MLS 413 antibody identification and crossmatching
Questions With Complete Solutions
# of Donor Units to antigen type Correct Answers # of Antigen
Negative Donor Units Ordered for Crossmatch/Incidence of
Antigen Negative Donors in the Population
always round up
3 negative cell lines at AHG that are C(0) K(0) Correct Answers
Yes - Panel Cell Lines 3, 4, 6, 8, 9, & 10; Screen Cell Line II
A neg choices Correct Answers A neg
O neg
O neg
O neg
A pos choices Correct Answers A pos
A neg
O pos
O neg
AB neg choices Correct Answers AB neg
A neg*
B neg*
O neg*
AB pos choices Correct Answers AB pos
AB neg
A pos
A neg*
,Anti-C Correct Answers 3 positive cell lines at AHG that are
C(+) K(0)
YES - Panel Cell Lines 2 & TC, Screen Cell Line I
Panel Cell Lines 1 & 5 cannot be used as they are C(+) K(+)
Anti-K Correct Answers 3 positive lines that are C(0) K(+)
No - Panel Cell Lines 7, Screen Cell Line III
Panel Cell Lines 1 & 5 cannot be used as they are C(+) K(+)
Antibody ID: Tube Method Procedure
1-3 Correct Answers 1. Label 10-20 tubes respectively: "1",
"2", "3", etc. (correlating to the panel cell line, include patient
initials as well as tech initials) and one tube labelled "AC" (auto-
control)
2. Place 2 drops patient serum/plasma (Antibody) into each tube
3. Place 1 drop of Panel Cell 1, 2, 3, etc. (Antigen) into the
corresponding tube. Place 1 drop 3-5% patient RBCs into AC
tube
Immediate Spin (IS) Phase: Not required unless an ABO
discrepancy was detected → (spin/read/record)
Antibody ID: Tube Method Procedure
37°C Phase: "Sensitization" Phase
4-5 Correct Answers 4. Add two drops of Potentiator
(Enhancement Reagent) to each tube and place in a 37°C heat
block
, 5. Remove from heat block
-Depending on the potentiator used, tubes may or may not be
interpreted for agglutination following incubation
If positive in the IS or 37°C phase, you must continue testing
through the AHG phase to see if the reaction strength changes or
disappears
Antibody ID: Tube Method Procedure
AHG Phase: "Agglutination Detection" Phase Correct Answers
6. Wash all tubes three times (following a Cell Wash Procedure)
7. Add two drops of AHG to each tube (Purpose: AHG forms
visual agglutination: Ag/Ab complex on RBC + Anti-IgG)
8. Mix well and centrifuge
9. Gently re-suspend cells and observe for macroscopic
agglutination in the tube and grade positive reaction strengths
(Purpose: Differing reaction strengths could indicate the
presence of multiple antibodies or dosage)
-Depending on the potentiator used, if no macroscopic
agglutination is seen, further microscopic examination may be
required
10. To only the tubes which are negative after completion of the
AHG phase, add one drop of Coombs Control Cells (Check
Cells) (Purpose: Check to make sure AHG Reagent was not
neutralized)
Questions With Complete Solutions
# of Donor Units to antigen type Correct Answers # of Antigen
Negative Donor Units Ordered for Crossmatch/Incidence of
Antigen Negative Donors in the Population
always round up
3 negative cell lines at AHG that are C(0) K(0) Correct Answers
Yes - Panel Cell Lines 3, 4, 6, 8, 9, & 10; Screen Cell Line II
A neg choices Correct Answers A neg
O neg
O neg
O neg
A pos choices Correct Answers A pos
A neg
O pos
O neg
AB neg choices Correct Answers AB neg
A neg*
B neg*
O neg*
AB pos choices Correct Answers AB pos
AB neg
A pos
A neg*
,Anti-C Correct Answers 3 positive cell lines at AHG that are
C(+) K(0)
YES - Panel Cell Lines 2 & TC, Screen Cell Line I
Panel Cell Lines 1 & 5 cannot be used as they are C(+) K(+)
Anti-K Correct Answers 3 positive lines that are C(0) K(+)
No - Panel Cell Lines 7, Screen Cell Line III
Panel Cell Lines 1 & 5 cannot be used as they are C(+) K(+)
Antibody ID: Tube Method Procedure
1-3 Correct Answers 1. Label 10-20 tubes respectively: "1",
"2", "3", etc. (correlating to the panel cell line, include patient
initials as well as tech initials) and one tube labelled "AC" (auto-
control)
2. Place 2 drops patient serum/plasma (Antibody) into each tube
3. Place 1 drop of Panel Cell 1, 2, 3, etc. (Antigen) into the
corresponding tube. Place 1 drop 3-5% patient RBCs into AC
tube
Immediate Spin (IS) Phase: Not required unless an ABO
discrepancy was detected → (spin/read/record)
Antibody ID: Tube Method Procedure
37°C Phase: "Sensitization" Phase
4-5 Correct Answers 4. Add two drops of Potentiator
(Enhancement Reagent) to each tube and place in a 37°C heat
block
, 5. Remove from heat block
-Depending on the potentiator used, tubes may or may not be
interpreted for agglutination following incubation
If positive in the IS or 37°C phase, you must continue testing
through the AHG phase to see if the reaction strength changes or
disappears
Antibody ID: Tube Method Procedure
AHG Phase: "Agglutination Detection" Phase Correct Answers
6. Wash all tubes three times (following a Cell Wash Procedure)
7. Add two drops of AHG to each tube (Purpose: AHG forms
visual agglutination: Ag/Ab complex on RBC + Anti-IgG)
8. Mix well and centrifuge
9. Gently re-suspend cells and observe for macroscopic
agglutination in the tube and grade positive reaction strengths
(Purpose: Differing reaction strengths could indicate the
presence of multiple antibodies or dosage)
-Depending on the potentiator used, if no macroscopic
agglutination is seen, further microscopic examination may be
required
10. To only the tubes which are negative after completion of the
AHG phase, add one drop of Coombs Control Cells (Check
Cells) (Purpose: Check to make sure AHG Reagent was not
neutralized)
