Reconstitution of NK cells after haploidentical SCT. (A) FACS analysis of CD3⁺, CD19⁺, and CD3^-CD56⁺ cells in peripheral blood (PB) from 2 donor and patient pairs (no. 8, no. 10). PB from donors was collected before SCT and from patients at engraftment to the fourth or sixth month after SCT. Cells were analyzed on lymphocyte gates. T (♦), B (▪), and NK (▵) cell contents are expressed as a percentage of CD45⁺ lymphocytes. (B) Absolute counts of CD3^-CD56⁺ NK cells in PB of the same pairs. Days after transplantation are indicated.