A phenotypically CD8 positive subset of human B cells.

Mobilized apheresis material was analyzed with multicolor flow cytometry. The CD8+ TCR negative population was gated (A), and the cells included in the thick black gate resolved using the markers CD335 for NK cells and CD19 for B cells (B). Percentage of both populations is given in the quadrants, and black arrows point to the CD8 expression profiles and MFI values of the boxed CD335+ NK cells and CD19+ B cells, respectively. One representative donor out of four shown. (C) TCR-negative cells were flow sorted into CD8 high, CD8 medium, and CD8 dim populations along with TCR-CD8- cells as negative controls, as indicated by the dashed boxes on panel (A). Expression of genes in the sorted population was then measured by quantitative real-time PCR, and is shown as percentage of the GAPDH housekeeping gene (* for NCR, encoding CD335, the scale on the right hand side applies). One representative donor out of two shown.