Question 1

Why was anticomplement introduced into AHG sera?

Accepted Answer

A)  Certain clinically significant antibodies demonstrate complement activity. 
B)  Complement components enhance Kell antibodies. 
C)  It provides additional information for transfusion reaction workups. 
D)  All of the above 
A)  Certain clinically significant antibodies demonstrate complement activity. 
B)  Complement components enhance Kell antibodies. 
C)  It provides additional information for transfusion reaction workups. 
D)  All of the above D

Question 2

What class of antibody can be present in AHG?

Accepted Answer

A)  IgG 
B)  IgM 
C)  IgA 
D)  All of the above 
A)  IgG 
B)  IgM 
C)  IgA 
D)  All of the above D

Question 3

A patient came in for a routine type and screen prior to surgery. The antibody screen was negative at 37°C and at the AHG phase. Check cells did not produce agglutination often. What is a possible explanation for this result?

Accepted Answer

A)  Dirty glassware 
B)  Use of positive DAT cells 
C)  Inadequate washing 
D)  Overcentrifugation 
A)  Dirty glassware 
B)  Use of positive DAT cells 
C)  Inadequate washing 
D)  Overcentrifugation C

Question 4

All of the following statements regarding the AHG test are true except:

Accepted Answer

A)  when washing cells, all saline should be removed completely. 
B)  centrifugation should provide a firm pellet. 
C)  incubation time with LISS should be a minimum of 30 minutes. 
D)  Coombs' control cells should be added to all negative tubes. 
A)  when washing cells, all saline should be removed completely. 
B)  centrifugation should provide a firm pellet. 
C)  incubation time with LISS should be a minimum of 30 minutes. 
D)  Coombs' control cells should be added to all negative tubes.

Question 5

Why is the 37°C reading omitted when using PEG additive?

Accepted Answer

A)  PEG may cause aggregation of RBCs at 37°C. 
B)  Antibodies detected by PEG do not react at 37°C. 
C)  Warm-reacting antibodies are not clinically significant. 
D)  Unwanted reactions due to C3b will be detected at 37°C. 
A)  PEG may cause aggregation of RBCs at 37°C. 
B)  Antibodies detected by PEG do not react at 37°C. 
C)  Warm-reacting antibodies are not clinically significant. 
D)  Unwanted reactions due to C3b will be detected at 37°C.

Question 6

Most clinically significant blood group antibodies are of which IgG subclasses?

Accepted Answer

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

Question 7

What is a possible consequence of incubating tubes too long with LISS when performing the IAT?

Accepted Answer

A)  Increased sensitivity 
B)  Hemolysis 
C)  Elution of antibody from red blood cells 
D)  All of the above 
A)  Increased sensitivity 
B)  Hemolysis 
C)  Elution of antibody from red blood cells 
D)  All of the above

Question 8

The inability to determine the of anti-C3b and anti-C3d individually is one of the difficulties with polyclonal reagents.

Accepted Answer

A)  potency 
B)  titer 
C)  presence 
D)  volume 
A)  potency 
B)  titer 
C)  presence 
D)  volume

Question 9

What is the purpose of washing cells in the AHG test?

Accepted Answer

A)  To dilute serum 
B)  To remove all unbound protein 
C)  To remove all bound protein 
D)  To exclude a low-affinity antibody 
A)  To dilute serum 
B)  To remove all unbound protein 
C)  To remove all bound protein 
D)  To exclude a low-affinity antibody

Question 10

Saline used for blood banking tests should have a pH of .

Accepted Answer

A)  5.0 to 5.5 
B)  6.8 to 7.2 
C)  7.2 to 7.4 
D)  7.5 to 8.0 
A)  5.0 to 5.5 
B)  6.8 to 7.2 
C)  7.2 to 7.4 
D)  7.5 to 8.0

Question 11

False-negative results in antihuman globulin testing can be caused by:

Accepted Answer

A)  overcentrifugation. 
B)  undercentrifugation. 
C)  cell suspensions that are too weak or too heavy. 
D)  all of the above. 
A)  overcentrifugation. 
B)  undercentrifugation. 
C)  cell suspensions that are too weak or too heavy. 
D)  all of the above.

Question 12

A patient is discovered to have anti-Fya in their serum. The medical technologist needs to phenotype the patient's cells for the corresponding antigen. What test is appropriate for phenotyping?

Accepted Answer

A)  Absorption 
B)  Elution 
C)  DAT 
D)  IAT 
A)  Absorption 
B)  Elution 
C)  DAT 
D)  IAT

Question 13

What do "check cells" contain?

Accepted Answer

A)  A+ red blood cell coated with anti-D 
B)  Rh(
D) + red blood cells coated with anti-D 
C)  Rh(
D) - red blood cells coated with anti-D 
D)  B+ red blood cells coated with anti-D 
A)  A+ red blood cell coated with anti-D 
B)  Rh(
D) + red blood cells coated with anti-D 
C)  Rh(
D) - red blood cells coated with anti-D 
D)  B+ red blood cells coated with anti-D

Question 14

Why are check cells added to all negative reactions in the AHG test?

Accepted Answer

A)  To ensure AHG was not neutralized by free globulin molecules 
B)  To wash away any unbound antibody 
C)  To increase the cell-to-serum ratio 
D)  To bring the antibody closer to the antigen in the test system 
A)  To ensure AHG was not neutralized by free globulin molecules 
B)  To wash away any unbound antibody 
C)  To increase the cell-to-serum ratio 
D)  To bring the antibody closer to the antigen in the test system

Question 15

You are performing an IAT, and you are suspicious of the results. It appears there may be a weak alloantibody present. You decide to repeat the test, and at the LISS stage you decide to add an extra two drops of serum to each tube being tested. What can you expect to happen?

Accepted Answer

A)  There would be no effect. 
B)  The additional serum increases reaction strengths, because more possible antibody is added to the reaction. 
C)  Sensitivity of the test decreases, because you increased the ionic strength of the mixture. 
D)  You lowered the zeta potential, thus enhancing your results. 
A)  There would be no effect. 
B)  The additional serum increases reaction strengths, because more possible antibody is added to the reaction. 
C)  Sensitivity of the test decreases, because you increased the ionic strength of the mixture. 
D)  You lowered the zeta potential, thus enhancing your results.

Question 16

How would a negative IAT be demonstrated in solid phase methodology?

Accepted Answer

A)  The cells form a monolayer. 
B)  There is a pellet at the bottom of the well. 
C)  The well turns orange. 
D)  Small agglutinins appear at the bottom of the well. 
A)  The cells form a monolayer. 
B)  There is a pellet at the bottom of the well. 
C)  The well turns orange. 
D)  Small agglutinins appear at the bottom of the well.

Question 17

How is a 40:1 ratio of serum to cells prepared for the AHG test?

Accepted Answer

A)  5 drops of serum + 1 drop of a 5% v/v RBC suspension 
B)  1 drop of serum + 1 drop of a 5% v/v RBC suspension 
C)  2 drops of serum + 1 drop of a 5% v/v RBC suspension 
D)  1 drop of serum + 5 drops of a 5% v/v RBC suspension 
A)  5 drops of serum + 1 drop of a 5% v/v RBC suspension 
B)  1 drop of serum + 1 drop of a 5% v/v RBC suspension 
C)  2 drops of serum + 1 drop of a 5% v/v RBC suspension 
D)  1 drop of serum + 5 drops of a 5% v/v RBC suspension

Question 18

If not labeled "gamma heavy chain-specific," monospecific anti-IgG may contain antibodies to:

Accepted Answer

A)  immunoglobulin light chains. 
B)  alpha heavy chains. 
C)  mu heavy chains. 
D)  C3d. 
A)  immunoglobulin light chains. 
B)  alpha heavy chains. 
C)  mu heavy chains. 
D)  C3d.

Question 19

How is polyclonal antiglobulin serum made?

Accepted Answer

A)  Serum from one human is injected into another human, and an antibody is produced. 
B)  Human serum is injected into rabbits, and an immune response triggers the production of an antibody. 
C)  Murine serum is injected into rabbits, and an immune response triggers the production of an antibody. 
D)  Murine serum is injected into mice, and an immune response triggers the production of an antibody. 
A)  Serum from one human is injected into another human, and an antibody is produced. 
B)  Human serum is injected into rabbits, and an immune response triggers the production of an antibody. 
C)  Murine serum is injected into rabbits, and an immune response triggers the production of an antibody. 
D)  Murine serum is injected into mice, and an immune response triggers the production of an antibody.

Question 20

All of the following complement proteins can be found on the red blood cell membrane except:

Accepted Answer

A)  C3d 
B)  C4b 
C)  C4a 
D)  C4d 
A)  C3d 
B)  C4b 
C)  C4a 
D)  C4d

Exam 5: The Antiglobulin Test

Why was anticomplement introduced into AHG sera?

What class of antibody can be present in AHG?

A patient came in for a routine type and screen prior to surgery. The antibody screen was negative at 37°C and at the AHG phase. Check cells did not produce agglutination often. What is a possible explanation for this result?

All of the following statements regarding the AHG test are true except:

Why is the 37°C reading omitted when using PEG additive?

Most clinically significant blood group antibodies are of which IgG subclasses?

What is a possible consequence of incubating tubes too long with LISS when performing the IAT?

The inability to determine the of anti-C3b and anti-C3d individually is one of the difficulties with polyclonal reagents.

What is the purpose of washing cells in the AHG test?

Saline used for blood banking tests should have a pH of .

False-negative results in antihuman globulin testing can be caused by:

A patient is discovered to have anti-Fya in their serum. The medical technologist needs to phenotype the patient's cells for the corresponding antigen. What test is appropriate for phenotyping?

What do "check cells" contain?

Why are check cells added to all negative reactions in the AHG test?

You are performing an IAT, and you are suspicious of the results. It appears there may be a weak alloantibody present. You decide to repeat the test, and at the LISS stage you decide to add an extra two drops of serum to each tube being tested. What can you expect to happen?

How would a negative IAT be demonstrated in solid phase methodology?

How is a 40:1 ratio of serum to cells prepared for the AHG test?

If not labeled "gamma heavy chain-specific," monospecific anti-IgG may contain antibodies to:

How is polyclonal antiglobulin serum made?

All of the following complement proteins can be found on the red blood cell membrane except:

Red Blood Cells and Platelet Preservation: Historical Perspectives and Current Trends

Basic Genetics

Fundamentals of Immunology

Concepts in Molecular Biology

The Abo Blood Group System

The Rh Blood Group System

Blood Group Terminology and Common Blood Groups

Uncommon Blood Groups

Detection and Identification of Antibodies

Pre-Transfusion Testing

Blood Bank Technologies and Automation

Donor Selection

Transfusion-Transmitted Diseases

Component Preparation

Transfusion Therapy

Adverse Effects of Blood Transfusion

Apheresis

Cellular Therapy in the Transplant Setting

Hemolytic Disease of the Fetus and Newborn

Autoimmune Hemolytic Anemias

Tissue Banking As Part of the Transfusion Service

The Hla System

Relationship Testing

Quality Management

Patient Blood Management

Transfusion Safety and Federal Regulatory Requirements

Laboratory Information Systems in the Blood Bank

Medicolegal and Ethical Aspects of Providing Blood Collection and Transfusion Services

Filters

A patient is discovered to have anti-Fy^a in their serum. The medical technologist needs to phenotype the patient's cells for the corresponding antigen. What test is appropriate for phenotyping?