Figure 6.

B7–1 and/or B7–2 on host cells were required for optimal T cell division in vivo. (A) The amount of Vα8⁺ T cells recovered from the spleen, the percentages of the P1CTL recovered were given in the panel. (B) Distributions of CFSE intensities among the Vα8⁺ T cells. Naive P1CTL were labeled with CFSE and adoptively transferred into the RAG-2^−/− J558-B7H tumor-bearing mice that had received either control (a mixture of rat and hamster) IgG or anti–B7–1 and B7–2 mAbs on days 0, 1, and 2 of T cell adoptive transfer. Spleen cells were harvested and analyzed on day 3 of the adoptive transfer. This experiment was repeated twice with similar results.