Abstract | BACKGROUND: D- patients may receive Rh immunoglobulin (RhIg) before blood samples are taken for estimation of the volume of fetomaternal hemorrhage (FMH) by flow cytometry. Anti-D bound to the fetal D+ cells may then block the binding of conjugated D MoAb. This may reduce the fluorescence of the D+ cells, which would lead to ambiguity over setting the positions of the markers on histograms and may result in erroneous values of FMH. STUDY DESIGN AND METHODS: Labeling methods were compared by using FITC-BRAD 3 ( anti-D) and/or FITC- anti-IgG ( Fab fragment) with mixtures of D+ (R1r) and D- (rr) cells when the D+ cells had first been coated with various amounts (0 molecules/cell and 600-13,000 molecules/cell) of anti-D (RhIg). Variables examined were antibody concentrations, the order and times of incubation with the antibodies, and the effect of washing between the uptake of the antibodies used. RESULTS: In all cases, D+ cells were strongly labeled after incubation with 50 microL of FITC-BRAD-3 and then after washing with 50 microL of FITC-anti-human IgG, with both incubations being for 30 minutes at 37 degrees C. With this double-staining procedure, the fluorescence of D+ cells was found to be similar regardless of how much anti-D (RhIg) was previously bound and greater than that with FITC-BRAD-3 alone, giving an enhanced signal-to-noise ratio. CONCLUSION: As the testing laboratory may not know if the patient has received prophylactic RhIg, this labeling method would be suitable for all samples.
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Authors | B M Kumpel |
Journal | Transfusion
(Transfusion)
Vol. 41
Issue 8
Pg. 1059-63
(Aug 2001)
ISSN: 0041-1132 [Print] United States |
PMID | 11493739
(Publication Type: Comparative Study, Journal Article)
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Chemical References |
- Antibodies, Monoclonal
- Isoantibodies
- Rh-Hr Blood-Group System
- Rho(D) antigen
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Topics |
- Adult
- Antibodies, Monoclonal
- Erythrocytes
(immunology, metabolism)
- Female
- Fetal Blood
- Fetomaternal Transfusion
(blood, diagnosis, immunology)
- Flow Cytometry
(methods, standards)
- Humans
- Isoantibodies
(analysis, metabolism)
- Pregnancy
- Rh-Hr Blood-Group System
(immunology)
- Sensitivity and Specificity
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