Lecture 14 Applications of immune response Flashcards
seronegative
individual not exposed to antigen yet
has no specific antibodies to that pathogen
Seropositive
Individual has been exposed to antigen
has produced specific antibodes to pathogen
What is immunoassay
Any in vitro test that uses antibody-antigen interactions to detect an antigen in a sample
Antibody concentration is determined by ________
serial dilution
________ is reciprocal of last dilution that gives detectable antigen-antibody reaction
Titer (concentration_
________ antibodies bind to various epitopes on an antigen
Polyclonal antibodies
after animals are immunized, ________ cells response, produce a mix of antibodies
multiple B cells
More ________ antigens will yield more antibodies
complex
________ are obtained from animals immunized with IgG from human serum
anti human IgG
________ recognize a single epitope
Monoclonal antibodies
________ antibodies are produced only in the laboratory
Monoclonal antibodies
Mabs can be used in
immunoassays or in therapy
Obiltoxaximab was produced by ________
Monoclonal antibodies
What is rhuMab
Recombinant humanized monoclonal antibody
What are differences of RbuMab over Mab
Longer half-life
immune system less likely to destroy antibodies
medications end in -zumab
used to treat cancers
Direct immunoassay
identify unknown antigen
in direct immunoassay, antigen is attached to
solid surface
indirect immunoassay
detect specific antibodies
in indirect immunoassay, known antigen is attached to surface, ________ is added
serum
In indirect immunoassay, ________ antibodies are added
secondary antibodies
What are the names of the secondary antibodies added in indirect immunoassay
anti-human IgG
Fluorescent antibody test uses fluorescence microscope to
locate labeled antibodies that are bound to antigens on a microscope slide
In fluorescent antibody test, what characteristic of the antigen is seen?
sizem shape
What is ELISA stand for
Enzyme linked immunosorbent assay
Direct ELISA is when antigen is ________ by antibodies attached to surface
________ antibody added to detect antigens
captured
enzyme-labeled
Indirect ELISA detects antibodies in ________
human blood and serum
What is indirect ELISA most commonly used for
Blood is screened for antibodies to HIV
How ELISA works
enzyme converts ________ to ________, detected using colorimetric assay
colorless substrate to colored product
A pregnancy test tests for the presence of ________ in urine
hCG
In a pregnancy test, if hCG is detected, it turns what color?
yellow
If hCG is present in urine, it binds to ________ and turns the first stripe yellow
surface bound antibodies
If hCG is present in urine, the second strip contains antibodies to the ________ which turns it yellow
Fab region of tagged antibody
The second strip on a pregnancy test is a ________
control
COVID antigen test tests for presence of ________
SARS-CoV2 spike antigen
in COVID test, ________ solution flows to detection strip containing surface bound antibodies
buffer
western blotting detects presence of specific protein in ________ mixture like cell lysate
Complex
in western blotting, proteins are separated by size using ________
SDS-PAGE
Type of gel electrophoresis
western blotting
proteins are transferred to ________ (blotted)
serum added, unbound antibodies are ________
________ is added
label is detected
nylon membrane
washed off
enzyme
What does the label on western blotting indicate
Which proteins on the blot were recognized by the antibodies in the serum
What does fluorescence activated cell sorter (FACS) do?
counts, sorts cells labeled with fluorescent antibodies
immunoassay may involve visible ________
antigen-antibody aggregates
Antibodes that cross-link antigens create larger ________ of ________ cells
mouthfuls of phagocytic cells
Clumped antigen-antibody complexes form the basis of
Agglutination, precipitation reactions
agglutination cross-links ________ particles
Large particles like cells
What is the direct agglutination test
Antibody mixes with antigen and binding causes clumping
________ is used for blood typing
Hemagglutination
________ agglutination used with antigens are small
Passive
in passive agglutination, antibodies are attached to ________ to form larger aggregates
Latex beads
in precipitation reactions, antibodies are bound to ________ antigens
soluble
in precipitation reactions, separate suspensions are placed near each other and allowed to ________
Diffuse, immunodiffusion
precipitate forms in zone of ________
optimal proportions
