This type of elution is a method mainly used to release antibody molecules from the red cell membrane (when tests show the DAT is positive) for the purposes of identifying the antibody.
Investigation of HDN: an elution is done on the infant's red cells, and the resulting eluate is tested for the presence of the mother's IgG antibody which has crossed the placenta and sensitized fetal cells.
Investigation of IAHA (warm, cold, and drug-related types): an elution is done on the patient's red cells and the resulting eluate is tested for autoantibody specificity.
Investigation of hemolytic transfusion reactions: an elution is done on the patient's post-transfusion red cells, and the resulting eluate tested for antibody specificity. Note that in this case, even though the antibody elutes from the patient's red cells, it is not an autoantibody as it actually eluted from the donor's red cells now in the patient's circulation.
Separation of multiple antibodies to aid identification.
Confirmation of antibody specificity.
In cases of HDN, AIHA, and hemolytic transfusion reactions it is necessary to elute the antibody sensitizing the patient's red cells and to identify it by testing the eluate against a panel. There are numerous methods available for this type of elution, including Rubin's diethyl ether, Landsteiner heat at 56°C, chloroform, xylene, and acid elutions. These methods cause intact antibody to be released from the red cells either by disrupting the antigens, or by creating conditions that favour dissociation of antibody from antigen, although the exact mechanisms by which they elute antibody are not clear.
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| Elution (antibody identification) |
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