Antigen Antibody Interactions Flashcards

6449568658	the antigen antibody interaction is used to detect...	presence and/or concentration of a target antigen or antibody	0
6449571231	what are you actually measuring in an antigen-antibody interaction?	immune complex	1
6449574180	is the Ag-Ab interaction covalent?	no	2
6449580055	the precipitin reaction is based on the concept of complexing Ab-Ag forming...	immune complexes	3
6449582981	precipitation of Ag-Ab in precipitin reaction occurs due to...	insoluble lattice formation	4
6449588867	Lattice formation in precipitin reaction is optimal during the ___ zone when the concentration of antibody and antigen are such that one antigen bridges ___ Ab molecules	equivalence 2	5
6449591933	what happens in areas of Ab excess and Ag excess to the immune complexes?	they are small and soluble	6
6449598634	what are the rapid visible assays to see Ag-Ab interaction?	precipitation (soluble ag) agglutination (particulate Ag) activation of complement - lysis of RBC	7
6449601689	what are the longer, more sensitive assays to see Ag-Ab interaction?	labeled reactant instrumentation	8
6449631268	what does a direct assay measure?	antibody specific for target antigen;	9
6449638716	what is the detection antibody in direct assay?	primary antibody	10
6449637365	what does an indirect assay measure?	anti-Ig antibody that has bound to the target antibody-antigen complex;	11
6449641400	what is the detection antibody in indirect assay?	secondary antibody	12
6449643600	secondary antibody in indirect assay binds to _______ portion of target	Fc region	13
6449654170	what is the concept behind titer in the Ag-Ab interaction?	antibody serially diluted and equivalent amounts of Ag added to each tube; visualize different degrees of the immune complex	14
6449662981	when might you want to know Ab titers?	time course of infection - isotype and concentration absence of titer - no infection or immunodeficiences	15
6449669878	cross linking of Ab's is dependent on correct proportion of....	Ag-Ab	16
6449676172	what is direct agglutination?	particulate antigens - RBC, bacteria	17
6449677566	agglutination with RBC is called...	hemagglutination	18
6449681860	what is passive agglutination?	soluble antigen is firmly attached to a particle (latex bead)	19
6449688967	in passive agglutination, why must you firmly attach Ag to a particle before adding antibody?	because antibody would absorb all Ag and not attach to the particle - concept of agglutination inhibition	20
6449823601	due to principle of precipitin curve, particulate antigens will agglutinate during....	equivalence zone	21
6449826923	what is titer?	highest dilution at which cross linking of particulate antigen is seen	22
6449831831	what happens in the prozone?	too much Ab inhibits cross linking of particles	23
6449839114	ABO typing is a common application of what assay?	agglutination (specifically hemagglutination)	24
6449842315	ABO typing is due to _____ in our blood -	isohemagglutinins	25
6449847474	in blood banking, isohemagglutinins refers to ...	natural occurring antibodies to ABO blood types	26
6449854370	if you form agglutinate A, that means you have blood type...	B	27
6449860781	positive agglutination to a slide coated with antibody to organism or antibody to specific antigen would determine what about the patient?	infected	28
6449870220	does positive antibody response with agglutination mean you are infected right now?	no	29
6449881545	slide tests for agglutination show...	formation of large aggregates easily read on glass slide	30
6449885497	in agglutination in wells, what is a positive reaction? negative reaction?	positive reaction will be diffuse on bottom of the well negative reaction will be a button	31
6449893164	titer is the maximum dilution that gives visible..	agglutination	32
6449905217	hemagluttination inhibition assay is used to detect infection with...	influenza virus	33
6449908215	influenza virus has hemagglutinin protein on its surface that binds to sialic acid on ________	RBC	34
6449914104	if patient has not made influenza antibodies, what does the virus do to the RBCs?	agglutination occurs in the wells	35
6449919988	if you incubate patients' serum with the influenza virus, what happens if patient has made antibodies?	Abs will bind the virus and INHIBIT virus from binding RBCs and no agglutination occurs (red dot in wells)	36
6449928818	a positive or negative result of hemagglutination inhibition assay means you have antibody?	negative	37
6449938166	does agglutination always happen? why?	no because sometimes particulate antigens don't get close enough together to allow Ig molecule to bridge 2 particles	38
6449947460	Coombs test uses an ________ for the test	anti-immunoglobulin	39
6449951188	an anti-immunoglobulin is made in....	another species	40
6449952432	the anti immunoglobulin recognizes what portion of antibody	Fc	41
6449958284	coomb's test anti immunoglobulin recognizes antibody bound to an antigen via its ___ fragment	Fab	42
6449960910	what is direct coomb's test?	heterologous anti immunoglobulin is mixed with particles being tested for presence of antigen; looking for antibody bound to RBCs	43
6449965766	what is the antigen in direct coomb's test?	Ig	44
6449974066	what does indirect coomb's test detect?	detect presence of antigens (ab specific to particle) in the serum	45
6449992015	in the first step of indirect Coomb's test, you isolate patient's ___ and then add ___	serum target RBCs	46
6450031276	in the second step of indirect coomb's test, you add _____ which causes what if it is positive?	coombs reagent agglutination if positive	47
6450047620	Coombs test is especially important in testing for what disease?	hemolytic disease of the newborn	48
6450050219	describe the direct coombs test for hemolytic disease of the newborn (Rh- mother; Rh+ babby)?	take fetal RBC and determine if they agglutinate when adding coombs reagent; if they agglutinate, then fetal RBCs are coated with maternal anti-Rh antibody	49
6450063952	describe the indirect coombs test for hemolytic disease of the newborn (Rh- mother; Rh+ babby)?	take serum from mother and incubate with Rh+ RBC; add coombs reagent and if the test is positive there will be agglutination	50
6450074734	different between direct and indirect coombs test?	direct measures ab's already bound to particle indirect measures antibodies present in the serum	51
6450239368	in a precipitin reaction in solution, precipitation occurs when a divalent antibody molecules cross links ___ forming a ______	2 Ag molecules lattice	52
6450244053	when the lattice reaches a certain size, what happens to the precipitin reaction in solution?	loses its solubility and precipitates out of solution	53
6450249008	in a solid precipitin reaction, what happens?	soluble antigens and antibodies are added to wells in agar; they diffuse and while in equivalence zone there is precipitation that can be visualized	54
6450274594	explain the process of immunoblotting/western blotting	proteins are denatured, loaded into acrylamide gel plate and subjected to electrical current that causes proteins to migrate based on size; transfer proteins from gel onto a membrane, incubate membrane with antibodies to identify protein of interest	55
6450281447	migration of proteins in western blotting is relative to their...	weight	56
6450292548	____ infection is commonly diagnosed using Western blotting	HIV	57
6450328353	point of care systems use rapid diagnosis as their key where the principle of these tests is...	blotting	58
6450331849	how do these point of care systems work?	Ag or Ab is spotted on a strip; patient adds their fluid; kid fluids are added with detection; color change indicates positivity	59
6450334570	immunocap tests for...	hypersensitivity	60
6450338024	what is the immunocap test?	membrane spotted with various common allergens	61
6450339274	immunocap test tests for which specific antibody?	IgE	62
6450341363	streptatest tests for..	bacterial pharyngitis (strep throat)	63
6450344164	streptatest detects ____ antigens in throat swabs	group A Streptococcus	64
6450346258	in streptatest, the antibody to GAS is located where?	on the strip itself	65
6450367598	______ are assays based on the measurement of radioactivity associated with immune complexes	radioimmunoassays (RIAs)	66
6450370474	______ are those assays that are based on the measurement of an enzymatic reaction associated with immune complexes	ELISA	67
6450387996	how is a RIA done?	known amount of radiolabeled Ag mixed with limited antibody so that there will be unlabeled antigen which can be measured; separate bound and unbound and measure bound label	68
6450435504	what is competitive RIA?	determines an unknown concentration of antigen in serum	69
6450438333	how is competitive RIA done/what is measured?	known amount of labeled antigen is added and allowed to bind with antibody; unknown antigen is added and competes with labeled antigen. the unlabeled antigen will bind more readily and displaces labeled; measure ratio of the two	70
6450457938	what is the concept behind ELISA?	detect ag or ab based on ability of plastics to absorb monolayers of protein	71
6450467477	how is ELISA done?	coat wells with Ag, block unbound sites, add enzyme labeled Ab; Ab specific to the antigen binds the adsorbed antigen; add chromogenic substrate that reacts with enzyme labeled antibody and colormetric readout correlates with amount of antibody bound	72
6450482884	is ELISA quantitative?	yes - dilution for titer or inhibition assays (competitive ELISA)	73
6450484370	is ELISA qualitative?	yes	74
6450491619	how is sandwich ELISA done?	coat plate with Ag specific antibody, add specimin; second antibody specific to antigen of interest is added that will recognize bound antigen if present; anti immunoglobulin that is enzyme labeled is added that recognizes second antibody; substrate is added which the enzyme cleaves and results in color change	75
6450524533	immunofluorescence has a fluorescent group covalently linked to ____ portion of Ab	Fc	76
6450525863	immunofluorescence can be done in two ways	direct indirect	77
6450541599	_____ expressed on cells/microorganisms can be detected by labeled antibodies	epitopes	78
6450544229	immunohistochemistry is common for detection of specific antigens in ___ and detection of ____	tissues microorganisms	79
6450548042	IHC and IF used for identifying (3)	cell type organism protein expression	80
6450553393	flow cytometry uses immunofluorescence to determine....	immune cell types and to label and count number of cells	81
6450562758	what does a complement fixation assay determine?	patient has specific Ab or Ag	82
6450564805	what does a CH50 test?	tests functioning of patients classic complement pathway	83
6450570159	both complement activation assays need indicator cells which are..	sensitized sheep RBCs (SRBCs)	84
6450581732	in the first stage of complement fixation, you determine if the patient has an antibody to...	specific antigen	85
6450591328	stage 1 complement fixation: if patient has ab + ag binding, what happens?	immune complex formed and IC will fix complement if appropriate antibody isotype is there	86
6450598634	in complement fixation stage 2, you first have to determine if there were _____ formed in stage 1	complement activating immune complexes by amount present, if none present or less, then they were formed	87
6450604912	complement fixation stage 2: complement from stage 1 reaction is added to the ____	ab-SRBC complexes	88
6450610147	in complement fixation stage 2, amount of lysis or SRBC is directly or indirectly correlated with concentration of Ag-Ab complexes made in stage 1	indirectly	89
6450611900	if there is lysis of SRBC in complement fixation stage 2, did the patient have the antibody?	no	90
6450616755	in CH50 assay, the complement activity in plasma is measured by testing the ability of the patient's serum to lysis .....	antibody coated SRBC	91
6450619381	CH50 indicates if there is an absence or reduction of activity by any ______	complement component in the pathway	92
6450622350	when Ab coated RBC are incubated with normal plasma, the ___ pathway is activated which results in lysis of RBC	classical	93
6450626847	if a complement component is reduced, the CH50 levels will be greater less than or normal?	less than normal	94
6450630360	if a complement component is absent, the CH50 level will be...	zero	95
6450662004	______ ability of Ab to aggregate particulate antigens	agglutination	96
6450662011	______ ability of Ab to precipitate soluble antigens	immunodiffusion	97
6450665984	_______ ab are chemically modified to quantitate antigens	immunoassays	98
6450669075	____ ab's are labeled with fluorochromes and antigen positive cells can be visualized	immunofluorescence and FACs	99
6450675068	crucial steps for semi-quantification/quantification 1.) use of ___ 2.) use of _____ antibody or antigen 3.) at least on reagent must be in __ form 4.) must be able to separate ______	titers competitive pure bound from unbound	100