody in blood
what does type AB blood have
have A and B antigen on RBCs and no antibodies in blood
what does type O blood
have neither A nor B antigen on RBCs, both antibodies in blood
what happens if a person gains a transfusion of blood with an antigen they have antibodies for
the antibodies will cause RBCs to agglutinate and then lyse
what happens when RBCs agglutinate and then lyse
free hemoglobin clogs the kidneys and makes them shut down
some antigens, usually ____ are soluble
usually harmful pieces of virus, are soluble
what can soluble antigens do
“hide” across the body by dissolving in serum
antibodies can bind to soluble antigens and
force them out of solution and cause them to form a solid precipitate
when antibodies cause soluble antigens to form a solid precipitate
makes the antigens easier targets for phagocytosis
in order for precipitation to work you need
roughly equal parts of antigens and antibodies are required for this to work
precipitation is often coupled with
coupled agglutination
complement pathway
a shared component of the innate and adaptive immune system
complement pathway can be turned off and on using
by the presence of PAMPs or by a signal from antigen-antibody complexes
in short, cytokines released because of ________
because of PAMPSor antigen-antibody complexes will leads to a cascade
cytokines released because of PAMPS or antigen-antibodies will lead to what cascade
a cascade that makes many different proteins together and forms a giant pore in a pathogen’s membrane, killing it
what are autoimmune diseases
a broad class of diseases where the body attacks itself
what happens when there is an autoimmune disease
antibodies in the body mistake “self” cells for “nonself” cells and begins attacking them
autoimmune disease usually causes one of which 3 thing
- tissue damage
- increased tissue growth
- altered tissue function
the immune responses
primary and secondary
primary immune response
the first time the body sees an infection and it takes a while to “gather the troops”
secondary immune response
each subsequent response, it happens much faster and much stronger
what do vaccines do
expose the body to PAthogen without getting you sick
to do a vaccine a bacterium or virus has to be specially prepared by …
attenuated
killed/inactivated
subunit
attenuated vaccination
bacterium/virus is alive, but has been genetically modified in such a way that its “bad” genes have been removed
killed/inactivated vaccination
bacterium/virus is grow in the la and then killed by adding heat or formaldehyde. dead specimens are injected
subunit vaccination
bacterium/virus is grown in lab. only one part )is placed into vaccine and injected
which parts are usually injected in subunit vaccination
(usually a capsid in . viruses and a membrane or wall component in bacteria- just a single epitope
examples of attenuated vaccines
MMR,Measles, Mumps, Rubella
Pros of attenuanted vaccines
- only a small dose
- no booster required
- gives strongest immunity
cons of attenuated vaccine
- must be refrigerated
- miniscule risk of mutation to regain pathogenicity
- may cause adverse reaction
examples of killed/inactivated vaccines
polio
pros of killed/inactivated vaccine
- no risk of mutation to regain pathogenicity
- does not need to be refrigerated
cons of killed/inactivated vaccines
- much larger doses required
- often needs “booster” shots
- may cause adverse reaction (less likely than attenuated”
subunit vaccine example
Heb B
pros of subunit vaccine
- no risk of mutation to regain pathogenicity
- does not need to be refrigerated
- not likely to overwhelm immune system and cause adverse reaction
cons of subunit vaccine
- gives weakest immunity because only one or a few epitopes recognized
- much larger doses required
- often requires boosters
which is the only disease we’ve eradicated
smallpox
vaccines also provide what
active immunity
what s active immunity
vaccines cause you body to make memory B cells that recognize antigens and spring into action the next time you encounter them
active immunity generally lasts
for life
other medical treatments are designed around
passive immunity
when is passive immunity
used in time-sensitive cases or when a patient has a weak immune system already
examples of time sensitive cases
snakebites, tetanus
what is passive immunity
involves inject neutralizing antibodies, harvested from a different host, into the patient
passive immunity lasts…
days to months and is temporary
the four types of immunity
active neutral, passive neutral, active artificial , passive artificial
active neutral immunity
patient catches the disease, develops his/her own antibodies, and builds up memory B cells that will fight it the next time
passive neutral immunity
infant patient drinks breastmilk receives mother’s antibodies, had temporary protection from many diseases
active artificial
patient receives a vaccination of a attenuated or dead vaccine or a subunit, gains memory B cells without actually fighting
passive artificial
patient receives injection of antibodies from donor organisms (horses,pigs) that neutralize antigens and give temporary immunity
body’s main defense can be broken into what 2 parts
innate immune response, adaptive immune response
innate immune response is
nonspecific had 2 parts
2 parts of innate immune system
- physical/chemical barriers to keep contaminants out
- responses like macrophages, inflammation, fever to keep microbes at bay
adaptive immune response
how the body learns to specifically target and eliminate contaminants
95% of infections
begin on the mucous membranes
5% of infections
result from vector bites
what does the skin normally act like
a solid barrier that stops bacteria from getting inside the body
the outer layer of the skin is
coated in keratin
what does keratin do in the skin
works with other lipids and proteins to form a tight seal, separating inside from out
the outer cells of the skin are
continuously shedding and taking attached microbes with them
what does the skin secrete
waxy,oily substance called sebum
sebum gives the skin what pH
roughly 5.5, acidic compared to body pH
body/ bloodstream pH
7.4
the change in pH from sebum can
denature enzymes in bacteria, slowing their function
aside from the skin, where else does the body use pH to denature bacterial enzyes
saliva, stomach, vagina,
pH saliva
roughly neutral** check it
pH stomach
varying pH of 2 after a meal, 3.5 closer to rest
pH vagina
resting pH of 4
what are some other physical barriers to keep microbes out
mucus, urination, defecatation, vomiting, tears, hairs, cilia
where is mucus found
airway, esophagus, stomach, intestines, cervix in females
what does mucus do to help be a physical barrier
microbes stick to it and are broken down by proteins and or expelled from the body
what does urination, defecatation, vomiting and tears do
all wash microbes out of the body
hairs in the ____ and cilia in the ___ stop
nose, windpipe, stop microbes from entering the lungs
how does hair and bacteria stop cilia from entering the lungs
bacteria are pushed up and away from the lungs through the mucociliary elevator. extremely sensitive nerves in the air way ill force a cough reflex if a particle is detected
lysozyme is found where
in tears, mucus , breast milk, saliva
lysozyme break down what
peptidoglycan into smaller subunits, effectively killing the bacteria
what is peptidoglycan
main component of bacteria cell walls
the human body has many
bacteria living on it in mutualistic relationship
bacteria living on humans in a mutualistic relation
collectively called normal flora
what are some benefits that bacteria can cause for the body
- create nutrients that the body can’t normally provide
- competition for space and nutrients, making it hard for bad bacteria to thrive
- creaet compounds that kill other bacteria
- modify the pH of an area to make it inhospitable to other bacteria
example of nutrients created by bacteria the body can’t normally provide
B12
the human body has about how many human cells
10^13
the human body has about how much bacteria
10^14
phagocytes
white blood cells that eat and destroy foreign contaminants in phagocytosis
types of phagocytes
neutrophils, dendritic cells, macrophages
neutrophils
eat bacteria
macrophages
eat everything that dosen’t have proper ID
dendritic cells
eat surroundings that show PAMPs
macrophages and dendritic cells
present digested gut sto surrounding cells, ecspecially T cells
steps of phagocytosis 1-3
- chemotaxis and adherence of microbe to phagocyte
- ingestion of microbe by phagocyte
- formation of a phagosome
steps of phagocytosis 4-7
- fusion of the phagosome with a lysosome to form phagolysosome
- digestion of ingested microbes by enzymes
- waste created with indigestible material
- digest waste materials
the immune system looks for
certain microbe-associated patterns
what patterns do the immune system look for
PAMPS
PAMPs
pattern-associated molecular patterns
examples of PAMPs
peptidoglycan LPS Flagellin Double-Stranded RNA Glucans
what is peptidoglycan (as a PAMP)
the main bacterial cell wall component
why is peptidoglycan a special chemical
it surrounds the membranes of bacteria
what is LPS
the main bacteria membrane component
LPS
lipopolysaccharides
LPS are long chains of..
sugars that attach to membranes of bacteria that have a thin peptidoglycan layers
what is flagellin
a protein in bacteria flagella
many bacteria indeed have
flagellum or multiple flagella
what does flagellum do
help them move through the body
the main protein in flagellum
flagellin, which is also recognized as a PAMP
glucans
the major component of fungal cell walls
PRRs
pattern recognition receptors
what are PRRs
proteins found on the plasma membranes of macropahes
what is the job or PRRs
to recognize PAMPS
two main types of PRRs
phagocytosis receptors, TLRs
phagocytosis receptors
PAMP binding that leads to the onset of phagocytosis
phagocytosis receptors are only found
in pagocytes
TLRs
Toll-like receptors
toll-like receptors are
PAMP binding that leads to the activation of genes coding for cytokines
what are cytokines
signalling proteins
where are TLRs found
phagocytes, epithelial cells, and more
are there many kinds of TLRs that each recognize specific microbial components yes
yes
each TLR triggers
some release of cytokines that cause many things to happen
cytokines are small______ produced by ____
proteins produced by white blood cells
cytokines could be
autocrine, paracrine, endocrine
autocrine cytokines
act on the blood cell that secretes them
paracrine cytokines
act on nearby cells
endocrine cytokines
travel long distances in the body
cytokines can cause what different things to happen
- vasodilation of blood vessels
- up-regulation or down regulation of genes
- white blood cell hematopoiesis
- production of antibodies
- apoptosis
- inhibition of viral replication
on important type of cytokines
chemokines
what do chemokines do
attract molecules through chemical signals
two main categories of chemokines
homeostatic , inflammatory
homeostatic chemokines
attract various types of white blood cells to the area and invoke diapedesis
what is diapedesis
jumping through the walls of a vessel into the infected tissue
white blood cells are chemically attracted to
homeostatic chemokines
inflammatory chemokines
initiate the inflammatory response by causing vasodilation, leading to more blood and red blood cells in the area
inflammation can be
acute (quick onset) or chronic (long term)
signs of inflammation
redness, heat, swelling, pain
why are cytokines usually created
to recruit WBCs, which release more cytokines that recruit more WBCs in a positive feedback loop
the body is supposed to keep the cytokine feedback loop
localized and shut it off at a certain point
what happens if an infection gets too big
the body dosen’t shut down cytokines.. leading to a cytokine storm
the result of a cytokine storm
widespread inflammation
what can widespread inflammation lead to
ARDS
what is ARDS
acute respiratory distress syndrome
ARDS can lead to
death
cytokine storms can also cause
damage to blood vessels when they dilate too much and for too long
the damage of blood vessels in a cytokines storm can lead to
blood spilling in the extracellular space
blood spilling in the extracellular space can cause
reddish splotches on the skin, and it will also lead to decreased oxygen levels which may lead to shock
sepsis
when chemicals released into the bloodstream to fight infection trigger inflammatory responses throughout the body
fevers are invoke by
pyrogens
pyrogens can be classified as
endogenous or exogenous
exogenous pyrogens
like LPS, come from outside and bind to PRRs, to trigger the release of endogenous pyrogens
endogenous pyrogens
like interleukin-1 (IL-1) and (IL-) , are cytokines made by macropages in response to exogenous pyrogens
where do endogenous pyrogens travel to
the hypothalamus in brain, which sends hormone signals across the body to increase temperature
fevers help with
- stop bacteria growth by denaturing
- increase the ability of certain macrophages to do their jobs by altering the membrane fluidity
