Myeloablative conditioning promotes reconstitution by semiallogeneic BM progenitors after intravenous or intrathymic administration. ZAP-70−/− mice were preconditioned with busulphan and cyclophosphamide before transplantation with semiallogeneic lineage-negative BM progenitor cells (2 × 105) isolated from C57Bl/6JxCBA/J WT mice. Progenitors were administered by either intravenous or intrathymic routes and were sacrificed 28 weeks posttransplantation. (A) Bar graph quantification of the percentages of CD45.1+ donor cells detected in the thymi of intravenous- and intrathymic-reconstituted ZAP-70−/− mice 28 weeks posttransplantation (mean ± SD). (B) Representative dot plots showing the CD4/CD8 phenotypes of donor cells in the thymi of intravenous- and intrathymic-reconstituted ZAP-70−/− mice compared with donor and recipient mice. (C) Bar graph quantification of the percentages of CD45.1+ donor cells in the lymph nodes of intravenous- and intrathymic-reconstituted mice (mean ± SD; * P < .05). (D) Dot plots showing the CD3/CD19 phenotypes of donor cells in the lymph nodes of intravenous- and intrathymic-reconstituted mice compared with donor and recipient controls (upper panels). The proportion of donor-derived B cells in the LN of intravenous- and intrathymic-reconstituted mice was monitored as a function of CD45.1 expression (lower panels). The percentages of CD45.1+ cells are indicated, and data are representative of 3 independent experiments.
