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Blood Banking - Antibody detection and identification handout 2009
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Antibody Detection dand
IdentificationIdentification
Michelle BrownMichelle Brown
f dFrequency of unexpected antibodies in antibodies in hospitalized ppatients…2%
Purpose of Antibody Detection and IdentificationIdentification…
To detect and identify antibodies that are clinically significantclinically significant
What is a Clinically Significant y gAntibody?
An antibody that reacts at 37°C which can cause in vivo red cell which can cause in vivo red cell
destruction
What if you Have a Clinically S f b d ?Significant Antibody?
1 Identify the antibody1. Identify the antibody2. Find antigen negative blood3. Crossmatch compatible
What’s Clinically Significant?
Always Significant Sometimes SignificantAlways SignificantABORh
Sometimes SignificantLea
MN RhKellDuffy
MN P1
LutheranDuffyKiddSs
Lutheran
Rarely SignificantLeb
Xga
How do we Know if the Patient h b d ?has an Antibody?
They have a positive antibody screenscreen.
ABO Discrepancy – AB with anti-MAA B A1 B cell
M + M -
How do we know the Patient has an Antibody?
I tibl t hIncompatible crossmatchTransfusion reactionHDNPositive DATPositive auto control
What do we need for Antibody Identification?
ABO d RhABO and RhAntibody screenResults of previous testingHistory of transfusion or pregnancyDiagnosisMedicationsMedications
Reagent Red Cells - ABSCReagent Red Cells ABSC
G OGroup O
2-cell or 3-cell screens2 cell or 3 cell screens
Typed for all common antigens in j bl d tmajor blood group systems
Match lot # with antigen profile sheet Match lot # with antigen profile sheet (antigram)
Required Testing ParametersRequired Testing Parameters
M lMay use serum or plasmaMethods that will demonstrate li i ll i ifi t tib diclinically significant antibodies
Must include 37°C incubation and AHGAHGPolyspecific or anti-IgGIgG presensitized cells (check cells)
Antibody Panels
10 20 O t d ll10-20 group O reagent red cellsAntigram – indicates the phenotypes f th t d llof the reagent red cells
Pattern of reaction of patient serum i h ll i h d h f with cells is matched to the pattern of
antigen typing to determine the antibody specificityantibody specificity
D C E c e M N S s K k Fya
Fyb
Jka
Jkb
IS 37 AGT
1 0 + 0 + + + 0 + + 0 + + 0 + 0 0 0 0
2 + + 0 0 + + + + 0 0 + + + + 0 0 0 0
3 + + + 0 + 0 + 0 + 0 + + + 0 + 0 0 +3 0 0 0 0 0 0 0 +
4 + 0 + + 0 0 + + 0 + 0 0 + + + 0 0 +
5 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 05 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 0
6 0 0 + + + + + + + 0 + 0 + 0 + 0 0 +
7 + 0 0 + + 0 + 0 0 + + 0 0 + 0 0 0 0
8 0 0 0 + + + 0 0 + 0 + + + 0 + 0 0 0Pt 0 0 0
D C E c e M N S s K k Fya
Fyb
Jka
Jkb
IS 37 AGT
1 0 + 0 + + + 0 + + 0 + + 0 + 0 0 0 0
/ / / / / / / / // / / / /
2 + + 0 0 + + + + 0 0 + + + + 0 0 0 0
3 + + + 0 + 0 + 0 + 0 + + + 0 + 0 0 +3 0 0 0 0 0 0 0 +
4 + 0 + + 0 0 + + 0 + 0 0 + + + 0 0 +
5 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 05 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 0
6 0 0 + + + + + + + 0 + 0 + 0 + 0 0 +
7 + 0 0 + + 0 + 0 0 + + 0 0 + 0 0 0 0
8 0 0 0 + + + 0 0 + 0 + + + 0 + 0 0 0Pt 0 0 0
D C E c e M N S s K k Fya
Fyb
Jka
Jkb
IS 37 AGT
1 0 + 0 + + + 0 + + 0 + + 0 + 0 0 0 0
/ / / / / / / / /
2 + + 0 0 + + + + 0 0 + + + + 0 0 0 0
3 + + + 0 + 0 + 0 + 0 + + + 0 + 0 0 +3 0 0 0 0 0 0 0 +
4 + 0 + + 0 0 + + 0 + 0 0 + + + 0 0 +
5 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 05 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 0
6 0 0 + + + + + + + 0 + 0 + 0 + 0 0 +
7 + 0 0 + + 0 + 0 0 + + 0 0 + 0 0 0 0
8 0 0 0 + + + 0 0 + 0 + + + 0 + 0 0 0Pt 0 0 0
Evaluating Antibody Specificity
V i t th f ti itVarying strength of reactivityDosageM lti l tib diMultiple antibodiesVarying strength of antigen on red cells (P Le I Fy Jk D)(P, Le, I, Fy, Jk, D)
If difficult pattern, may phenotype the patients cells to see which the patients cells to see which antibodies they could make
Panel Interpretation
Some cells pos, some neg, auto neg
D C E c e M N S s K k Fya
Fyb
Jka
Jkb
IS 37 AGT
1 0 + 0 + + + 0 + + 0 + + 0 + 0 0 0 0
2 + + 0 0 + + + + 0 0 + + + + 0 0 0 0
3 + + + 0 + 0 + 0 + 0 + + + 0 + 0 0 +3 0 0 0 0 0 0 0 +
4 + 0 + + 0 0 + + 0 + 0 0 + + + 0 0 +
5 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 05 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 0
6 0 0 + + + + + + + 0 + 0 + 0 + 0 0 +
7 + 0 0 + + 0 + 0 0 + + 0 0 + 0 0 0 0
8 0 0 0 + + + 0 0 + 0 + + + 0 + 0 0 0Pt 0 0 0
Interpretation of Typical Panel Results
Some cells pos some neg auto negSome cells pos, some neg, auto negSingle alloantibody
Many or all cells pos, auto neg
D C E c e M N S s K k Fya
Fyb
Jka
Jkb
IS 37 AGT
1 0 + 0 + + + 0 + + 0 + + 0 + 0 0 0 +
2 + + 0 0 + + + + 0 0 + + + + 0 0 0 +
3 + + + 0 + 0 + 0 + 0 + + + 0 + 0 0 +3 0 0 0 0 0 0 0 +
4 + 0 + + 0 0 + + 0 + 0 0 + + + 0 0 +
5 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 +5 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 +
6 0 0 + + + + + + + 0 + 0 + 0 + 0 0 +
7 + 0 0 + + 0 + 0 0 + + 0 0 + 0 0 0 +
8 0 0 0 + + + 0 0 + 0 + + + 0 + 0 0 +Pt 0 0 0
Interpretation of Typical Panel Results
Some cells pos some neg auto negSome cells pos, some neg, auto negSingle alloantibody
Many or all cells pos, auto negy p , gMultiple antibodiesAntibody to high incidence antigen
Few cells pos, no evident patternD C E c e M N S s K k Fy
aFyb
Jka
Jkb
IS 37 AGT
1 0 + 0 + + + 0 + + 0 + + 0 + 0 + 0 0
2 + + 0 0 + + + + 0 0 + + + + 0 0 0 0
3 + + + 0 + 0 + 0 + 0 + + + 0 + 0 0 03 0 0 0 0 0 0 0 0
4 + 0 + + 0 0 + + 0 + 0 0 + + + 0 0 0
5 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 05 0 0 0 + + + + 0 + 0 + + 0 + + 0 0 0
6 0 0 + + + + + + + 0 + 0 + 0 + 0 0 0
7 + 0 0 + + 0 + 0 0 + + 0 0 + 0 0 0 0
8 0 0 0 + + + 0 0 + 0 + + + 0 + + 0 0Pt 0 0 0
Interpretation of Typical Panel Results
Some cells pos some neg auto negSome cells pos, some neg, auto negSingle alloantibody
Many or all cells pos, auto negy p , gMultiple antibodiesAntibody to high incidence antigen
Few cells pos no evident patternFew cells pos, no evident patternWeak antibodyAntibody showing dosageTechniques to enhance reactions?
All cells pos, including auto controlD C E c e M N S s K k Fy
aFyb
Jka
Jkb
1 0 + 0 + + + 0 + + 0 + + 0 + 0 +
2 + + 0 0 + + + + 0 0 + + + + 0 +
3 + + + 0 + 0 + 0 + 0 + + + 0 + +3 0 0 0 0 0 +
4 + 0 + + 0 0 + + 0 + 0 0 + + + +
5 0 0 0 + + + + 0 + 0 + + 0 + + +5 0 0 0 + + + + 0 + 0 + + 0 + + +
6 0 0 + + + + + + + 0 + 0 + 0 + +
7 + 0 0 + + 0 + 0 0 + + 0 0 + 0 +
8 0 0 0 + + + 0 0 + 0 + + + 0 + +Pt +
Interpretation of Typical Panel Results
Some cells pos some neg auto negSome cells pos, some neg, auto negSingle alloantibody
Many or all cells pos, auto negy p , gMultiple antibodiesAntibody to high incidence antigen
Few cells pos no evident patternFew cells pos, no evident patternWeak antibodyAntibody showing dosage
All cells pos, auto posCold autoantibodyWarm autoantibodyWarm autoantibodyRouleaux
Selected Cells
If d t h th ll If you don not have the cells on your panel to rule out an antibody, you need to run additional cellsneed to run additional cells
If d h h ll If you do not have the cells on your panel to prove an antibody, you need to run additional cellsto run additional cells
Methods of Testing for Antibody
Low Ionic Strength Solution (LISS)
+ ++
++
+
LISS
I iti itIncreases sensitivity
Don’t increase serum:cell ratio
Less sensitive method for detection of Kell antibodies
PEG
P l th l l lPolyethylene glycolRemoves water, concentrates the
tib d t tib d t k antibody, promotes antibody uptake, and enhances strength of reactionD ’ ifDon’t centrifugeUse anti-IgG for AGT
T t T bTest TubeGelSolid Phase Red Cell Adherence
Gel Test: Pos test Neg testPos test Neg test
Gel Test: Antibody Screeny
Gel Test: ABO Typing
Solid Phase Red Cell Adherence
Solid Phase Red Cell Adherence