Blood Bank Ch 3: Blood Banking Reagents Overview and Applications

Which of the following is NOT an advantage of using a monoclonal antibody over a polyclonal antibody? - There are very few variations between lots. - There are no contaminating antibodies. - Direct agglutination is usually faster. - All variations of the antigen can be detected

All variations of the antigen can be detected

Reagent to identify the specificity of a red cell antibody

Panel cells

Following centrifugation of the gel card, red cells are evenly dispersed throughout one of the microtubes. This reaction could be graded as a:

2+

What temperature is used for incubation in the indirect antihuman globulin test? - 22° C - 37° C - 4° C - 56° C

37° C

In the solid-phase red cell adherence test, how does a negative test appear? - A button of cells on the bottom of the well - Adherence of cells along the sides and bottom of the wells - Hemolysis of red cells - A line of cells along the top of the well

A button of cells on the bottom of the well

Reagent used in the identification of ABO antibodies

A1 and B cells

Reagent used to determine the ABO antigenic composition of a patient's red cells

ABO antisera

Which of the following items provides evidence for reagent red cell deterioration? - Spontaneous agglutination - Significant hemolysis - Loss of agglutination strength over time - All of the above

All of the above

Which of the following statements is true regarding high-protein anti-D reagents? - They have been largely replaced with low-protein monoclonal reagents. - They contain approximately 20% bovine albumin. - They may increase the possibility of a false-positive reaction, requiring the use of a control. - All of the above are true.

All of the above are true

What specificities does polyspecific antihuman globulin contain? - Anti-IgG. - Anti-C3b and anti-C3d. - Anti-IgG and anti-C3d. - Anti-IgG and anti-IgM.

Anti-IgG and anti-C3d

Which of the following red cell antigens do proteolytic enzymes destroy? - Rh system antigens - Antigens Fya and Fyb in the Duffy system - Antigens in the Kidd system - Lewis system antigens

Antigens Fya and Fyb in the Duffy system

Select the test that uses IgG-sensitized red cells (check cells). - Antiglobulin test - D-antigen typing - Rh-antigen typing - B-antigen detection

Antiglobulin test

Antiglobulin test(s) that detects IgG or complement-coated red cells

Both the direct and indirect antiglobulin test

Antiglobulin test(s) that requires washing the cells several times before the addition of antihuman globulin reagent

Both the direct and indirect antiglobulin test

What is the purpose of adding antibody-sensitized red cells following the antiglobulin test?

Check that the wash procedure was sufficient to remove unbound antibodies

Antiglobulin test(s) that tests for certain clinical conditions such as hemolytic disease of the newborn and autoimmune hemolytic anemia

Direct antiglobulin test

antiglobulin test(s) in which incubation step is not necessary

Direct antiglobulin test

Select the method that uses a dextran-acrylamide matrix. - Solid-phase red cell adherence - Microplate - Gel technology - Tube techniques

Gel technology

What immunoglobulin class reacts best by antiglobulin testing?

IgG

Why is polyethylene glycol reagent added to the screen or panel?

Increase the avidity of IgG antibodies

Reagent derived from plants used to distinguish group A1 from group A2 red cells

Lectins

What reagent contains antibodies to multiple antigenic epitopes?

Polyclonal-based

Which red cells are used to screen for antibodies in donor samples? - Screening cells (two vials) - Pooled screening cells - Panel cells - Screening cells (three vials)

Pooled screening cells

Where are product limitations and technical considerations for each reagent located?

Product insert

Reagent to detect the presence of red cell antibodies

Screening cells

Why is incubation omitted in the direct antihuman globulin test?

The antigen-antibody complex has already formed in vivo

The antiglobulin test was performed using gel technology. A button of cells was observed at the bottom of the microtube following centrifugation. How do you interpret this result? - There is a problem with the card. - The result is a negative reaction. - The result is a strong positive reaction. - The test was not washed correctly.

The result is a negative reaction

Which of the following statements is true regarding IgG-sensitized red cells? - They must be used to confirm a negative antiglobulin tube test. - They must be used to confirm a positive antiglobulin test. - They must be used to confirm a direct antiglobulin test that was negative with anti-C3d. - They should be used only with the indirect antiglobulin test.

They must be used to confirm a negative antiglobulin tube test

How would you interpret the results if both the anti-D reagent and the Rh control were 2+ agglutination reactions?

Unable to determine without further testing

Rouleaux is a false-positive reaction that would not likely be observed during which of the following tests? - Immediate-spin antibody screen - Weak D test - Reverse typing in the ABO test - ABO forward typing

Weak D test

The gel technology method uses a concentration of red cells that is:

lower than tube techniques (gel method uses 0.8% suspension of red cells)

Reagent antibodies prepared from human sources are: - unsafe. - too low in potency to be effective. - polyclonal in specificity. - preferred because of their lower cost

polyclonal in specificity

Solid-phase red cell adherence used for antibody detection has an advantage over tube testing because:

the endpoint is more clearly defined

Monoclonal antibodies are prepared in:

vitro