Immunology Final Exam
how long does B-cell maturation from an HSC to a mature B cell take?
1 to 2 weeks
the percentage of developing T cells that survive positive selection is approximately
2%
SHM and CSR are both dependent on the activity of which of the following enzymes?
AID
which of the following do you expect would be actively functioning in a B cell that had migrated to a germinal center?
AID
which cell type can activate a memory T cell?
B cell; dendritic cell; macrophage
what does CD45R+ cells represent?
B cells
all of the following are true regarding B-cell development except
B cells, like T cells, are MHC class restricted
the receptor for CTLA-4 on APCs is ________. when CTLA-4 on a newly activated T cell (not a regulatory T cell) binds to its receptor on APCs, the T cell _______.
B7-1 (CD80) or B7-2 (CD86); stops proliferating
which of the following constitutes the critical survival cytokine for B cells in the secondary lymphoid tissue cortex?
BAFF
which of the following is required for T2 B cells to become mature B cells?
BAFF
which of the following can be directly activated as a soluble protein in the microenvironement surrounding a pathogenic cell?
C3
which of the following can be directly activated s a soluble protein in the microenvironment surrounding a pathogenic cell?
C3
Of the molecules listed, which can be considered the key molecule in complement pathways?
C5 convertase
which of the following is the most potent anaphylatoxin produced during the complement cascade?
C5a
which of the following molecules provide costimulatory signals to naive T cells?
CD28
which of the following does not induce apoptosis of the target?
CD28 on CTL binding to B7 on target cell
which of the following molecules would double-negative T cells fail to express?
CD4
what is currently the best explanation for what determines whether a T cell develops into a CCD8+ T cell or CD4+ T cell?
CD4 or CD8 expression is determined by the strength and duration of the TCR/MHC interaction
which factors onto surfaces of B cells and T cells, through their interaction, are required to allow germinal center formation to occur?
CD40 and CD40L
activated Th cells signal to B cells to initiate their activation program via which of the following?
CD40L on the T cell to CD40 on the B cell
match the molecule with the region of the cell it is used to label:
CFSE- plasma membrane PKH67 dye- used to determine if a gene is being transcribed PCR- used to determine if a gene is present in a chromosome
which molecule is most closely associated with inhibitory responses to antigen?
CTLA-4
match the treatment with the correct molecule
CTLA-4 agonist- would likely decrease activity of alloreactive T cells CD28 agonist- would likely increase activity of allorective T cells
CTLA-4 is a costimulatory receptor on T cells that belongs to the same family as the CD28 costimulatory receptor. however, CTLA-4 is antagonistic to CD28. which of the following could be a functional advantage of CTLA-4 expression within the immune response?
CTLA-4 limits the immune response of Tc and Th cells after an infection has been cleared.
match the number with the correct description
Cell A- dendritic cell Cell B- activated T cell molecule 2- CRACC molecule 4- CD28
if CD4 needed to be added to the image, CD4 would be drawn on _____ and the cell would be a ______.
Cell A; helper T cell
(Bates) the research suggests that _____ ______ the inflammation that occurs during _____.
DHA; inhibits; SLE
which of the following represents the earliest stage in T cell development
DN
receptors that bind the constant regions of antibodies are known as
Fc receptors
you have consumed a salad contaminated with Salmonella enteric, which typically causes a self-limiting, gastrointestinal disease in humans. based on this information, which immune organ is most likely to first recognize and mount a response against the pathogen?
GALT
which of the following is the pluripotent stem cell that gives rise to all blood cells?
HSC
bonds formed between the T cell and a dendritic cell are relatively weak. which of the following help to strengthen this association so that a T cell can see which antigen is being presented by a dendritic cell?
ICAM-1/LFA-1
(McLamb) you are a new member of the lab and you'd like to perform additional experiment to test the effect stress has on the inflammation. what is the measurement that could be obtained in the future experiments that you would expect the level to increase in early wean pigs? which technique would you use?
IFN-beta; sandwich ELISA
which of the following is not usually induced in response to TLR signaling?
IL-4
(Bates) you are a new member of the lab and you'd like to perform additional experiments to test the effect of DHA has on SLE. what is the measurement that could be obtained in the future experiments that you would expect the level to decrease in SLE patient treated with DHA?
IL-6
this picture represents general components of cell signaling pathways associated with transmembrane receptors. based on what you learned about CRACC, match the proteins/regions below with the correct description.
ITSM motifs- if arrow 1 is pointing to CRACC the protein that arrow 2 is pointing to represents SH2 domain- the regions represented by the red star in protein 2 is Box 4- the enzyme SHIP would most likely inhibit the process indicated by EAT-2- if box 1 is pointing to the CRACC molecule what is the name of the regions represented by the yellow bars?
choose the most likely y-axis label for the graph below is group A represents patients who lack poly Ig receptor and group B represents patients who express the poly Ig receptor
IgA in mucus
mature naive B cells express high levels of ____ on their cell surfaces
IgD
mature naive B cells express high levels of _____ on their cell surfaces.
IgD
deficiency in CD40L on T cells can cause immunodeficiency, resulting in decreased numbers of circulating _____
IgE
some of the cytokines secreted by Th2 cells signal B cells to produce __________ which helps in the destruction of parasites.
IgE
if a patient has low levels of IL-4, or an absence of IL-4, what antibody isotope would most likely decrease?
IgG/IgE
which of the following is capable of undergoing successive rearrangements to prevent the formation of auto reactive lymphocyte receptors?
IgLk
which of the following immunoglobulin isotope is the most efficient at initiating a complement fixation cascade?
IgM
which of the following immunoglobulin isotopes is the most efficient at initiating a complement fixation cascade?
IgM
why is IgM able to form large polymers?
IgM has low affinity and benefits from having a large number of binding sites
considering the effects of EEP reported int eh research article, which of the following would be least likely y-axis label for this graph?
IkB bound to NFkB
(McLamb) the measurement that was not taken in the study was
Il-1
if a host cell has the ligand for _____, then the host cell is less likely to be killed by a NK cell
KIR2DL1
when either self or foreign proteins are digested by the proteasome, the peptides produced from those proteins are more likely to be presented on
MHC I molecules
the TCRs on the surface of the T cell, which are identical (usually), determine the antigen specifically of an individual T cell. thus, to detect antigen-specific T cells, you need a molecule that will bind to the TCR. to detect an influenza specific CD8+ T cell, you would therefore need
MHC I molecules containing influenza peptides
which of the following treatments would most likely inhibit activation of CD4+ T cells and have little/no effect on CD8+ T cells?
MHC II antagonist
CD4+ t cells recognize
MHC class II peptides
Which of the following adapter proteins activate the NKkB pathway?
MyD88
(Sittisart) you are a new member of the lab and and you'd like to perform additional experiment to test the effect of EEP. Based on the knowledge you have about Eep, what measurement would give you the following graph?
NFkB in nucleus
human cells lining the upper respiratory tract are expressing abnormal levels of surface MHC proteins due to a developing viral infection. which cell type listed below is most likely to recognize the cells as infected based on altered MHC levels?
NK cells
how can receptors of the innate immune system, such as PRRs, be considered both specific and general?
PRRs recognize molecules shared by groups of pathogens, not those unique to a species or strain. for example, many bacterial pathogens contain flagella, which would all be recognized by TLR5. however, bacterial pathogens lacking flagella will not be recognized by TLR5.
which of the following is the correct relationship? ____ on ____ recognize _____ on _______.
PRRs; macrophages; PAMPs; pathogens
which enzyme is required to initiate process of VDJ recombination?
RAG
which of the following DNA/protein complexes would you expect to find in a cell undergoing receptor editing?
RAG/VJ
what would be the most accurate y-axis label for the graph shown if group B represented double-negative thymocytes and group A represented double positive thymocytes?
RAG/VJ copmlex
how does allelic exclusion prevent multiple heavy-chain rearrangements from occurring in pre-B cell?
RAG1 and RAG2 are down regulated, and TdT activity is lost so that no additional heavy chain rearrangements may take place
how does allelic exclusion prevent multiple heavy-chain rearrangements from occurring in pre-B cells?
RAG1 and RAG2 are down regulated, and TdT activity is lost so that no additional heavy-cain rearrangements may take place
what introduces single-strand between V(D)J coding sequence and heptameter RSS?
RAG1/2
what recognizes nonuser RSS to begin lymphocyte receptor rearrangement?
RAG1/2
what does the RAG 1/2 enzyme complex bind to at the start of the V(D)J recombination process?
RSS
different effector functions of antibodies depend on the isotope of antibodies and the receptor they bind to. which of the receptor-ligand interaction is correct?
RcRn-IgG
which of the following cell types are lymphocytes?
T cell
of the cells listed below, which one represents the most developed B cell?
T2 B cells
a number of stains of the bacteria Salmonella enteric contain flagella and can invade human cells. based on figure 4-6, which TLRs are most likely to be used to recognize such strains?
TLR5 and TLR9
which enzyme adds new nucleotides to chromosome that are not present in germline DNA sequence?
TdT
what would be the most accurate y-axis label for the graph shown if group A represented pre-B cells and group B represented pre-B cells?
TdT/VDJ complex
choose the most likely y-axis label for the graph below. Group A (low) represents pro-B cells and group B (high) represents pre-B cell?
TdT/VJ activity
interferon-gamma is secreted by ____ and activates ____.
Th1 cells; macrophages to phagocytose
I heavy chain genes, what are the gene segments?
V, D, J
which of the following cell types is least likely to be killed by a NK cell?
a bacterial cell
the top picture most likely represents a chromosome in
a cell that lack RAG enzyme
which of the following cells is most likely to survive selection int he thymus?
a cell with a TCR that has low affinity for the peptide/MHC complexes in the thymus
which of the following would you predict to result in decreased susceptibility to septic shock?
a mutation in TLR4
LPS tolerance is not characterized by
a positive feedback loop
considering how C3 and C5 are activated, which of the following treatments would most likely inhibit their activation?
a protease inhibitor
an electrophoretic mobility shift assay determines if
a protein is able to bind to a specific nucleotide sequence
which of the following correctly describes an ELISA? all correct answers must be selected to receive full credit.
a standar curve can be used to determine concentrations of a molecule in a sample, providing quantitative data; uses antibodies with enzymes attached; uses antibodies to bind to a specific target
the pathogen used to infect the pigs was
a strain of E coli that has a toxin that causes diarrhea and is a major cause of sickness and death in children worldwide
in negative selection, cells that receive _____ signal through their antigen receptors die.
a strong
which of the following is not an effector function of antibodies?
activation of cytotoxic T cells
the fas ligand (FasL) represents a key signaling pathway among cell mediated effector cells. what is the function of the Fas-FasL signaling pathway?
activation of the Fas-FasL signaling pathway triggers apoptosis
what is the best description of the following data?
active transcription of TNF
C-reactive protein is a(n)
acute phase response protein
if a human were unable to produce lymphoid progenitor cells, predict which part of the immune system would be most greatly impacted?
adaptive immunity
several proteins must work in a coordinating fashion to achieve V(D)J recombination. which of the following is the function of TdT
add non-templated nucleotides to the V-D and D-J joints of Ig heavy chains
which of the following are associated with damaged or dead cells?
all of these: low CD47; altered carbohydrates; cell surface annexing I; lysophosphatidic acid
which of the following complement fixation pathways can be initiated by a soluble C3 converts?
alternative
regarding Myasthenia Gravis, which of the following statements is true?
an antagonistic IgG antibody is binding to the ACh receptor blocking it for stimulation, leading to paralysis
what is the effector molecule of humoral immunity?
antibodies
which of the following is not entirely a response of the innate immune system?
antibody mediated complement activation
virally infected host cells are tagged with antigen-antibody complexes. these complexes recruit NK cells that trigger apoptosis in the infected host cell. this is an example of
antibody-dependent cell mediated cytotoxicity
what is the component of immune complexes?
antigen + IgG
which most likely accurately represents the general order of the steps to antigen presentation?
antigen acquisition, antigen breakdown into peptides, encounter of peptides with MHC molecules, binding of peptides to MHC molecules, and display of the peptide-loaded MHC molecules on the cell surface
BALF would most likely be collected if you were studying
asthma
in cytokine activated cells, STAT proteins are more likely to
be bound to DNA; form dimers
why are many opsonins multimeric?
because they bind repeating structures on pathogen surfaces
which of the following would not be included when examine a person's exposome?
being born with a p53 mutation
the CTLA-4 expressed by tregs is used to
bind to costimulatory molecules on dendritic cells and block costimulation of naive T cells
B lymphocytes are made in the
bone marrow
all blood cell in an adult human can trace their ancestry to which compartment within the body?
bone marrow
all blood cells in an adult human can trace their ancestry to which compartment within the body?
bone marrow
committed lymphocyte progenitors originate in the
bone marrow
where fo B and T lymphocytes originate?
bone marrow
where is the least likely location of a follicle?
bone marrow
which of the following is the correct pathway for B cell development, activation, and differentiation?
bone marrow -> spleen -> GC -> bone marrow
V-J rearrangement occurs in
both B and T cells
deficiency in RAG1 and/or RAG2 can affect the proper development of which of the following cell types, resulting in deceased numbers of circulating cells of those types?
both B and T cells
deficiency in RAG1 and/or RAG2 can affect the proper development of which of the following cell types, resulting in decreased umbers of circulating cells of those types?
both B and T cells
which of the following is required to Tell activation?
both antigen-specific TCR binding to MHC peptide and interaction with CD80, CD86, or ICOS-L are correct
ELISPOT assays
both involve the use of capture antibodies and are used to detect individual cells
peptide binding diversity is increased by
both multiple MHC alleles in the population and multiple homologous MHC genes in the genome
how do natural killer cells kill their targets?
by inducing apoptosis
in the research described int eh article by Sittisart et al., which of the following serves as a positive control?
cells treated with LPS
which of the following processes does not require DNA recombination?
changing the variable region of activated, mature B cells
which of the following complement fixation pathways can be indirectly initiated by a B cell?
classical
immature B cells int eh bone marrow that are found to bear self-antigen reactive BCRs undergo which of the following?
clonal deletions light chain receptor editing; and development of anergy
what characterizes the pro-B-cell stage in B-cell development?
commitment to the B-cell lineage
all of the following are functions of Th1 cells except
contribute to autoimmunity
CD8+ T cells exposed to MHC class I peptides are
cytotoxic T cells
IL-10 has the opposite effect of TNF, if cells are treated with IL-10, the most likely effect would be a/an
decrease in nuclear NF-kB
compared to cells treated with TNF, if cells are treated with IL-10, the most likely effect would be a/an
decrease in nuclear NF-kB
multiple negative feedback mechanisms were discussed int he textbook to control inflammation. which of the following mechanisms are not used to control inflammation?
decreased production of IkB
which of the following would you predict to result from a mutation in TLR4 that prevents binding to LPS?
decreased susceptibility to septic shock
Th17 cells are involved with all of the following except
delayed-type hypersensitivity
which of the following is most likely to stimulate a memory T cell?
dendritic cell; memory cell; B cell
of you wanted to measure the level of CRP in a sample, you would use
direct (sandwich) ELISA
which of the following best describes the differences between types II and III hypersensitivity reactions?
direct recognition of cell-surface antigens by antibodies in type II reactions versus deposition of improperly cleared antibody-antigen complexes in type III reactions
M cells are specialized
epithelial cells that transport antigens for the lumen of the intestines to leukocytes within the gut lymphoid tissue
what characterizes the pre-B-cell stage in B-cell development?
expression of the pre-BCR; rearrangement of light chain genes; proliferation; both expression fo the pre-BCR and proliferation
heavy chain polypeptides are either called kappa or lambda chains.
false
true or false: the innate immune responses work largely independently of one another.
false
(Bates) int eh research paper discussed in class, which of the following was considered to be anti-inflammatory?
fish oil
Mature T cells are similar to mature B cells since mature T cells
have TCR genes that were produced by random rearrangement of gene segments
if mice lacked CTLA-4, what would you expect to find in the mice?
high levels of T cells
choose the most likely label for the graph below. group A (low) represents a test tube with mast cells that lack FceR and group B (high) represents a test tube with mast cells that express FCeR. assume IgE binding to antigen have been added to the test tubes
histamine
CTLs. mediate a powerful and lethal immune response to infected host cells. which of the following steps is not involved with CTL activation and function?
histamine is released from cytoplasmic granules, recruiting macrophages to the site of infection
Fab
if an antibody was attached to a virus, this region would be specifically binding to the virus; this region is always different between IgG and IgE; this region contains the variable regions of the heavy and light chains
this type of cell will leave the bone marrow and complete maturation in the spleen.
immature B cell
where would you most likely find a TLR that recognizes viral DNA?
in the end-some/lyosome
where would you most likely find a TLR that recognizes RNA?
in the endosome/lysosome
which of the following is not an effect of C3a and C5a binding their receptors on leukocytes?
increased vascular permeability via induction of TNF and IL6 secretion; induction of degranulation by granulocytes; and increased smooth muscle contraction to aid in delivering immune cells and molecules to the site of infection
the function fo SHM is best described by which of the following statements?
increasing the affinity of immunoglobulins for their antigen
in order to measure regulatory R cells, FoxP3+ cells are often measured. FoxP3 functions by
increasing transcription of anti-inflammatory genes
which of the following statements best differentiates innate and adaptive immune responses are not required.
innate responses are stronger during the primary and less important during the secondary response, whereas adaptive responses are less robust during primary responses and stronger during secondary responses
the difference between an ELISA and an ELISpot is that only one of the assays (not both assays)
involves adding cells to a well
what defines an exogenous antigen?
it is generated outside of the cell then taken into the cell by endocytosis
what defines an endogenous antigen?
it is generated within the cell
NK cells are more likely to be activated by a cell line that
lacks MHC class I molecules
at what stage of development does a B cell begin to express a pre-B-cell receptor?
late pre-B cell
what is the final step of the V(D)J recombination process?
ligation by DNA ligase IV and NHEJ proteins
the samples used in the Sittisart study was
macrophages
of the cells listed below, which one represents the most developed B cell?
mature B cells
memory T cells, effector T cells, and naive T cells share several characteristics. which of the following description could only be said of memory T cells?
memory T cells are activated by an APC
a bacterial pathogen has breached the skin barrier of a human. this is the first time this human host has been exposed to this particular pathogen. which statement is not true regarding the situation?
memory T cells will aid in pathogen recognition and response
which of the following is considered negative control in the research we discussed in class?
mice prone to lupus
the research described in the article by Melissa Bates et al., was performed using
mice that spontaneously develop lupus like symptoms over time
choose the most likely y-axis label for the graph below is group A represents the test tube with cells that express FcRn and group B represents a test tube with cells that lack FcRn. assume both IgG and IgA have been added to the test tubes containing the cells.
monomeric IgG in the supernatant
when performing an ELISA, if the OD measurement is higher in a sample, that sample contains:
more detecting antibodies attached to antigens compared to other samples
which of the following IgH chains is not produced as a result of CSR?
mu
the first immunoglobulin isotope produced during the course of a primary immune response contains which of the following heavy chains?
mu (u)
which lineage of immune cells constitutes the first line of defense against an infection?
myeloid
which cell can differentiate into the greatest variety of cells during hematopoiesis?
myeloid progenitor
what term best describes a selection process against those cells whose T cell receptors bind too strongly to self-peptide/MHC combinations?
negative selection
________ describes the action of antibodies whereby antibodies bind to a pathogen and prevent the pathogen form interacting with cell receptors.
neutralization
when the skin becomes inflamed, which of the following occurs?
neutrophils move from the blood into the interstitium
which of the following best explains the timing of the classical pathway of complement fixation, relative to the other pathways of complement fixation, against a pathogen in an individual who has never been exposed to said pathogen?
no target for C1 exits on the surface of the pathogen in the earliest stages of the response to it
in flow cytometry, in addition to fluorescent markers, forward (FSC) and side (SSC) scatter are measured, and
none of the answers are correct
C-reactive protein is a(n)
opsonin
_______ describes the recruitment of phagocytic cells by the Fab portion of an antibody.
opsonization
(McLamb) which group of pigs would be classified as living in the environment with the highest stress?
pigs weaned at 16 days of age and infected with a pathogen
which group of pigs would be classified as living in the environment with the highest stress?
pigs weaned at 16 days of age and then infected with a pathogen
V-J recombination occurs during which phase of a B cell's development?
pre-B cell
at what stage of development does a B cell begin to express a B-cell receptor with surrogate light chains?
pre-B cell
which of the following is used to generate diversity in the antibody repertoire?
presence of multiple variable gene segments that can be assembled in multiple different combinations; addition of N nucleotides that are not encoded in the germ line; exonuclease trimming of excess nucleotides at variable segment junctions; ability to pair a single heavy chain with different light chains, so as to avoid generation of auto reactive antibodies
a positive feedback loop would be useful in all of these scenarios except
preventing an overreaction to a stimulus
what is the function of bone marrow stroll cells with respect to B-cell development?
prevents self-antigens to B cells for negative selection
V-DJ recombination occurs during which phase of a B cell's development?
pro-B cell
what characterizes the pre B cell stage in B cell development?
proliferation; expression of the pre BCR; both expression fo the pre-BCR and proliferation; rearrangement of light chain genes
CFSE is used to measure ________ of cells. this process is occurring __________ in cells as the levels of CFSE decrease.
proliferation; more
which of the following defenses is most likely to protect a plant form a microbial pathogen?
reactive-oxygen species
which of the following accounts for allelic exclusion in rearrangement within the IgH locus?
rearrangements only occurs on one homolog at a time, and once one homolog has successfully rearranged, the other is methylated to produce heterochromatin
in an inflammasome has formed in a cell, the cell is most likely
secreting interleukin 1 (IL-1)
which of the following best describes chemokines?
soluble proteins that recruit specific cells to an area
where do developing B cells complete their maturation through the T1 and T2 stages?
spleen
what types of cells are good targets for natural killer cells and why?
stressed self cell because they have altered class I MHC
signaling through the pre-TCR occurs as a result of
successful assembly of the pre-TCR
which of the following processes is most likely occurring in germinal center B cells?
switching from IgM to IgG
within light chain recombination process, what are the results of hairpin cleavage?
symmetrical opening leading to a blunt end; asymmetrical openings leading to 3' and 5' overhangs; asymmetrical opening leading to a 5' overhang; asymmetrical opening leading to a 3' overhang
licensing on an NK cell refers to
testing an NK cell to ensure that it will not target healthy host cells
Fc-receptor molecules tend to have short cytoplasmic tails. how does this influence signaling events within the Fc-receptor cell?
the Fc-receptor is dependent upon a coreceptor (ITAM or ITIM) that will trigger signaling events within the cell
the difference between NK cells and T lymphocytes is:
the amount of time it takes fo their level to increase in a patient with a viral infection; their receptors that bind to MHC I molecules
an example of ectopic lymphoid tissue would be follicles located in
the kidneys
if you suspect your patient may have lupus, what would you measure?
the level of anti-dsDNA IgG
the y-axis label of ELISA data is often "O.D.". what does this refer to?
the light emitted from the enzyme/substrate reaction
which of the following best describes the patient with non-functional AID?
the patient will only have IgM antibodies
what is the best definition of immunity?
the state of being resistant to reinfection with a pathogen
(Bates) the main difference between immunohistochemistry and ELISA is?
the type of sample used
the human MHC locus is one of the most polymorphic regions of the genome. what does this mean?
there are many different alleles of these genes
what happens to auto reactive cells that escape the thymus
they attack self-tissues; they can be rendered anergic; they negatively regulate other auto reactive cells; they require TCR ligation and costimulation to be activated
most people are exposed to DHA when
they eat fish
NK receptors are encoded in the germ line and are described by all of these except
they recognize likely pathogen
the results of a gel electrophoresis are shown in the picture. you must choose all correct statements regarding the gel to receive credit.
this gel electrophoresis was performed to complete an EMSA; sample 1 contains proteins attached to DNA
Fc
this region contains the constant of the heavy chain; this region determines the isotope of the antibody; if an opsonizing antibody to a virus, this region could bind to receptors on a phagocytic cells and then signal for the virus/antibody complex to be phagocytosed
naive CD4+ and CD8+ T cells leave the _____ and enter circulation.
thymus
which of the following is a potential cause of chronic inflammation?
tissue damage; intestinal commensal microbiota components; infectious agents; obesity
the role of cell mediated immunity is
to find and eliminate cells infected with intracellular pathogens
follicular helper T cells are a recent discovery in the helper T cell lineage. what is the primary role of Tfh cells?
to help B cell development in germinal centers
what is the function of a memory T cell?
to provide an almost immediate response upon subsequent exposure to a specific pathogen
two different B cells can have antibodies that have the same variable regions and different constant regions.
true
hypersensitivity reactions to cell surface antigens via IgG or IgM are classified as which type?
type II hypersensitivity
what types of cells are good targets for natural killer cells and why?
virally infected cells because they have low levels of class I MHC
put the following events in the correct order demonstrating the events that occur after a virus has entered the respiratory tract or digestive tract.
virus binds to TLRs on epithelial cells --> interferon alpha is secreted --> NK cells divide and differentiate --> NK cells induce apoptosis of infected cells
ELISA
y axis label- ng/ml performed in liquid sample uses antibodies to detect specific molecules
Immunohistochemistry (IHC)
y-axis label - % stained tissue performed on tissue biopsies uses antibodies to detect specific molecules