Persistence of recipient human leucocyte antigen (HLA) antibodies and production of donor HLA antibodies following reduced intensity allogeneic haematopoietic stem cell transplantation

• DOI: 10.1111/bjh.12890
• Publication Date: 2014-04-19T09:25:07Z
• Authors: Ross M. Fasano; Ewelina Mamcarz; Sharon Adams; Theresa Donohue J...; Kyoko Sugimoto; Xin Tian; Willy A. Flegel; Richard W. Childs
• Keywords: Isoantibodies

Summary The effects of reduced intensity conditioning (RIC) on human leucocyte antigen (HLA)‐alloimmunization and platelet transfusion refractoriness (PTR) following allogeneic haematopoietic stem cell transplantation (Allo‐HSCT) are unknown. We studied HLA‐alloantibodies in a cohort 16 patients (eight HLA‐alloimmunized with pre‐transplant histories PTR eight non‐alloimmunized controls) undergoing Allo‐HSCT using fludarabine/cyclophosphamide‐based RIC. Pre‐ post‐transplant serum samples were analysed for HLA‐antibodies compared to myeloid, T‐cell bone marrow plasma chimaerism. Among alloimmunized patients, the duration that persisted correlated strongly HLA‐antibody mean fluorescence (MFI) PRA levels (Spearman's rank correlation = 0·954 ( P 0·0048) 0·865 0·0083) respectively). Pre‐transplant MFI >10 000 was associated HLA antibody persistence >100 d 0·029). ≥100 3/8 despite recipient chimaerism being undetectable all lympho‐haematopoietic lineages including cells. Post‐transplant de‐novo developed three control two developing PTR; donors these demonstrated pre‐existing equivalent specificity those patient, confirming donor origin. These data show may persist prolonged periods Further study is needed determine incidence as consequence donor–derived alloimmunization before recommendations screening can be made.