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PubMed · 7587746

HLA-B27 screening by flow cytometry.

B Lingenfelter·T C Fuller·L Hartung·J Hunter·C Wittwer
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Abstract

A flow cytometric assay for lymphocyte HLA-B27 expression using a two-color direct immunofluorescent assay was compared to traditional microlymphocytotoxicity testing on 209 clinical samples. For the flow cytometric assay, whole blood was mixed with a monoclonal anti-B27 conjugated to fluorescein-isothiocyanate (FITC) and anti-CD3 conjugated to phycoerythrin (PE). The samples were analyzed with flow cytometry by gating on CD3 positive events and anti-B27 staining intensity was evaluated as median channel fluorescence of the histogram peak. The median channel fluorescence was least with B27 negative and B7 negative samples (84 +/- 17), intermediate with samples that were B27 negative but B7 positive (118 +/- 13), and greatest with samples that were B27 positive (155 +/- 13). In addition to cross-reactivity with the B7 antigen (n = 38), the monoclonal anti-B27 cross-reacted with HLA-B37 positive samples (n = 3) and HLA-B39 positive samples (n = 3). Using a median channel fluorescence cutoff of 136, 39 of the 40 B27 positive samples gave positive results in the flow cytometric assay for a sensitivity of 97.6%. The specificity was 95.9% with 7 false positives of 169 B27 negative samples. The flow cytometric HLA-B27 assay is a convenient, useful screening test. For greatest specificity, samples positive by flow cytometry should be confirmed by conventional microlymphocytotoxicity or by use of other monoclonal antibodies directed against B27.

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Flow CytometryFluorescent Antibody Technique, DirectHLA-B27 AntigenHumansImmunophenotypingMass ScreeningReference ValuesJournal Article

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BibTeXRIS

B Lingenfelter, T C Fuller, L Hartung, J Hunter, C Wittwer. 1995-06-15. HLA-B27 screening by flow cytometry.. https://doi.org/10.1002/cyto.990220211

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