Allogeneic CLP cotransplantation protects thymus-bearing hosts from lethal MCMV disease. (A) Thymus-bearing mice received transplants of 500 LT-HSCs alone (•; n = 30, 23% survival) or 500 LT-HSCs and 3000 CLPs (○; n = 28, 64% survival). *P < .0001 (• versus ○). (B) Mean splenic CD4⁺ and CD8⁺ count on day 35 after CLP cotransplantation in uninfected mice (–MCMV) (n = 9) or in surviving mice after MCMV infection (+MCMV) (n = 4). ▦ indicates percentages of CLP-derived cells; and •, non-CLP-derived cells (host- and HSC-derived). (C) Absolute blood lymphocyte counts on day 35 after CLP cotransplantation in uninfected mice (–MCMV) (n = 9) or in surviving mice after MCMV infection (n = 8). The dotted line indicates the lower normal limit. Mean ± SD. *P = .01.