CD84 MoAbs reactive with the protein product of the pHLy9-β cDNA. 300.19 cells transfected with HLy9-β cDNA were examined by using the CD84 MoAbs 2G7, 152-1D5, and 153-4D9 in indirect immunofluorescence assays with flow cytometry analysis. Fluorescence histograms generated using 300.19 transfected cells are shown as solid lines. Staining of the 300.19 untransfected cells are shown as dotted lines. A MoAb against CD22 (HB22.7) was unreactive with both transfected and untransfected cell lines. Fluorescence intensity is shown on a three-decade log scale.