“Incidence and significance of donor-specific antibodies in haploidentical stem cell transplantation”

PGF is a devastating complication after allogeneic transplant. We retrospectively analyzed our haploidentical transplant registry to report the incidence and impact of DSA and anti-HLA on engraftment. 107 patients were identified. Median recipient-age of 22, median donor-age of 31. Sixty-two patients had AML (58%), 29 had ALL (27%), 16 (15%) had other malignancies. Sixty-one recipients (57%) had positive anti-HLA, 56 of them had the DSA results available, of these 17 patients had DSAs (15% of the total number of patients, or 28% of patients who have anti-HLA antibodies). The median cumulative MFI was 2062. Sixty-three percent of the DSA were against class-II HLA antigens. The OS, CIR, aGvHD, and cGvHD did not differ between patients with and without anti-HLA antibodies, nor between patients with and without DSA. The gender of the recipient and donor, as well as the gender mismatch between recipient and donor, were statistically associated with the incidence of anti-HLA antibodies. Three patients only developed GF (2.8%), one was primary (0.9%) and the other two secondary GF (1.9%). None of the GF cases was in patients with anti-HLA antibodies or DSA. The presence of anti-HLA or DSAs did not affect the outcomes including the incidence of PGF.