Thymectomized hosts are protected from lethal MCMV disease after allogeneic CLP cotransplantation. (A) Thymus-bearing (TB; ○;n = 28, 64% survival) or thymectomized (TXO; □;n = 13, 54% survival) mice received transplants of 500 LT-HSCs and 3000 CLPs and compared with thymus-bearing mice that received transplants of 500 LT-HSCs alone (•;n = 30, 23% survival). P = NS (○ versus □). (B) FACS analysis of spleen on day 35 following CLP cotransplantation. (C) Absolute blood lymphocyte counts (mean ± SD) on day 35 in thymus-bearing (n = 8) and thymectomized (n = 7) mice that received CLP cotransplants and survived MCMV infection. P = NS. (D) CD4⁺ and CD8⁺ count in blood (mean ± SD) on day 35 in thymectomized mice that received CLP cotransplants that survived MCMV infection (n = 7). ▦ indicates percentages of CLP-derived cells; and •, non-CLP-derived cells.