Expression pattern of mB7-H1.

(A) Tissue distribution of mB7-H1 mRNA in mouse tissue dot blot (Clontech). The random-primed cDNA probe containing the full length of mB7-H1 cDNA was prepared and labeled using ³²P-dCTP. The tissues corresponding to the dot are indicated in the right panel. (B) Expression of mB7-H1 on resting and activated T cells. NW-purified T cells were analyzed without (control) or with stimulation of Con A, anti-CD3, or anti-CD3 plus anti-CD28 for 48 hours. The cells were stained by FITC-conjugated mAb against CD3 and rabbit anti–B7-H1 antibodies (solid line) or control immunoglobulin (dotted line) followed by PE-conjugated goat antirabbit IgG. Positive cells for CD3 were gated and analyzed for the expression of mB7-H1 by FACS. (C) Expression of mB7-H1 on B cells and macrophages. Freshly isolated mouse splenocytes were analyzed without (upper panel) or with stimulation (Activated; lower left panel) by LPS for 48 hours. Macrophages obtained from the peritoneal cavity of B6 mice were stimulated with LPS and IFN-γ (lower right panel). The cells were doubly stained by FITC-conjugated mAb against B220 or Mac-1 and rabbit anti–B7-H1 antibodies (solid line) or control immunoglobulin (dotted line) followed by PE-conjugated goat antirabbit IgG. Positive cells for B220 or Mac-1 were gated and analyzed for the expression of mB7-H1 by FACS. The percentages of B7-H1⁺ cells in the gated fraction are indicated in each histogram.