Figure 1.

Thymus engraftment by in vitro-generated progenitor T cells in unmanipulated young and old mice. (A) CD25⁺ DsRed⁺ donor proT cells per 10⁷ host thymocytes (top) and splenocytes (bottom) isolated from host thymuses and spleens of non-irradiated aged and young mice. Each group of mice (n=4-5) were injected with 1, 3, or 9 x10⁶ proT cells. Error bars depict SEM; *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001 analyzed by two-way ANOVA. (B) Representative flow cytometric analysis of detected DsRed⁺ proT cells from the thymus of a host mouse (top). Aggregated percentages of DsRed⁺ proT cells in blood vessels out of total DsRed⁺ proT cells from host thymuses injected with either 1, 3, or 9 x10⁶ proT cells (bottom). Hosts were intravenously injected with CD45-AF700 antibodies 3 minutes prior to sacrificing. Error bars depict SEM; difference between the aged and young mice groups was not significantly (ns) different as analyzed by two tailed unpaired student’s t-test.