chapter 15
cluster of differentitation receptors are known by the abbreviated " __ receptors "
CD
proteins protruding from the cell membrane of a variety of cells involved in the immune response are termed __ molecules
CD
how many different types of antigens is a specific receptors can be found on the surface of a given lymphocyte
1
__ are required to present antigen to T cells for activation
APCs
specific immunity
Acquired or adaptive immunity: recognize specific agents, adapt/respond and target these agent
__ is the fragement of the antibody that reveals a region for activating or fixing complement
Fc
__ is the fragment of antibodies that serves as teh effector portion of the molecule as it binds to receptors on the membranes of many different cells
Fc
the variations of amino acid sequences in which antibody fragment give rise to different isotypes (classes) of antibodies?
Fc
this fragment of the antibody molecule is exposed or made more accessible to phagocytes when antibodies opsonize an antigen
Fc
__ cell activation is triggered by binding of antigen to surface IgD molecules
B
Specific immunity is the product of a dual systemcomposed of _ & _ lymphocytes
B & T
teh IRA-B cells are a tpe of __ cell that acts in a __ fashion to alert many components of the immune system to get active
B; NONSPECIFIC
Cytotoxic T cells kill __ cells and __ host cells
foreign infected
an antigen must meet certain requirements in
foreignness,shape or complexity, accessibility, size
clonal expansion of activation B cells results in a large population of __ identical daughter cells
genitically
the enzymes that attack target cells during apoptosis are
granzymes
the more closely related two individuals are the __ the probability is that they will share more MHC class I molecules in common
greater
the cytotoxic IL-2 functions as a __ factor for both T helper and cytotoxic T cells
growth
an __ is a molecule that cannot stimulate a full immune response without being attached to a larger protein molecule called a carrier
hapten
the T cell antigen-specific receptor differs from the B cell antigen receptor in that it
has fewer antigen binding sites
most B cells must interact with T __ cells that bear receptors for epitopes on the same antigen to become functional
helper
since superantigens are potent stimulators of Tcells their presence can result in
huge release of cytokines with deleterious effects cell death
the immunoglobulin __ is found in colostrum and breast milk and forms a protective coating in the gastrointestinal tract of a nursing infant
igA
process of eliminating any lymphocyte with receptors that recognize self molecules during the development process is
immune tolerance
a person displays __ if they have the ability to react to antigen and form a protective immune response even wihtout previous exposure
immunocompetence
B cells recognize antigen using specific B cell receptor which is the __ it will secrete once clonal selection has taken place
immunoglobulin
__ are class of glycoproteins that serve as the antigen-specific receptors on B cells
immunoglobulins
clonal selection and expansion of lymphocytes results in __ immune responsiveness to the specific antigen
increased
the phagocytosis of antigens can induce an __ response in the surrounding tissues if appropriate
inflammatory
T and B cells in the periphery of the body have mechanisms for not reacting to __ __
innocuous antigens
an antibody molecule is made up of 0
two identical light chains and heavy chains
activated T helper cells release a type of cytokines called __ which assist other white blood cells such as B cells in their functions
interleukins
after antigen stimulation T cells fuction in
killing abnormal cells helping other immune cells
mature T cells can constantly travel through the body via the __ and __ systems
lymphatic circulatory
antigens that enter the tissue but not via the blood or mucosa are carried in the __ __ to the lymph nodes
lymphatic fluid
antigens stimulate _____ that have specific receptors for that antigen
lymphocytes
the clonal selection theory states that during stem cell differentiation there are trillions of unique __ created each with its own unique antigen specific receptor
lymphocytes
the clonal selection theory states that during stem cell differentitaion there are trillions of unique __ created each with its own unique antigen-specific receptor
lymphocytes
antigen presenting cells process and present antigenic determinants on their surface and include B-cells and __ and dendritic cells
macrophages
__ B and T cells circulate for long periods of time in order to rapidly respond to same antigen in the future
memory
the __ response to previously seen antigens is basis for the sucess of vaccinations
memory
upon antigen stimulation of lymphocyte multiplication results in the formation of effector cells and __ cells that will persist in circulation indefinetly
memory
upond a primary response to antigen both B and T lymphocytes differentiate into effector cells and also __ cells which rapidly respond upon a secondary exposure to antigen
memory
in blood, IgA circulates in the __ form
monomer
to produce a tremendous repertoire of antigens specific receptors lymphocyte employ
more than 500 gene segment
B cells that have made it through the maturation process have not yet encountered antigen so they are called __ B cells and they enter circulation in order to home in on specific sites
naive
__ cells are probably the first cells to attack cancer cells and virus infected cells since they can act quickly and are not antigen specific
natural killer
antibodies __ viruses or toxins by binding to them and preventing their attachment to host cells
neutralize
after antigen stimulation, B cells produce antibodies to ____ antigen
neutralize inactivate target
following the binding of antigen and receipt of interleukin messages from T help cells, B cell activation signals are sent to the B cell __
nucleus
specfic immunity is highly selective which means that antibodies produced to a specific foreign protein antigen on a virus
only recognize that specific antigen
__ are molecules that coat microbes or other particles enhancing their phagocytosis
opsonins
__ enhances phagocyte recognition by coating the invader with antibodies so that they will be more readily recognized by phagocytes
opsonization
the process of stimulating phagocytosis by affixing molecules such as antibodies and complement, to the surfaces of foreign cells or particles is called
opsonization
IgM is a __ and thus has antigen binding sites
pentamer
upon antigen activation CD8 T cells release __ which are proteins that punch holes in membranes of target cells
perforins
CD8 T cell cytotoxicity involves secretion of
perforins and granzymes
when foreign cells or pathogens first enter a tissue resident __ migrate to the site of antigen entry
phagocytes
T helper 2 cells fucntions to
phagocytose extracellular antigens
Cytotoxicity is the ability for this type of lymphocyte to kill specific target cells
plasma
in antibody-mediated immunity during immune response antibodies are produced and secreted by differtiated B cells called __ cells
plasma
the first time a host encounters a particular antigen an __ specific immune response is generated
primary
for activation T cells require that antigen be ___ and then __ by APCs
processed presented
antigen receptor diversity in lymphocytes is due to:`
random genetic rearrangement events
memory is important to specific immunity in that it allows
rapid mobilization of antigent specific memory lymphocytes
microbes enter the body most frequently through the __ tract or the __ tract
respiratory gastrointestinal
since secretory IgA is found on mucus membranes and secretions it plays an important role in protecting the body from __ pathogens
respiratory genitourinary enteric
an antibody can bind to two of the same epitopes on
same cell or two seperate cells
The rapid rise in antibody titer following a repeat exposure to an antigen that has been recognized from a previous exposure is called an __ immune response
secondary
the anamnestic response is also called a __ immune response
secondary
the specific immune response is highly __ which means that a given antibody B cell receptor or T cell receptor only recognizes a specific antigen
selective
MHC class I proteins allow for recognition of __ molecules
self
a healthy human immune system does not react to __ antigens
self
main function of IgD
serve as a B cell antigen receptor
a given host cell can express
several types of receptors
each indiviual mature B and T cell has the capacity to respond to
single unique antigen
host cell surface proteins are involved in __ and thus guide specific immune responses
specific immune recognition
during lymphocyte __ cell different Tatian random gene rearrangement occurred that result in the generation of a large array of antigen receptor diversity
stem
random gene rearrangement forgeneration of antigen specific receptors on lymphocytes occurs durin
stem cell differentation
__ such as some bacterial toxins are potent stimulators of T cells and are responsible for diseases such as toxic shock
superantigens
human MHC genes also known as
HLA
CD8 cells recognize antigen bound to MHC class __ molecules
I
__ binds via its __ fragment to receptors on mast cells and basophils, causing the cells to release potent inflammatory substances upon the binding of allergen
IgE Fc
__ is the most prevalent antibody in cirulation and tissue fluids
IgG
__ is the only antibody capable of crossing the placenta
IgG
classes of antibodies found in humans are
IgG IgD IgA IgM IgE
early in the primary immune response most antibodies are of which class?
IgM
the first antibody produced by the body following exposure (first encounter) to a specific antigen is __
IgM
steps in generating diversity in B cells
One in the bone marrow stem cells become lymphocytes two sells build their unique immuno globin receptor three cells migrate to secondary lymphoid tissues
__ classes of MHC genes have been identified
three
T cell maturation is directed by
thymus glands and hormones
the __ components help move IgA across mucous membrane
Secretory
__ CELLS DIRECT THE RESPONSES THAT TAKE PLACE MEDIATED IMMUNITY
T
__ cells in lymphoid organs are primed to react with presented antigens
T
cell mediated immunity based n the activation of __ cells
T
__ when activated can help activate B cells
T helper cells
teh CD4 coreceptor is found on the surface of what cell type?
T helper cells
a measure of antibody level in a patients serum is called
titer
cytotoxic T cells can destroy:
Virally infected cells Cancer cells Cells from other animals and humans
the __ regions found on both the heavy and light chains in an antibody molecule come together to form the antigen binding site
variable
the antigen binding fragment of an immunoglobin molecule consisting of a combination of heavy and light chains whose molecular conformation is specific for the antigen called
variable region
antigens are usually
a protein or large polysaccharide
__is the aggregation formed by antibodies binding cellular antigens or large particles
agglutinate
an antigen that provokes an allergic rxn is
allergen
IgE is in low concentration in the blood except during
allergies or parasitic infections
an __ is an antigen that is present in some but not all members of a species
alloantigen
a plasma cell is the progeny of an activated B cell that actively produces and secretes
antibodies
during the primary immune response a latent period occurs at the beginning of the response and it is marked by a lack of __ to the activating antigen
antibodies
following stimulation by antigen B cells differentiate into plasma cells which produce and secrete __ and cells which will react rapidly if the antigen is encountered at some point in the future
antibodies memory
Any exposed or released protein or polysaccharide is a potential ______ , a molecule capable of eliciting a specific immune response.
antigen
Each different antibody differs in its __ binding groove
antigen
each different antibody differs in its __ binding groove
antigen
the Y shaped antibody structure, the __ binding sites are foudn at the ends of the arms or the Fab fragments
antigen
the principal activity of an antibody is to unite with, immobilize, call attention to or neutralize the __ which is complementary to its receptor
antigen
__ presenting cells are involved in the activation of T helper cells through the displaying of immunogen fragments on their MHC __ molecules
antigen II
a molecule that stimulates a specific response by T and B cells are called __ or __
antigen immunogen
in most specific immune responses antigen must be processed and presented by _ _ cells
antigen presenting
because human all differ genetically proteins from one person can be __in another person
antigenic
the property of behaving as an antigen binding specifically to a T or B cell receptor is called
antigenicity
__ are foreign molecules that elicit a specific immune response
antigens
an antibody that can neutralize a toxin can also be referred to as
antitoxin
when comparing the T and B cell antigen-specific receptors they both
are formed by genetic rearrangements are inserted into the lymphocyte cell membrane belong to same protein family
during development B and T lymphocytes arise from
at same basic stem cell
the loss of immune tolerance can lead to a disease condition called
autoimmunity
B-cell maturation occurs:
bone marrow
antigens that enter the body intravenously do NOT become localized in the
brain
the constant regions of antibodies usually have varying amounts of
carbohydrates
when a hapten molecule is bound to an __ molecule the resultant complex will allow the hapten to stimulate an immune response
carrier
the effect of binding an antibodys Fc fragment to an Fc receptor on a cell depends on
cells role
the multiplication of lymphocytes upon encountering antigens results in production of a __ or group of genetically identical cells
clone
the clear yellow early product of breat milk that is very high in secretory antibodies is
colostrum
Binding of antibody to antigen can activate the _ cascade which can result in cell or virus lysis
complement
the __ Cascade is a series of proteins in circulation that become secretly activated after the first component is activated by immune complexes cells or virus bounded by anti-body leading to the lysis of a cell or virus
complement
the __ cascade is a series of proteins in circulation that becomes sequentially activated after the first cmponent is activated by immune complexes (cells or virus bound by antibody) leading to the lysis of the cell or virus
complement
MHC III genes encode proteins that are involved in the
complement system
antigen and antibody must have an __ fit
complementary
the __ region of an antibody usually has carbohydrate molecule attached to it
constant
after maturation B and T cells
constantly recirculate through blood and lymphatics
mast cells and basophils have receptors that bind to the Fc fragment of IgE and upon allergen binding by the surface bound IgE the cell releases __ nand allergic mediators such as histamine that increases the allergic response
cytokines
the CD8 coreceptor is expressed on __ T cells
cytotoxic
what cell type destroys cells from other animals and humans based on the peptides they display on their surface with MHC class I?
cytotoxic T
antigen activated T cells give rise to
cytotoxic T cells T regulatory cells T helper cells
upon entry of foreign cells or pathogens into tissue phagocytic cells called __ cells ingest the intruder and then migrate to the nearest lymphoid organ to present antigen to T lymphocytes
dendritic
__ engulf antigen and modify it so that it will be more immunogenic and recognizable to T lymphocytes
dendritic cells
three main antigen presenting cells
dendritic cells, B cells Macrophages
when antibodies attach to their specific antigen, the antigen is marked for __ or __
destruction or neutralization
T and B cells undergo the development and maturation process in
different tissues
the size and amino acid composition of an antibodys Fc fragment determines an antibodys
distributio in the body class or isotyoe permeabilty
the four polypeptide chains that make up an antibody molecule are held together by __ bonds
disulfide
T helper 2 cells functions
drive B cell proliferation, secrete cyokines
antigens possess determinant groups called ____ that are recognized by lymphocyte antigen specific receptors
epitope
the precise molecular group of an antigen that defines its specificity and triggers an immune response is called a __
epitope
an important characteristic of an antigen is that it be perceived to be
foreign