Lymphocyte subsets at latest follow-up (>1 year posttransplant). CD3⁺ cells (A), CD8⁺ cells (C), and CD19⁺ (D) cells were comparable between patients with MHC class II deficiency (n = 14) and controls. (B) CD4⁺ cells were significantly lower in patients with MHC class II deficiency compared with controls (P = .01). (E) There was no significant difference in CD4⁺ cells before and after transplant in patients with MHC class II deficiency. (F) Pre- and posttransplant CD4⁺ cells in individual patients and controls.