Flow cytometric analysis of murine CD4, murine MHC-I (H2Kd), murine CD8, human CD4 and HLA-DR3 from day 2–61 after transplantation. MuCD4 (a,b), H-2Kd (c), CD8 (d), huCD4 (e), and HLA-DR (f) levels from peripheral blood (gated for lymphocytes) from days 2–61 after co-transplantation of allogeneic bone marrow and allogeneic splenocytes. Results are shown in comparison to transplantation of syngeneic bone marrow cells