SR1 CD7⁺ cells home to the thymus in vivo and have comparable homing capabilities to naive CD7⁺ cells. (A) Thymuses of SR1 CD7⁺ cell–injected mice were harvested after 4 weeks, and the percentage of live CD45⁺ cells and CD4 and CD8 are shown (n = 4). (B) A 1:1 mixture of flow cytometrically sorted ZsGreen⁺ naive CD7⁺ cells (3.0 × 10⁵) and ZsGreen⁻ (3.0 × 10⁵) SR1 CD7⁺ cells were injected into nonirradiated NSG neonatal mice, and the thymuses were harvested and analyzed after 4 weeks (n = 3 mice for naive alone or naive plus SR1; n = 4 mice for SR1 alone). Flow cytometric analysis of human CD45 and ZsGreen cell surface expression on DAPI-negative (DAPI⁻) CD45⁺–gated cells. CD4 and CD8 expression are shown on CD45⁺ZsGreen⁺- and CD45⁺ZsGreen⁻-gated cells for naive CD7⁺ or SR1 CD7⁺–derived cells, respectively. (C) Percentage of ZsGreen⁻ or ZsGreen⁺ cells as a proportion of total human CD45⁺ cells within the thymus for individual mice is shown. (D) Thymic cellularity for ZsGreen⁻ or ZsGreen⁺ cells in transplanted mice, with error bars corresponding to standard error of the mean.