Deck 3: Blood Bank Applications of Antigenantibody Reactions

Question 1

In transfusion medicine,the antihuman globulin (AHG)technique is used for numerous purposes including

A)Analyzing DNA
B)Detecting unexpected antibodies
C)Diagnosing the presence of human globulin
D)Inspecting microorganisms

Answer 1

Detecting unexpected antibodies

Question 2

All of the following can cause false results in both an indirect (IAT)or direct (DAT)antiglobulin test except

A)Contaminated saline
B)Inadequate incubation
C)Interruption in testing
D)Improper centrifugation

Answer 2

Inadequate incubation

Question 3

Which of the following would be a disadvantage to using a monoclonal reagent?

A)No contaminating antibodies
B)Small variation between batches
C)Specificity may be relative
D)Unlimited production

Answer 3

Specificity may be relative

Question 4

For tube testing,the most commonly used plasma-to-cell ratio is

A)One drop of plasma and one drop of 5% suspension of red blood cells
B)One drop of plasma and two drops 5% suspension of red blood cells
C)Two drops of plasma and one drop of 5% suspension of red blood cells
D)Two drops of plasma and two drops of 5% suspension of red blood cells

Question 5

Which of the following tests does not detect antibodies to red blood cell antigens?

A)Antibody screen
B)Antibody identification
C)Antigen typing
D)Crossmatch

Question 6

During the AHG phase of an antibody screen test,before adding AHG reagent to the test tubes,what should the red blood cells be washed with?

A)Distilled water
B)Iodine
C)Saline
D)Soap

Question 7

All of the following statements are true regarding the indirect antiglobulin test (IAT)except

A)Begins with a source of antigen and antibody being added to the test system
B)Consists of a two-step method
C)Has a first step where anti-IgG attaches to any IgG coating the red blood cells
D)Is a very versatile test within the blood bank laboratory

Question 8

Antihuman globulin (AHG)reagent must contain anti-_____ when used for antibody detection.

A)C3d
B)IgA
C)IgG
D)IgM

Question 9

Which of the following does not activate complement?

A)IgG1
B)IgG2
C)IgG3
D)IgG4

Question 10

Antibody screen tests must include an incubation step at what temperature,which is the optimal reaction temperature for IgG antibodies?

A)39.2° F (4° C)
B)71.6° F (22° C)
C)91.4° F (33° C)
D)98.6° F (37° C)

Question 11

The antihuman globulin technique is used to detect which isotype of antibody?

A)IgD
B)IgE
C)IgG
D)IgM

Question 12

The primary purpose of the immediate spin phase is to detect antibodies that react at room temperature,typically antibodies of the _____ class.

A)IgA
B)IgE
C)IgG
D)IgM

Question 13

_________ is typically added before the incubation phase of the antibody screen test.

A)AHG
B)DAT
C)IgG
D)PEG

Question 14

When the body first encounters a foreign antigen,a primary immune response is stimulated.One of the residual effects of the primary response is the retention of which memory cells?

A)B
B)D
C)X
D)Y

Question 15

When grading agglutination in a gel microtubule system,which grade is described as cells and agglutinates distributed through the column?

A)1+
B)2+
C)3+
D)4+

Question 16

The most common cause for the check cells not reacting is

A)Incorrect use of tubes
B)Improper washing
C)Malfunctioning equipment
D)Too much time in the centrifuge

Question 17

All of the following are characteristics of IgG except

A)Demonstrates agglutination in antiglobulin tests
B)Has a plasma half-life of about 23 days
C)Has a valence of 10
D)Is able to cross the placenta

Question 18

All of the following are true regarding the direct antiglobulin test (DAT)except

A)Detects sensitization in vivo of red blood cells with antibody or complement
B)Is performed in order to visualize antigen-antibody reactions that happened in the body,not the test tube
C)Is usually included in routine pretransfusion testing
D)Omits the incubation at 98.6° F (37° C)phase

Question 19

During the incubation phase of an antibody screen test,how long should the test tubes be incubated?

A)5-10 minutes
B)10-30 minutes
C)Depends on the temperature of incubation
D)Depends on the enhancement reagent added

Question 20

______ is the first immunoglobulin class produced in a primary immune response.

A)IgD
B)IgE
C)IgG
D)IgM