Abo不相容性和抗a / B异凝集素滴度对血液恶性肿瘤清髓处理后输血需求和无关脐带血移植的早期结果的影响
Authors: Chen Yang , Wang Huiru , Sun Zimin , Yao Wen , Liu Huilan , Zhu Xiaoyu , Wang Dongyao 
Published: November 2020

Abstract Background:ABO incompatibility is not considered a main contraindication to allogeneic hematopoietic stem cell transplantation (aHSCT). However, it has been associated with a number of immunohematological complications. The effects of ABO incompatibility on aHSCT remain controversial.The change of isoagglutinin titers and early clinical outcomes were analyzed after unrelated cord blood transplantation (UCBT) with ABO-incompatibility donor.
Methods:252 patients with hematological malignant diseases and other hematological disorders who underwent unrelated UCBT from January 2019 to April 2020 were retrospectively analyzed in this research. Patients were studied in identical, major, minor and bidirectional mismatch groups. Immunoglobulin m (IgM) isoagglutinin titers were tested one day before the transplant (-1 day), 2 weeks post-transplant, 4 weeks post-transplant and 6 weeks post-transplant.
R esults:76 match,71 major mismatch, 70 minor mismatch and 35 bidirectional unrelated UCBT were identified. The median neutrophil, PLT and red blood cell (RBC) recovery days were 18, 38 and 22, respectively. ABO mismatch did not influence the neutrophil, PLT and RBC engraftment. The median of RBC transfusion in 30 days were 5 units and PLT were 6 units. There were no statisitcal difference in 0-30 days RBC and PLT transfusion after UCBT. 31-100 days transfusion was similar to in 30 days transfusion. No patients developed pure red cell anemia (PRCA). -1day IgM titers ≥1:16 did not develop higher risk of grade II-IV aGVHD when compared with titers≤1:8 group. However, we detected a marginal higher PLT transfusion in 30 days after transplant at antibody titers ≥1:16 group when compared with titers≤1:8 (P=0.051). In the major and bidirectional groups, we found that group O IgM anti-donor antibodies were displayed a significant higher than the group B anti-A titer (p&lt;0.001) in setting the time one day before the transplant, but no significant with group A. 2 weeks after the transplant, group B anti-A was still showed significant lower than the group O anti-A (p&lt;0.001). 4 weeks after the UCBT, we observed a modest, but no statistical significant lower titers of group B anti-A antibodies as compared with O group (P=0.097). 6 weeks after the transplant, there were no statistical significant among group O, A and B. In the multivariable Cox regression model, transfusion of ≥5 RBC units in 30 days after UCBT (HR=1.727, 95%CI=1.020-2.926, P=0.042) and PLT engraftment ≥38 days (HR=1.964, 95%CI=1.134-3.401, P=0.016) were correlated to greater risk of grade severe aGVHD.
Conclusion:This study showed that ABO mismatch did not influence the neutrophil, PLT and RBC recovery time.Group O IgM anti-donor isoagglutinins in recepients showed a higher titers than the group B in setting with the time (-1 days pre-transplant, 2 weeks post-transplant, 4 weeks post-transpant). Pre-transplant higher anti-donor isoagglutinins were associated with more PLT transfusion requirements after UCBT. More RBC transfusion (≥5 units) and longer PLT recovery time (≥38 days) showed a higher incidence of severe aGVHD.

Disclosures
No relevant conflicts of interest to declare.