Effect of Delta4 on B-cell and T-cell development.

Expression of Delta4 impairs B-cell development and leads to occurrence of CD4⁺CD8⁺ T cells in the peripheral blood. White blood cells were isolated and stained with fluorochrome-conjugated antibodies to CD4, CD8, CD3, B220, immunoglobulin D (IgD), Mac1, Gr-1, and CD45.1. (A) Representative FACS contour blots and histograms are shown for staining of WBC cells from one Delta4-transduced and one control mouse 15 weeks after bone marrow transplantation. The numbers indicate the percentage of cells within each quadrant. (B) The average number of positive cells for the cell populations indicated is shown for Delta4-transduced and control mice at week 5 (MSCVpac, n = 5; MSCVpac-Delta4, n = 5) and 15 (MSCVpac, n = 4; MigR, n = 2; MSCVpacDelta4, n = 2; MigRDelta4, n = 2) after BMT. Error bars represent the SD.