exam 3 Flashcards
lines of defense, symbiosis
what are the 3 lines of defense
(1)Exterior, (2)phagocytes and inflammation, and (3)adaptive immunity
What lines of defense are nonspecific
(1)exterior, (2)phagocytosis and inflammation
What lines of defense are specific
adaptive immunity
Eyes- tear ducts
contain lysozymes that hydrolyze peptioglycane
Nose
The most common way for bacteria to enter is by removing particles via cilla in the nasopharynx
Pharynx
Rich in microbes and containing microbial antagonism
Microbial Antagonism
residents’ microbiota that outcompetes transeit microbiota
Mucociliary Escalator
sticky mucus constantly being made and moving up the throat via cilia beating. hence the mini coughs we have
Smoker mucociliary escalator
Toxins from smoke inhibit the beating of cilia and, therefore, mucus doesn’t move up the throat, causing smokers to cough. NOTE: doesn’t inhibit the making of mucus
Lungs
Not axenic! Full of white blood cells that engulf and destroy foreign things!!
Stomach
has a high pH killing microbes,
some exceptions i.e acidophiles
Urine
peeing rid bacteria
skin
acts like a barrier, and shed 100 skin cells a day
Why is red blood stem not a true cell?
b.c doesn’t have a true nucleus
where do blood stems come from?
Bone marrow
3 types of phagocytes?
Neutrophil, Eosinophils, monocytes
Neutrophil
common blood cell, known as polymorphonuclear,
Eosinophils,
assoicated with allergies, worm infections
monocytes
referred as macrophage when in other tissue
subtype of cytokine
chemokine! and attract phagocytes
what are cytokine?
messenger molecules of the immune system
4 types of cytokine
interferon, prostaglandins, leukotrienes, histamine
Prostaglandins and leukotrienes both
stimulate vasular permeability
Histamines
promote vasodilation
vasodilation
when blood vessels widen, increasing blood flow and bringing more heat to trunk regions, i.e., arms, legs, etc. This causes rednesss and heat and increases vascular permeability.
Vascular permeability
vessels are “stretched” causes swelling and blood leaking into intracellular spaces of cells, increasing pressure and pain receptors
damage cells release
Cytokine, which then attracts phagocytes.
How do phagocytes work?
Phagocytes bind to the foreign thing, where phagocytes engulf it making phagosomes. In the inside of any phagocytes are lysosomes that fuse with the phagosome killing the bacteria(foreign substance). The final step is elimination, where through exocytosis dead bacteria are released.
Characteristics of interferon
non-specific, turns in antiviral genes hence a transcription factor.
How does interferon work?
When a virus enters a cell, the interferon gene is activated. The gene is transcribed and translated to produce interferon molecules, which are then released. These interferons signal neighboring cells to activate their own interferon genes, leading to the production of antiviral proteins. These proteins help block viral replication, protecting the surrounding cells from infection * think of alarm system
arteries
blood moves away from heart
veins
blood towards the heart
payer’s patches
a small cluster of lymphatic tissue in the intestine, and it is rich in microbe, and conducts surveillance of the GI tract.
lymphs nodes….
help mature white blood cells, filter the blood from pathogens and waste, and are located all over the body to protect from pathogens
lymphocytes
type of leukocyte that fight against pathogens
lymphatic system
composed of lymphatic vessels that conduct the flow of lymph.
Antigen
any foreign molecule that causes an immune responds
an antigen can have many…
epitope, *antigen and epitope is interchangeable term
antibody
proteins that bind to antigens and facilitate their removal
3 functions of phagocytes
1.) phagocytosis
2.) cytokine release
3.) antigen presentation
MCH1 is found in
all nucleated cells (phagocytes included!!)
MCH2 displays
is for all displayed non-self epitope
Why does MCH1 display non-self?
displays virus to show the immune system when there is a intracellular pathogen
Helper Cells other names
Th cells, CD4 cells,
Cytotoxic T-cells other name
TcCells, T8 cells, CD8 T cells, T8 lymphocytes
what is the specific function of CD4
is to bind to MCH2 receptors to simulate a humoral immunity and fight extracellular pathogens
The function of MCH1 is to..
is to display intracellular pathogens on nucleated cells and phagocyte
The CD4+ binds to
MCH2
CD8 binds to
MCH1
Cytotoxic cells are simulated by recognizing and binding to
MCH1
What are the pros of plasma cells being shorted lived?
since they are short lived they are produced antibodies faster, and therefore work faster
What are the cons of plasma cells being shorted lived?
There are rapid clearance and i.s doesn’t remember past infections aka ni immunity
what are the pro of long-lived memory B cells
they help build immunity aka they remember past infections!
what are the cons of long-lived memory B cells
they divide slower and hence take a long time to start working ther first time around
Where are perforin and granzymes found
found in cytotoxic/TcCells
BCR
are antibodies. We call them BCR when they are attached, and antibodies detached
How many regions of Fab/variable region are there
2 regions
Fc region is
the constant region doesn’t change. It interacts with the immune system
Neutralization
physically blocks foreign things
Agglutination of bacteria
clumping of bacteria
Precipitation of dissolved antigens
clumping of antigen molecules
activation of complement activation
antibodies attract proteins to make pores, aka form the MAC, which makes many pores leading to apoptosis/cell lysis
Opsonization
antibody-enhanced phagocytes. This works because phagocytes can detect Fc constant
Since antibodies can make every possible epitope, what is the downside of this?
It starts attacking your proteins!! not fun
what does RAG do?
mix and matches the antibodies gene to make a variety of antibodies
how does antibodies know what is self and non self
There are autoantigens that recognize host proteins. They bind to the B-cell. If there is a match, it rids the antibody, if it doesn’t make the antibody, it is free to do its job!
B cells start as..what type of antibody?
IgM when are still attached
What is the role of lymph nodes?
help mature white blood cells
help filter the blood from pathogen and waster
located all over the body to protect from pathogens
Mucosa Associated Lymphoid Tissue (MALT)
Similar functions to lymph nodes but for mucosal and monitor exterior foreign cells.
Most to least common antibodies
IgG, IgM, IgA, IgE (Go Make A Egg)
what antibody is found in secretions?
IgA
What antibody can cross the placenta?
IgG
What antibody is associated with allergies
IgE
Which antibody dimerizes
IgA
Which antibody has pentamers
IgM
Which antibody provides passive immunity to babies via break milk
IgA
Adaptive Immunity
Mount your own immune responds to pathogen and vaccines
Adaptive Immunity examples
vaccines that trick your body to create immune response
Passively acquired
receive pre-formed antibodies from other.
examples of passively acquired
In babies, when they are breastfed, they receive antibodies from their mother(IgA)
or
IgG that crosses the placenta and gives babies maternal immunity.
What is Live “Attenuated” vaccine
When the pathogen is alive, but its ability to cause disease is impaired
What is Live “Attenuated” vaccine Pros and Cons
Pros: Don’t need a booster, large immune response (more robust).
Cons: Not easy to transport, risk of reverting!, not cheap!
What is the killed vaccine
The pathogen is killed, but it retains its full normal shape. It’s important to keep shape because every epitope is intact.
What are the killed vaccine Pros and Cons
Pros: easy to use, cheap
Cons: requires a booster as a 2nd line of defense, can clear it out, so the 3rd line of defense never kicks in:(
What is a Subunit Vaccine
individual antigens from the pathogen is used
What are the Subunit Vaccine Pros and Cons
Pros: can’t be reverted, easy to transport
Cons: not as robust, needs a booster
What is the Nucleic acid Vaccine
DNA or RNA encodes a pathogenic antigen is used, the patient cells produce the antigen by transcribing and translating ex. COVID vaccine
commensalism
An association between two organisms in which one benefits and the other derives neither benefit nor harm.
parasitism
one benefit, the other is hurt
Mutualism
both benefit
correlations
when 2 things are present together, but that doesn’t mean there is a relationship!
Necessity
Is the symbiont necessary for development? Can the host survives without it
Sufficiency
If, when the symbiont is removed from the host organisms, development stops, and when the symbiont is reintroduced into the host, does development continue where it left off?
Describe the relationship between the Hawaiian bobtail squid and V. fishceri
V. fisheri live in the squid’s light organ and provide light to limit shadow production.
What role does Quorum Sensing play in the interaction between V. fischeri and Euprymma scolopes
V. fishceri can sense when bacterial density is dense enough to fluoresce
How does V.fishceri avoid the Hawaiian bobtail squid immune system
V fishceri is gram-negative, which means it can survive in the squid’ mucus and V.fisheri is immune to the squids phagocytes
What type of virulence factors are more likely to help V. Fishceri survive in bobtail fish
Antiphagocytosis factors that prevent digestion by phagocytosis
We know what V. fischeri gains from its association with bobtail squid. What does bobtail squid have to gain from this association, and what type of association is this?
V. Fischer facilitates the physical development of bobtail squid/mutualism, and can avoid predation
Virulence
ability to cause disease
Koch Postulates
a set of criteria used to establish a causal relationship between a specific microorganism and a disease
1 step in koch’s Postulates
A suspected germ has to be present in every case of disease.
3 step in koch’s Postulates
The cultured germ must cause the disease when it is inoculated into a healthy experimental host.
2 step in koch’s Postulates
The suspected germ should be isolated and grown in pure culture.
4 step in Koch’s Postulates
The same germ must be re-isolated from the disease experimental host
In step 2 of Koch postulates remember that…
We must be able to culture the said disease, and a virus can’t be cultured, so it only works on bacteria and fungi.
Miasma
bad/poisoned air
What bacteria don’t follow the typical “the number of pathogenic bacteria in a patient is greatest during the most severe disease stage.
Bordetella pertussis, as they are most severe in the prodromal period.
Are B.Theta fecal coliforms?
No, because they are anaerobes
Can bacteria influence mammalian development?
True
What bacteria are most common in the gut of mice?
B.Theta
What do fold in the epithelial do?
They increase surface are therefore able to absorb more nutrients. More dense=better at absorbing minerals
Where do the nutrients go after?
the cardiovascular system
Epithelial cells in the fold are..
constantly shedding because more prone to infections
Stem cells in the fold
making new epithelial because it is constantly shedding.
Paneth cells
increase the vasculature of the intestine (aka expanding the number of blood vessels) and inhibits the growth of bacteria in the intestine.
When B. Theta interacts with Paneth cells what do they make?
Proteins called Ang4 (angiogenin)
Angiogenin is in the family
Angiogenesis
what does Ang4 do?
make blood vessels and are antimicrobial.
Why is Ang4 being antimicrobial important?
Kills other microbes except for B. Theta because B. Theta activates its produced!!
3 types of evidence- correlation
B. Theta happens to be in the small intestine and
there is a produce of Ang4 which makes more blood vessels
3 types of evidence- Necessity
If we remove B. Theta to see what happens when not present.
Germ free= little amount of blood vessels
Germ present= rich in blood vessels
3 types of evidence- Sufficiency
B. Theta later added and sufficient to restore normal development
What does the Mouse again, and what does the B.Theta gain?
B. Theta gains easy access to food and space
Mouse gains better nutrient absorption
The thymus, the spleen, and peyer patches are part of the
lymph system
Describe three mechanisms that help squid establish the symbiosis with V. Fishceri
- They beat their ciliated appendages on the light organ to attract bacteria
- They secrete a selective mucus for gram-negative bacteria
- The squid’s hemocytes do not recognize V. Ficheri
What are two ways V. Fischeri escape squids immune system
- V. fischeri are resistant to squid acid and oxidase enzymes that kill bacteria
- V. fischeri are not recognized by squid hemocytes that destory other bacteria.
fomite
inanimate object that spread disease
What are the 5 phases in intensity of sign of symptoms in order!
Incubations, prodromal, Illness, Decline, Covalescence
What is the incubations period
no sings or symptoms
what is the prodromal period
vague general symptoms, like itchy throat
what is the illness stage
most severe symptoms and signs
what is the Decline stage
decline signs and symptoms
what is the convalescene
no signs or symptoms
what bacteria does not follow this trend of signs and symptoms and why?
Bordetella pertussis doesn’t follow the graph; it peaks in the prodromal period, therefore doesn’t display severe symptoms
Direct contact
hand shakes, kissing, sex, bites
Indirect contact
drinking glass, toothbrushes, toys, punctures
droplet transmission
droplets from sneezing w/in 1 feet
Airborne
dust particles
waterborne
steams, swimming pools
foodborne
poultry, seafood, meat
mechanical vector transmission
on insect bodies flies, roaches
biological vector transmission
lice, mites, mosquitoes, ticks
Acute disease
disease in which symptoms develop rapidly that runs its course quickly
chronic disease
disease with mild symptoms that develop slowly and last long time
latent disease
within incubations period, they appear for a long time after infection
asymptomatic disease
disease w/out symptoms
communicable disease
disease transmitted from one host to another
contagious disease
communicable disease that is easily spread
noncommunicable disease
disease arising from outside of host or from opportunistic infections
local infections
Infections confined to a small region of the body
systemic infection
widespread infections in many systems of the body, travels from the lymph system
focal infections
infections that serve as a source of pathogens for infections at other sites in the body
primary infections
initial infection with a given patient
secondary infections
infections that follow primary infections, often by opportunistic pathogens
what do exotoxins
Bacteria secrete exotoxins like cytotoxins that kill the cell
Endotoxins
Dead gram-negative bacteria release exotoxins i.e lipid A that cause fever, inflammation, diarrhea, shock, and blood
DIC
disseminated intravascular coagulation
Hyaluronidase and collagenase
These are exoenzymes, not toxins! Bacteria release hyaluronidase which destroys polysaccharide b/n epithelial cells and collagenase, which invade deeper allowing bacteria penetrate deeper destroy collagen
Coagulase and Kinase
Bacteria produce Coagulase to form a blood clot. The clot is considered ectopic. The bacteria hide in the clot until the immune response is over, and grows. Bacteria later produces a kinase to break from clot
Phagocytosis block by capsule
A capsule around bacteria prevents phagocytes from binding to it, this is b/c bacteria starts producing human proteins tricking phagocytes
Incomplete phagocytosis
Bacteria after being engulfed (phagosomes) can’t be lysed via lysosome, so it just hides in phagocytes and grow due to the capsule surrounding the bacteria, ir bacteria release cytotoxins to kill phagocytes
membrane ruffling
Negative gram bacteria inject proteins via the type three secretions system
how does type 3 system
Bacteria inject effector proteins that manipulate the actin cytoskeleton to form an ectopic pseudopod shape to engulf bacteria. Once inside bacteria produce more effector proteins to return shape back to normal and bacteria goes deeper.
Why do bacteria do type three secretions?
To avoid the immune response, if bacteria produce proteins on the outside, it alerts the immune system that something is wrong and kills the bacteria.
What structure latches onto the human plasma membrane in type 3 secretion
translocom
what is one role of Paneth cells
They secrete Ang 4 upon contact with B. theta
Biofilm
extracellular matrix of organic molecules secreted by bacteria onto a surface
planktonic
free swimming
sessile
surface associated
chemotaxis
movement towards an attractant or away from a repellant
A bacteria basal body moving clockwise cw
tumbling
A bacteria basal body moving counter-clockwise ccw
running
True or False bacteria can switch cw and ccw contantly and can’t control this?
Yes!
what can bacteria control in terms of chemotaxis
They can control the speed or lower the tumbling
what kind of bonds are present in antibodies
disulfide bonds
IgG distribution and functions?
blood, lymph and fx is complement activations (MAC), opsonization is able to cross the placenta
IgA distribution and functions?
secretions and fx is opsonization
IgM distribution and functions?
lymph, blood, and BCR, 1st antibody made
IgE distribution and functions?
Blood and lymph and fx is allergic reactions and parasites
what is MAC
Membrane attack complex
