Lecture #9: Antiglobulin Test Flashcards
it is obtained from immunized nonhuman species bind to human globulins such as IgG and complements
Antihuman globulins
one of the major type of blood group antibodies that directly agglutinate RBCs
IgM
IgM react best at what temperature?
due to its reaction on that specific temperature, it is also called as?
room temperature
cold-reacting antibody
why does it called nonagglutinating or incomplete antibodes?
this antibodies react best at wht temperature?
due to too small to directly agglutinate sensitized RBC
37 degree celcius
IgG antibodies are also called as … due to its characteristic in reacting specific temperture
warm-reacting antibodies
Adding AHG that contains IgG result
Hemagglutination
T/F. AHG can also be used to detect RBC sensitized with IgG alloantibodies, IgG antibodies, and complement components
True
senzitization can occur either _____ or _____
in vivo or in vitro
he used rabbit antigoat serum to agglutinate rabbit rbcs that were sensitized with low nonagglutinating doses of goat anti-rabbit RBC antgen
Moreschi
first application of the AHG test
Weak D Testing
who presented the first indication that there might be another antibody activity present tht influenced the final reaction
Dacie
T/F. it was Coombs and mourant demosntraed that the antibody activity that detected Rh antibodies was associated with the anti-gammaglobulin fraction in the reagent
True
what antibodies resulted from anti-gamma globulin activity
Warm antibodies
what antibodies resulted from anti-nongamma globulin activity
Cold antibodies
Which of the following are true in Nongamma globulin component
A. shown to be beta globulin
b. shown to be alpha globulin
c.had specificty for complement
d.doesnt have specificty for complement
e.complment activity was a result of c3 and c4
A, C, E
it contains antibody to human IgG and to the c3d component of human complement
Polyspecific AHG
contains only one antibody specificity, either anti-IgG or antibody to specific complement
monospecific AHG
T/F. If Anti-IgG reagent is not labeled as gamma heavy chain-specific, it may contain anti-light chain specificty, specifically anti-kappa and anti-lambda or it may not react with cells sensitized with IgM, IgA and IgG
False.
why? onsa naka false abir?
it is a mixture of antibodies from different plasma cell clones
polyspecific antibodies
this antibodies result in recognizing differet antigenic determinants, or the same portion of the antigen but with different affinities
polyspecific antibodies
what technology where monoclonal antibodies produced
hybridoma technology
what ahg production where rabbits is usually used and sheep or goats can also be used
polyspecific
what animal is usually used in monospecific
mouse
t/f.sheep or goats are used for smaller volumes
false
what is the reason why ant-IgG pool and anti-complement pool is absorbed with A1, B, and O cells
to remove heterospecific antibodies
what cells are fused with antibody-secreting lymphocyte in the spleen cells of mouse
myeloma cells
what contains the mouse spleen cells
antibody-secreting lymphocyte
what is the used of dyed green in the reagent of monoclonal specific
identification
T/F. All antibody molecules produced by a clone of hybridoma cells are identical in terms of antibody structure and antigen specificity
true
considered as one of the advantage o hybridoma technology in AHG production
available indefinitely
it is a one stage technique used to detect in vivo sensitization
direct antiglobulin test
what is the aim of DAT
to detect antibodies bound to rbc surface
how many IgG molecules per rbc does the DAT can detect?
how many c3d molecules per rbc does the DAT can detect?
100-500 IgG molecules
400-1,100 c3d molecules
which of the following are not included in clinical application for DAT
a. HDN
b. HTR
c. Rbc phenotyping
d. antibody screening and Identification
e. Autoimmune and drug-induced hemolytic anemia
c and d
it is a two stage technque used to determine in vitro sensitization of rbcs
indirect antiglobulin test
what reaction is obtained when there is 100-200 IgG or c3d molecules
positive
Identify what stage in IDAT in additional of coombs reagent to the test
2nd stage
what are the clinical applications for IDAT?
compatibility testing or crossmatching
antibody screening and Identification
rbc phenotyping
titration of incomplete antibodies
what is the purpose of incubating rbc with antisera
a. removes free globulin molecules
b. accelerates agglutinaton
c. allows time for antibody moleule attachment to rbc antigen
c
what is the purpose of centrifuge
a. accelerates agglutination by bringing the cells together
b. removes free globulin molecules
c. allows time for antibody molecule attachment to rbc antigen
d. forms rbc agglutinates
a
what is the purpose in prforming a minimum of three saline washes
a. accelerates agglutination by bringing the cells together
b. removes free globulin molecules
c. allows time for antibody molecule attachment to rbc antigen
d. forms rbc agglutinates
b
what is the purpose in adding antiglobulin reagent
a. accelerates agglutination by bringing the cells together
b. removes free globulin molecules
c. allows time for antibody molecule attachment to rbc antigen
d. forms rbc agglutinates
d
what should you do when you obtain a negative reaction in chu chu test
add check cells
wat task determines the strength of reaction
grade agglutination reactions
what confirms the presence of active AHG reagent in the test mixture
agglutination of check cells
are IgG-sensitized red cells, that if theres no agglutination, it will invaldates the tets
check cells
what is the ratio of serum to cells
40:1
what happens when there is increasing ratio of serum
increases the sensitivty of the test system
what reaction medium that its macromolecules allow antibody-coated cells to ocme into closer contact with each other, hence aggregation
albumin
Addition of albumin, _____ the incubation time
decreases
what reaction medium that reduces the zeta potential surrounding the rbc
low ionic strength solution
LISS medium may be achieved by either:
suspending rbc in liss or
using liss additive regent
what reaction medium that removes water molecules surrounding the rbc
polyethylene glycol
the following are characteristic of this reaction medium except:
a. water-soluble linear polymer
b. effectively concentrates antibody
c. water-insoluble
d. removes water molecules in the plasma or serum
e. used as an additive to increase antibody uptake
c and d
what is the incubation time for saline
30-120 mins
what is the incubation time for LISS or PEG
10-15 minutes
inadequate washing of rbc may result to
false negative
what is he pH of saline for washing
7.2-7.4
it is a CBER recommended for centrifugation for reading
1000 RCF for 20s
a potent rouleaux-forming reagent
polybrene
it is added to reverse rouleaux
high ionic strength solution
what technique is used that relies on low ionic condition to rapidly sensitize cells with antibody
low ionic polybrene technique
test that detecs rbc antigen-antibody reaction by means of using chamber
gel test
what gel filled in the chamber during gel test
polyacrylamide gel
T/F. washing is omitted in gel test
true
type of gel test that does not contain any specific reagent and acts only by its property of trapping agglutinates
neutral gel
what type of gel that a specific reagent is incorporated into the gel
specific gel
type of gel where ahg reagent incorporated into the gel
Gel LOw IOnic ANtiGLOBULIN tEST
centrifugation for GLIAT
910 rpm for 10 minutes
