DataSheet_1_Results of haploidentical transplant in patients with donor-specific antibodies: a survey on behalf of the Spanish Group of Hematopoietic Transplant and Cell Therapy.docx

BackgroundDonor-specific antibodies (DSAs) are IgG allo-antibodies against mismatched donor HLA molecules and can cause graft failure (GF) in the setting of haploidentical hematopoietic stem cell transplantation (haplo-HSCT). Our aim was to report the experience of the Spanish Group of Hematopoietic Transplant (GETH-TC) in DSA-positive patients who had undergone haplo-HSCT.MethodsWe conducted a survey of patients who underwent haplo-HSCT in GETH-TC centers between 2012 and 2021. Data were collected on the DSA assay used, monitoring strategy, complement fixation, criteria for desensitization, desensitization strategies and transplant outcomes.ResultsFifteen centers from the GETH-TC responded to the survey. During the study period, 1,454 patients underwent haplo-HSCT. Seventy of the transplants were performed in 69 DSA-positive patients, all of whom lacked a suitable alternative donor; 61 (88%) patients were female (90% with prior pregnancies). All patients received post-transplant cyclophosphamide-based graft-versus-host disease prophylaxis. Regarding baseline DSA intensity, 46 (67%) patients presented mean fluorescence intensity (MFI) >5,000, including 21 (30%) with MFI >10,000 and three (4%) with MFI >20,000. Six patients did not receive desensitization treatment, four of them with MFI 20,000 as an independent risk factor for survival and an increase in titers after infusion as an independent risk factor for GF.ConclusionsHaplo-HSCT is feasible in DSA-positive patients, with high rates of engraftment after desensitization guided by DSA intensity. Baseline MFI >20,000 and increased intensity after infusion are risk factors for survival and GF.

背景：针对不匹配供体HLA分子的IgG同种异型抗体，即供体特异性抗体（DSAs），可导致半相合造血干细胞移植（haplo-HSCT）后移植物功能衰竭（GF）。本研究旨在报告西班牙造血移植组（GETH-TC）在DSA阳性患者中进行的半相合造血干细胞移植的实践经验。
方法：我们对2012年至2021年间在GETH-TC中心接受半相合造血干细胞移植的患者进行了调查。收集了关于DSA检测方法、监测策略、补体固定、脱敏标准、脱敏策略和移植结果的数据。
结果：GETH-TC的15个中心对调查做出了回应。在研究期间，1,454名患者接受了半相合造血干细胞移植。其中70例移植是在69名DSA阳性患者中进行的，这些患者均缺乏合适的替代供体；61名（88%）患者为女性（其中90%有既往妊娠史）。所有患者都接受了基于环磷酰胺的移植物抗宿主病预防治疗。关于基线DSA强度，46名（67%）患者的平均荧光强度（MFI）>5,000，包括21名（30%）MFI >10,000和3名（4%）MFI >20,000的患者。6名患者未接受脱敏治疗，其中4名患者的MFI为20,000，作为生存独立的危险因素，以及输注后滴度增加作为移植物功能衰竭独立的危险因素。
结论：在DSA阳性患者中，半相合造血干细胞移植是可行的，DSA强度指导下的脱敏治疗后的植入成功率较高。基线MFI >20,000和输注后强度增加是生存和移植物功能衰竭的危险因素。