KGF broadens the TCR repertoire of CD8⁺ cells responding to vaccine in mice after allogeneic BMT. B6 mice underwent T cell–depleted BMT, were treated with KGF, and were vaccinated as described in Figure 5. On day 40, CD8⁺tetramer⁺ cells from spleens were evaluated for TCR Vβ family origin with the use of flow cytometry (A). Shaded in gray is the background Vβ family usage, determined by the 20% trimmed mean of tetramer⁻ cells from the same experiments. The number of Vβ families used by tetramer⁺ cells from individual mice, defined as usage above background, is also shown (B, *P = .01). Data are pooled from 2 experiments with similar results.