Donor-type red blood cell transfusion to deplete isoagglutinins prior to allogeneic stem cell transplantation from ABO major incompatible bone marrow donors

ABO incompatibility affects approximately 40% of allogeneic stem cell transplants in Caucasian patient populations. Because bone marrow (BM), the preferred graft from paediatric sibling donors and for non-malignant diseases, has a red blood cell (RBC) content similar to blood, anti-donor isoagglutinins must either be depleted from the recipient or RBCs removed from the graft. To achieve tolerability of unmanipulated BM grafts, we used controlled infusions of donor ABO-type RBC units to deplete isoagglutinins before the transplant. This retrospective study evaluates the outcomes of 52 ABO major incompatible BM transplants performed at our centre between 2007 and 2019. The use of donor-type RBC transfusions was well tolerated. They effectively reduced isoagglutinins levels, typically achieving target titres after one (60%) or two (29%) transfusions. The approach allowed for successful and uneventful infusions of unmanipulated BM which provided timely engraftment. The transplant outcomes were not inferior to those of a matched-pair control group of patients with ABO-identical donors.

Treatment for pure red cell aplasia after major ABO-incompatible allogeneic stem cell transplantation: a multicentre study

Pure red cell aplasia (PRCA) following allogeneic haematopoietic stem cell transplantation (aHSCT) with major ABO incompatibility is responsible for transfusion dependent anaemia, impaired quality of life and iron overload. We conducted a retrospective study, over a 10-year period, which included all consecutive patients who received a major ABO mismatched aHSCT, to assess the impact of specific treatment on PRCA. We did not observe any PRCA in the 57 aHSCT issued from cord blood. Among the remaining 631 patients, cumulative incidence of PRCA was 10·5% [range 8·2-13.0]. The median duration of resolved PRCA was 171 days [IQR 116; 261]. Pre-transplant high isohaemagglutinins titre was associated with an increased risk of PRCA (P < 10^-4 ). PRCA did not affect overall survival (P = 0·95). Twenty-two patients (33·3%) received at least one specific treatment. The most commonly used treatments were rituximab (17 patients) and donor lymphocyte infusion (DLI; seven patients). Regarding PRCA resolution, we did not observe a significant difference between treated or untreated subjects (HR = 0·93, 95% confidence interval (CI) 0·48- 1·80; P = 0·82). Similar results were observed with erythropoietin treatment (22 patients, HR = 0·86 95% CI: [0·47-1·57] P = 0·62). Our data do not support the use of erythropoietin, rituximab or DLI for the treatment of PRCA.

Transfusing maternal blood to her newborn baby-irrespective of ABO mismatch

Background: Though blood transfusions are the common procedures in pediatric patients, transfusion reactions are rare in children. Though in adults, uncross-matched ABO group-specific blood is used in emergencies, there are no such reports in neonates and children. There are stray case reports about transfusing maternal blood for her baby and maternal blood is de facto compatible regardless of an ABO mismatchObjective: Confirming our previous hypothesis that maternal blood is compatible with her baby's blood; and maternal blood can be used for transfusion in her newborn baby irrespective of ABO match/ mismatch.Design: Prospective interventional study.Setting and Participants: Fifty-one mother-baby pairs were recruited attending Pediatric Unit of our Community Hospital from 15 July 2013 to 13 July 2015. After obtaining consent from the parents, all the required lab tests were done. Since all lab reports were favourable; these babies qualified for transfusion of maternal blood.Interventions: Fifty-one sick newborns were transfused fresh whole maternal blood as a part of treatment; irrespective of mother-baby ABO match or mismatch.Results: All babies tolerated maternal blood well and showed significant and rapid improvement. Minimum period of observation was from a minimum of 32 to a maximum of 56 months. All the babies showed good growth and development.Conclusion: By observing a particular protocol and procedural techniques, mother's blood may be used for transfusion in her own baby in neonatal period, irrespective of ABO mismatch.Significance: This is probably the largest series in world literature of 51 newborns being transfused maternal blood either ABO match or mismatch.

Nonmyeloablative Stem Cell Transplantation with Alemtuzumab/Low-Dose Irradiation to Cure and Improve the Quality of Life of Adults with Sickle Cell Disease

Allogeneic hematopoietic stem cell transplantation (HSCT) is rarely performed in adult patients with sickle cell disease (SCD). We utilized the chemotherapy-free, alemtuzumab/total body irradiation 300 cGy regimen with sirolimus as post-transplantation immunosuppression in 13 high-risk SCD adult patients between November 2011 and June 2014. Patients received matched related donor (MRD) granulocyte colony-stimulating factor-mobilized peripheral blood stem cells, including 2 cases that were ABO incompatible. Quality-of-life (QoL) measurements were performed at different time points after HSCT. All 13 patients initially engrafted. A stable mixed donor/recipient chimerism was maintained in 12 patients (92%), whereas 1 patient not compliant with sirolimus experienced secondary graft failure. With a median follow-up of 22 months (range, 12 to 44 months) there was no mortality, no acute or chronic graft-versus-host disease (GVHD), and no grades 3 or 4 extramedullary toxicities. At 1 year after transplantation, patients with stable donor chimerism have normalized hemoglobin concentrations and improved cardiopulmonary and QoL parameters including bodily pain, general health, and vitality. In 4 patients, sirolimus was stopped without rejection or SCD-related complications. These results underscore the successful use of a chemotherapy-free regimen in MRD HSCT for high-risk adult SCD patients and demonstrates a high cure rate, absence of GVHD or mortality, and improvement in QoL including the applicability of this regimen in ABO mismatched cases (NCT number 01499888).

ABO mismatch is associated with increased nonrelapse mortality after allogeneic hematopoietic cell transplantation

We evaluated ABO associated outcomes in 1737 patients who underwent allogeneic hematopoietic cell transplantation (allo-HCT) at Stanford University between January 1986 and July 2011. Grafts were 61% ABO matched, 18% major mismatched (MM), 17% minor MM, and 4% bidirectional MM. Median follow-up was 6 years. In multivariate analysis, overall survival (OS) was inferior in minor MM hematopoietic cell transplantations (median 2.1 versus 6.3 years; hazard ratio [HR], 1.56; 95% confidence interval [CI], 1.19 to 2.05; P = .001) in comparison with ABO-matched grafts. ABO minor MM was associated with an increase in early nonrelapse mortality (NRM) (18% versus 13%; HR, 1.48; 95% CI, 1.06 to 2.06; P = .02). In an independent Center for International Blood and Marrow Transplant Research (CIBMTR) analysis of 435 lymphoma patients receiving mobilized peripheral blood grafts, impairment of OS (HR, 1.55; 95% CI, 1.07 to 2.25; P = .021) and increased NRM (HR, 1.72; 95% CI, 1.11 to 2.68; P = .03) were observed in recipients of ABO minor-MM grafts. A second independent analysis of a CIBMTR data set including 5179 patients with acute myeloid leukemia and myelodysplastic syndrome identified a nonsignificant trend toward decreased OS in recipients of ABO minor-MM grafts and also found ABO major MM to be significantly associated with decreased OS (HR, 1.19; 95% CI, 1.08 to 1.31; P < .001) and increased NRM (HR, 1.23; 95% CI, 1.08 to 1.4; P = .002). ABO minor and major MM are risk factors for worse transplantation outcomes, although the associated hazards may not be uniform across different transplantation populations. Further study is warranted to determine which patient populations are at greatest risk, and whether this risk can be modified by anti-B cell therapy or other peri-transplantation treatments.