Figure 2.

Impact of donor NK cells during allogeneic HCT. Host licensed NK cells are responsible for HSC rejection minimizing donor HSC engraftment. Donor NK cells, in contrast, are known to be tolerant to donor HSC and play a fundamental role in the reduction of GvHD by the elimination of alloreactive T cells. Donor unlicensed NK cells, in HLA-matched HCT, and licensed NK cells, in HLA-mismatched (haploidentical) HCT, can additionally provide stronger antitumor responses due to the lack of recognition of HLA in tumor cells (missing ligand).