Absence of donor chimerism in central and peripheral lymphoid compartments of B6-cdd recipients.

TNFR1^−/− marrow was transplanted into B6-cdd (Ly9.1⁻) naive and primed recipients 1 day after 9.0 Gy TBI. Thymus, bone marrow, and spleen cells were analyzed 14 days later. Ly9.1 (clone 30C7) staining identifies expression (Ly9.1) on most thymocytes, peripheral T and B cells, bone marrow, lymphoid cells, and hematopoietic progenitors of the C3H.SW strain but not C57BL/6 (Ly9.1⁻). B6-cdd naive recipients contained 24.2%, 23.3%, and 68.9% donor positive in the thymus, bone marrow, and spleen, respectively, whereas primed B6-cdd recipients demonstrated an absence of donor cells in all compartments tested. M1 indicates channel marker.