Immunology Flashcards
what are three ways the body is protected from threats
- barriers (skin, mucous membranes)
- Inflammation
- Immunity
T/F many inflammation mechanisms are unique to only inflammatory processes
false, inflammatory processes are common in immune responses
inflammation
the cellular and chemical reaction to injury
what are five causes of inflammation
- microbial infection
- physical agents (trauma, radiation)
- chemical irritation
- hypersensitivity reactions
- necrosis
what are the four clinical features of inflammation
- heat (calor)
- redness (rugor)
- swelling (tumor)
- pain (dolor)
T/F inflammtion often causes a loss of function which can be a component in disease processes
true
what are four histological features of inflammation
- vasodilation
- increased vascular permeability
- formation of fluid exudate
- pus
what are four benefits of inflammation
- dilution of toxins
- entrapment of microbes
- increased blood supply
- spread of cytokines to enhance immune response
what are three negative consequences of inflammation
- cell destruction releases lysozyme
- loss of function due to edema
- possible acceleration of chronic process
what are the four possible outcomes of inflammation
- resolution
- suppuration
- organization (scar formation)
- chronic inflammation
what is an example of an infection that leads to chronic inflammation? why?
tuberculosis
because the mycobacterium are too large to phagocytized and are walled off instead
T/F in most cases the causative agent does more damage than the inflammatory process
false, inflammation commonly is more destructive
what are the two divisions of the immune system
- adaptive
- innate
what are two main tasks of the immune system
- ward off foreign cells
- eliminate abnormal self cells
which of the divisions has a faster response
innate
which of the divisions of the immune system is more specific
adaptive
which division of the immune system has the potential to cause more harm to the patient
adaptive
what two parts are the adaptive and innate immune systems divided into
humoral and cellular
what are the cells used in cellular innate immunity
- macrophages/monocytes
- neutrophils
- NK cells
what is the difference between macrophages and monocytes
monocytes are free moving macrophages are in tissue
what are the divisions of leukocytes
granulocytes and agranulocytes
what types of leukocytes are granulocytes
basophils, eosinophils, neutrophils
what are two agranulocytes
lymphocytes and monocytes
what are the leukocytes from the myeloid line? lymphoid line?
monocyte, neurophil, basophil, eosinophil
T and B lymphocytes
is the differentiation between myelocytic or lymphcytic cells clinically relevant
yes, leukemia can be described as myelocytic or lymphocytic
what are the most numerous leukoctye? what percent?
neutrolphils, 70%
what is the neutrophils mode of action
phagocytosis
what is the stimulating and attracting compound for neutrophils
cytokines
what is the effect of cytokines on neutrophils
increase in phagocytosis and diapedisis
cytokine
a small protein or polypeptide used to modulate immune response
what are three common cytokines
- tumor necrosis factor alpha
- interleukins
- interferon
what are the three phases of a macrophage
- resting
- activated
- hyperactivated
what is the function of a macrophage in an activated state
phagocytosis and antigen presenting cell
what is the stimuli that will push an activated macrophage into a hyperactive state
mannose, lipopolysaccharide (bacterial cell carbohydrates)
what is the effect of hyperactivation on a macrophage
increased phagocytosis and secretion of cytokines
what type of cell is lymphocyte
lymphocyte
what is the function of NK cells (such as?)
the destruction of abnormal cells (tumor cells, viral infected cells, cells tagged with antibodies)
what is the humoral component of the innate immune system
complement
compliment proteins
a group of 20-30 plasma proteins that function as proteases
what is the result of compliment activation
a cascade that forms a membrane attack complex
T/F a mutation in one gene can produce a defect in the compliment cascade that will result in chronic infections
true
what are the three pathways of compliment activation
- classical
- alternate
- mannan lectin activation
what activates the classical compliment pathway?
antigen-antibody complexes
what activates the alternate compliment pathway
lipoproteins and glyocproteins on microbial surfaces
what activates the mannan lectin compliment pathway
microbial carbhydrates
what are three primary actions of the complement system
- direct attack on microbes
- opsonization of microbes
- chemoattractant for phages
what are four indirect actions of complement proteins
- augements production of antibodies
- increases production of memory cells
- disposal of antigen-antibody complexes
- disposal of apoptotic cells without inflammation
opsonization
the process by which chemicals or antibodies bind to a target increase its chances of being phagocytized
what is the common thread linking all innate responses
the all involve responses to molecules commonly found on microbes (PAMPs)
what is a PAMP? what do they allow for
pathogen associated molecular patterns
the concept that most microorganisms have repeating molecular structures that trigger innate immune responses
DAMPs
damage associated molecular patterns
endogeneous molecules that are released from damaged cells
PRRs
pattern recognition receptors
innate immune mechanisms that recognize PAMPs and DAMPs to trigger a faster response
what are the two components of the adaptive immune system
cellular and humoral
why do we need an adaptive immune system
- longer life spans mean more exposure to pathogens and neoplasia
- larger organisms have more opportunities for infection
- slow reproduction means longevity is vital to the species
what part of the adaptive immune system consist of antibodies
the humoral component
immunoglobulins (antibodies)
circulating proteins that bind to antigens
what the 5 types of antibodies
- IgG
- IgM
- IgA
- IgE
- IgD
of the five antibodies, which doesn;t have a well defined immune function
IgD
what is the function of IgG
A longer immune response and long lasting immunity
what is the function of IgM
a fast, nonspecific reponse to antigens
where is IgA found
secretions (spit, mucous, breast milk, tears)
when is IgE normally produced by the body
during allergic reactions and parasitic disease
why are antibodies sometimes called gamma globulins
because they can be extracted from plasma in the “gamma” fraction
antigen
anything that triggers an immune response, acts a ligand for antibodies
where do antigens bind to antibodies? what does this allow for
the variable end
it allow for antibodies to bind with many types of antigens
T/F all antibodies pass the placenta
false, IgG, E, and A can pass, IgM is too big
what is the most common function of antibodies
tagging abnormal molcules for later removal or destructrion
what is a neutralizing antibody
an antibody that binds to the receptor on a pathogen so that it is rendered non-functional
Bnabs
broadly neutralizing antibodies
how are Bnabs developed? why are the important?
developed over time in response to repeated infections
target important antigens and possibly treatment of rapidly mutating pathogens
what is the most common antibody? how long does it take to produce
IgG, 7-14 days
Why do people need immunization boosters
because over time your without exposure your IgG levels wane
what cells does IgE bind to during allergic responses
mast cells
what is indicated if
IgG levels are high, IgM is zero?
IgG is zero, IgM is high?
There is long term immunity still present to fight off the infection
there is a disease active present for which there is no long lasting immunity
what are the two cells of the adaptive immune system
T and B cells
What is the role of the thymus in T cell production
it matures new T cells and teaches them differentiation of self
what is the function of T cells
recognition and destruction of intracellular pathogens and abnormal cells
what is the function of B cells
recognition of extracellular pathogens or surface antigens and the production of antibodies
how many antigen receptors are present on a B cell? what happens when it is bound?
only one
the cell will become a plasma cell or memory cell
plasma cells
B cells that produce antibodies and can function as an antigen presenting cell
Memory B cells
cells that clone themselves when exposed to an antigen to produce more plasma cells
what are three significant histological features of a plasma cell
- displaced nucleus
- lots of cytoplasm
- large ER
what are the three types of T cells that we will study
- Helper T
- Killer T
- Memory T
what ae the CD designations of helper T and killer T cells? what does that refer too?
Helper T is CD4
Killer T is CD8
specific sites on the celll surface
what type of T cell does HIV attack
CD4 cells
what are the functions of a CD4 cell
- assist in the activation of B cells
- assist in the activation of killer T cells
- secretion of cytokines (complement)
How do CD8 cells react to antigens
- drilling a hole in a cell membrane with perforin and injecting granzyme
- Triggering apoptosis by binding to the Fas ligand
what are the three APCs
- dendritic cells
- activated macrophages
- activated plasma cells
what are dendritic cells
monocytes found in tissue that constantly sample the environment for antigens and present the pieces of the antigens to T and B cells
what is the process of activation in the adaptive immune system
- APCs recognize and process antigens
- taxsis into the lymph tissue
- presentation of antigens to T and B cells
How are immune cells able to recognize self cells
the major histocompatibility complex, which in the case of humans is called the human leukocyte antigen complex
what chromosome creates the MHC
chromosome 6
why is the MHC gene important for organ transplant
it determines how closely the transplanted organ will match the host
what is an example of a cell that doesn;t have HLA
red blood cells because they have no nucleus
what are two types of HLA and where are they normally found
HLA I and II
HLA I is found on all nucleated cells
HLA II is the antigen presenting complex found on APCs
what does it mean to say T and B cells are self tolerant
T cells dont attack normal cell and B cellls don’t produce antibodies to self antigens
what is the two test process for training T cells
select cells that can recognize self so they can interact with APCs
eliminate cells that react strongly to self
what percent of T cells pass the two test process
1-3%
If the majority of T cells that react to self are eliminated, how can T cells produce autoimmune disease
because not every self antigen can be test for, and some reactive T cells escape
how do B cells learn self tolerance
they are tested in the bone marrow for reaction to self antigens, if they fail and can’t remodulate their B cell receptor they are eliminated
