exam four (pathogenesis) Flashcards
an organism that causes diseases
pathogen
ability to cause disease
pathogenicity
degree of pathogenicity
virulence
characteristic that confers virulence
virulence factor
symbiotic relationship where one organism benefits and the other is harmed
parastitic
individual that is infected
host
something that stimulates immune response (typically associated with microbe)
immunogen (antigen)
protein made by immune system that attaches to microbes to turn on immune responses
antibody
when a pathogen is growing or multiplying in or on a host
infection
when host is not capable of controlling microbial activity
infectious disease
microbial load (can lead to infectious disease)
number of microorganisms
three factors in infectious disease
number of microorganisms; virulence; and host defenses
dose that is lethal
lethal dose
number of microbes needed to cause an infection
infectious dose (ID50)
amount of microbes or dose that kills 50% of hosts
LD 50
streptococcus pneumonia is highly virulent so the LD 50 requires _____ cells then salmonella enterica
less
always cause disease
professional pathogens
cause disease, if given an opportunity
opportunistic pathogens
the oppurtunistic pathogens wait for
a break in barriers, immune system lowered, or compromised host (born with immuno suppression)
strep throat microbe; can colonize oral cavities and opportunistic
streptococcus pyogenes
skin infections microbe; opportunistic; lives on skin but causes disease inside skin
staphylococcus aureus
acne: opportunistic pathogen
proprionibacterium acnes
inflammation comes with
phagocytosis
when microbial load is too high; innate immunity is not enough you need
acquired immunity; specific mechanisms
attacks extra-cellular pathogens; specific mechanisms (in blood and lymph)
humoral response
antibody in humoral response comes from
B-cell
attacks intracellular pathogens; specific mechanisms
cell mediated response
what cells are apart of the cell mediated response (slow; lock and key interaction)
cytotoxic T cells
the typical virus will reside within cells of organism
intracellular pathogens
typical bacterium; reside outside of organisms cell
extracellular
digest foreign particles (innate immunity)
phagocytes
virus or microbe is degraded in _____ (innate immunity)
lysosomes
neutrophil and macrophages phagocytose and make punctured tissue ____
sterile
four major characteristics of inflammation
red, heat, swelling, pain
the macrophage is an ____ ____ cell, it presents bits of captured microbes and presents it to T-cell
antigen-presenting
once the T-cell has been shown microbe by macrophage it can produce
B cells or T cells based off reaction
viruses can release by what two mechanisms
lysis or budding
4 possible outcomes of viral infections
cell death, chronic infection, latent infection or cancer
bacteria dont have tropism but they look for a ____
niche
the more ____ ____ a bacterium has the more it can infect and integrate
virulence factors (survives lo0 nger intracellularly for this reason
DNA segment with virulence gene clusters, have high GC content and are passed between bacteria through horizontal gene transfer
pathogenicity islands
establishment of a microorganism in a particular niche then grow
colonization
micorbes have ____ on end of pili or other proteins
adhesins
adhesins have a small not super specific _____ to recognize specific receptors
tropism
the pilus can use ___ or ____ penetration
passive; active
when pilus uses passive penentration the micorbe is moving _____ damaged barrier
through
when pilus ises active the microbe attaches to extracellular matrix and release enzymes to ____ surface
degrade; allows integration
this adhesin can be attached to membrane and does not need a pilus
afimbrial
the ___ protein has variable domain and resists phagocytosis by changing its variable end proteins (gram -; streptococcus)
M
adhesive structures (3)
teichoic acids, capsules, flagella (non-specific)
induce uptake or actively invade
invasion of host cell
ways that invasion of tissues can happen
lytic enzymes, transcytosis, penetrate deeper tissues (hides here), systemic (enter blood stream)
microbe which induces uptake, releases toxins that cause actin to phagocytose salmonella (manipulates target cell into becoming a phagocyte)
salmonella
how does salmonella manipulate target cell into becoming a phagocyte
polymerization of its actin
pathogen uses forceful entry and releases toxins needed to create a receptor for its own adhesions to attach to
toxoplasma gondii
molecule that alters host cell function
toxins
disease that results from a toxin
intoxication (botulism; tetanus)
endotoxin which induces immune cells to release pyrogens (causes fever) and can cause septic shock
LPS (lipid A)
secreted toxins (exotoxins): 3 categories (they are heat sensitive)
AB toxins, cytolytic, superantigens
the a in the endotoxin is the ____ subunit (moves inside) and the b part in the endotoxin is ____ subunit
enzymatic; binding
two types of AB toxins
diptheria, cholera, anthrax
bind to cholesterol in host cell membranes; form and pore that allows cytoplasmic contents to leak out while toxin goes in
pore-forming toxins (E.coli)
cytolytic toxin tat removes head group from phospholipids
phospholipase
a ____ links macrophages to T cells
superantigen
activate ___% of T cells with superantigen secrete massive amounts of inflammation
25 compared to normal 0.01%
neutralizing antibodies
antitoxin
inactivated toxins that can be used as vaccines
toxoids
gram ___ bacteria use type three secretion
-
where is the type three secretion system typically located
pathogenicity islands or virulence plasmids
the type three secretion system brings and delivers a _____ directly into cytoplasm of host cells
toxins
the type three secretion is triggered by what
host cell contact (such as salmonella)
____ help streptococcus pneumoniae to resist phagocytosis
capsule (make pathogens slippery or it can make pathogen toxic)
mycobacterium tuberculosis and listeria monocytogenes can survive in ____
a phagocyte
when a bacterium is living in a phagocyte the immune system cannot recognize the bacteria; what are three ways they resist being broken down
resist enzymes in lysosomes
prevent formation of lysososome and phagocyte binding
escape vacuole
listeria accumulates ____ in the cell and uses it to propel itself to invade another cell; it is never extracellular
actin
pathogens can kill the ____ to avoid being broken down
phagocyte
pathogens can change the ____; which is alteration of immunogenic structures (gonorrhoeaedoes this with changing its pillus once the immune system recognizes it)
antigen
the pathogens can make proteins that bind ____ and stop it from working
antibody
protein A staph
protein G strep
____ are antibiotic resistant and resistant to immune system
biofilms
a frustrated phagocyte makes a multi nucleated giant cell and releases cytokines on biolfilm; this causes what?
inflammation and overboard immune response
