Effect of IL-7 following T-cell–replete transplantation. Recovery of CD45.1⁺/CD19⁺ (recipient) and CD45.2⁺/CD19⁺ (donor) B-cell numbers was evaluated in recipients of T-cell–replete BMT followed by treatment with IL-7 at a dose of 2500 ng twice daily (▵,n = 5), IL-7 at a dose of 500 ng twice daily (▪,n = 9), or PBS (▴,n = 9). P values shown correspond to both the comparison of 2500 ng IL-7 versus PBS and the comparison of 500 ng IL-7 versus PBS.