An update on ABO incompatible hematopoietic progenitor cell transplantation

The effect of increased collect pump rate on collection efficiency in hematopoietic progenitor cell collection by apheresis in allogeneic adult donors-A single center analysis

BACKGROUND

Optimizing CD34 recovery while minimizing harm to hematopoietic progenitor cell donors by apheresis (HPC(A) donors) is critical to the success of allogeneic hematopoietic cell transplantation. We examined the efficacy and safety of starting allogeneic HPC(A) donors at a collect pump rate (CPR) of 2 mL/min on the Spectra Optia regardless of the inlet flow rate and/or pre-apheresis white blood cell (WBC) count (high CPR group).

STUDY DESIGN AND METHODS

A single-center retrospective study was performed on allogeneic adult donors from 10/2020 to 12/2022. From 10/2020 to 6/19/2022, all donors had CPR of ~1 mL/min (historical group). High CPR group started 6/20/2022.

RESULTS

During the study period, 412 donors were in historical group versus 196 (32.2%) in high CPR group. Median CD34 collection efficiency (CE) was higher and more consistent in high CPR group (55.1% vs. 53% in historical group, p < .0001) and remained significant in multivariate analysis. Although product volume was higher in high CPR group, WBC, hematocrit, and platelet concentrations were significantly lower. No difference in engraftment outcomes in patients receiving products from two groups was observed. Moreover, no differences occurred in a significant peri-procedural adverse event or percent decrease in platelets (6.87% decrease in platelets per 100 × 106 CD34 cells collected versus 6.66% in historical group, p = .89). Furthermore, high CPR group had ~26 min less in collection time for every 100 × 106 CD34 cells collected, resulting in less positive fluid balances.

CONCLUSIONS

Starting allogeneic HPC(A) donor collection at a CPR of 2 mL/min is safe and effective.

Optimizing a fully automated and closed system process for red blood cell reduction of human bone marrow products

BACKGROUND AIMS

Hematopoietic stem cell transplantation using bone marrow as the graft source is a common treatment for hematopoietic malignancies and disorders. For allogeneic transplants, processing of bone marrow requires the depletion of ABO-mismatched red blood cells (RBCs) to avoid transfusion reactions. Here the authors tested the use of an automated closed system for depleting RBCs from bone marrow and compared the results to a semi-automated platform that is more commonly used in transplant centers today. The authors found that fully automated processing using the Sepax instrument (Cytiva, Marlborough, MA, USA) resulted in depletion of RBCs and total mononuclear cell recovery that were comparable to that achieved with the COBE 2991 (Terumo BCT, Lakewood, CO, USA) semi-automated process.

METHODS

The authors optimized the fully automated and closed Sepax SmartRedux (Cytiva) protocol. Three reduction folds (10×, 12× and 15×) were tested on the Sepax. Each run was compared with the standard processing performed in the authors' center on the COBE 2991. Given that bone marrow is difficult to acquire for these purposes, the authors opted to create a surrogate that is more easily obtainable, which consisted of cryopreserved peripheral blood stem cells that were thawed and mixed with RBCs and supplemented with Plasma-Lyte A (Baxter, Deerfield, IL, USA) and 4% human serum albumin (Baxalta, Westlake Village, CA, USA). This "bone marrow-like" product was split into two starting products of approximately 600 mL, and these were loaded onto the COBE and Sepax for direct comparison testing. Samples were taken from the final products for cell counts and flow cytometry. The authors also tested a 10× Sepax reduction using human bone marrow supplemented with human liquid plasma and RBCs.

RESULTS

RBC reduction increased as the Sepax reduction rate increased, with an average of 86.06% (range of 70.85-96.39%) in the 10×, 98.80% (range of 98.1-99.5%) in the 12× and 98.89% (range of 98.80-98.89%) in the 15×. The reduction rate on the COBE ranged an average of 69.0-93.15%. However, white blood cell (WBC) recovery decreased as the Sepax reduction rate increased, with an average of 47.65% (range of 38.9-62.35%) in the 10×, 14.56% (range of 14.34-14.78%) in the 12× and 27.97% (range of 24.7-31.23%) in the 15×. COBE WBC recovery ranged an average of 53.17-76.12%. Testing a supplemented human bone marrow sample using a 10× Sepax reduction resulted in an average RBC reduction of 84.22% (range of 84.0-84.36%) and WBC recovery of 43.37% (range of 37.48-49.26%). Flow cytometry analysis also showed that 10× Sepax reduction resulted in higher purity and better recovery of CD34+, CD3+ and CD19+ cells compared with 12× and 15× reduction. Therefore, a 10× reduction rate was selected for the Sepax process.

CONCLUSIONS

The fully automated and closed SmartRedux program on the Sepax was shown to be effective at reducing RBCs from "bone marrow-like" products and a supplemented bone marrow product using a 10× reduction rate.

[ABO incompatibility and complications in hematopoietic stem cell transplantation]

Background

Hematopoietic stem cell transplants (HSCT) can be performed regardless of the ABO group compatibility between donor and recipient. ABO incompatibility in HSCT is related to pure red cell aplasia (PRCA), or passenger lymphocyte syndrome. The impact of ABO incompatibility on graft-versus-host disease and transplant-related mortality is controversial due to the heterogeneity of procedures carried out in different transplant centers.

Objective

To determine the prevalence of ABO incompatibility and its complications in a hematopoietic stem transplant unit.

Material and methods

An observational, retrospective study was carried out in patients undergoing HSCT from January 2014 to January 2020. All trasplant patients were included. Qualitative variables were analyzed using chi-squared test, and Wilcoxon and Student's t tests were used for quantitative variables. A p < 0.05 was considered significant.

Results

124 patients undergoing HSCT were analyzed, out of which 31 had ABO incompatibility, with a punctual prevalence of 24.4%; among them, 54% presented with major incompatibility, 32% minor incompatibility and 13% bidirectional incompatibility. Three cases of PRCA were reported. There were no differences in survival at one year in both groups.

Conclusions

The ABO incompatibility ant its complications were not related to the increase in mortality. Randomized prospective studies are required to define the role of ABO incompatibility in HSCT prognosis.

ABO Mismatch in Allogeneic Hematopoietic Stem Cell Transplant: Effect on Short- and Long-term Outcomes

Supplemental Digital Content is available in the text.

Background.

The impact of ABO incompatibility (ABO-I) on hematopoietic stem cell transplant outcomes is still debated.

Methods.

We retrospectively investigated 432 consecutive transplants performed at our center (2012–2020). All patients but 6 were affected by hematologic malignancies. The effect of different ABO match combinations on engraftment rate, transfusion support, acute and chronic graft-versus-host disease incidences, nonrelapse mortality (NRM), disease-free survival, and overall survival was assessed in univariate and multivariate analysis. Significance was set at P < 0.05.

Results.

ABO match distribution among transplants was as follows: 223 ABO-compatible, 94 major ABO-I, 82 minor ABO-I, and 33 bidirectional ABO-I. At univariate analysis, major ABO-I delayed the engraftment of neutrophils, platelets, and erythroid cells. At multivariate analysis, major ABO-I transplants displayed delayed erythroid engraftment (odds ratio [OR], 0.51; 95% confidence intervals [CIs], 0.38-0.70; P < 0.0001) and hindered transfusion independence for both red blood cells (OR, 0.52; 95% CI, 0.37-0.72; P = 0.0001) and platelets (0.60; 95% CI, 0.45-0.86; P = 0.0048). Moreover, major ABO-I transplants received greater amounts of blood products (P < 0.0001 for red blood cells and P = 0.0447 for platelets). In comparison with other ABO matches, major ABO-I was associated with an increased NRM (OR, 1.67; 95% CI, 1.01-2.75; P = 0.0427). No effects of ABO-mismatch were found on graft-versus-host disease, disease-free survival, and overall survival.

Conclusions.

Major ABO mismatch delays multilineage engraftment hinders transfusion independence and increases NRM. The prognostic impact of transfusion burden in hematopoietic stem cell transplantation deserves to be explored.

Investigation of risk factors associated with erythrocyte engraftment after ABO-incompatible hematopoietic stem cell transplantation

ABO-incompatible hematopoietic stem cell transplantations (HSCTs) are widely practiced; however, the delay in erythrocyte engraftment can be problematic. While erythrocyte engraftment is usually indicated by an increase in reticulocyte levels without the need for erythrocyte transfusions, the disappearance of recipient-derived anti-A/B isoagglutinin and detection of donor-derived A/B antigens can also be used as other parameters. We conducted a retrospective analysis of 68 ABO-incompatible HSCTs, focusing on major and bidirectional mismatch. We analyzed known clinical risk factors associated with delayed erythrocyte engraftment using the three parameters (disappearance of anti-A/B isoagglutinin in recipient, detection of donor-derived A/B antigen, and reticulocyte levels >1%). Although the three parameters were well correlated, the results showed heterogeneity when analyzing the associated risk factors for delayed erythrocyte engraftment. In the analysis of all cases, the requirement for an HLA-matched platelet transfusion was a common risk factor. Furthermore, erythrocyte engraftment was slower in adults than in children. In adults, cytomegalovirus antigenemia was a risk factor for two parameters; however, in children, underlying disease was a common risk factor for all parameters. There is a complex relationship between erythrocyte engraftment and various factors related to HSCTs. Our results suggest that greater accuracy is possible by using analysis methods other than the measurement of reticulocyte levels.

Retrospective comparison between COBE SPECTRA and SPECTRA OPTIA apheresis systems for hematopoietic progenitor cells collection for autologous and allogeneic transplantation in a single center

INTRODUCTION

COBE SPECTRA [COBE] (Terumo, BCT Lakewood CO) apheresis system has been the most used device for hematopoietic progenitor cells (HPC) collection. Recently, it has been replaced by the SPECTRA OPTIA [OPTIA] (Terumo, BCT Lakewood CO) apheresis system. The aim of our study is to compare both methods for HPC collection.

MATERIAL AND METHODS

We retrospectively compared 302 HPC collection apheresis procedures (115 allogeneic donors and 187 autologous). The study cohort was divided according to the apheresis system used to analyze the differences between COBE and OPTIA, specifically efficacy of apheresis procedure and product characteristics.

RESULTS

OPTIA collections result in a higher CD34⁺ collection efficiency in both groups (autologous 45.3% vs 41%, P < .006; allogeneic 54.9% vs 45%, P < .0001). The total of CD34⁺ cells ×10⁶ /kg recipient collected in the product were comparable in both groups (autologous 2.9 in OPTIA group vs 2.8 in COBE group, P = .344; allogeneic 6.2 in OPTIA group vs 5.8 in COBE group, P = .186). The percentage of platelet loss in autologous donors was significantly lower (35.7% vs 40.8%, P < .01). Regarding quality of the product, we observed a significantly lower hematocrit in products collected with OPTIA in both groups (1.8% vs 4%, P < .0001) as well as significantly lower amount of leukocytes (median 153.4 vs 237.2 × 10⁹ /L in autologous, P < .0001; 239.5 vs 340.2 × 10⁹ /L in allogeneic P < .0001).

CONCLUSION

Both apheresis systems are comparable in collection of hematopoietic progenitor cells, with significantly higher collection efficiency with the OPTIA system. Collection products obtained with OPTIA contain significantly lower hematocrit and leukocytes.

ABO incompatibile graft management in pediatric transplantation

Up to 40% of donor-recipient pairs in SCT have some degree of ABO incompatibility, which may cause severe complications. The aim of this study was to describe available options and survey current practices by means of a questionnaire circulated within the EBMT Pediatric Diseases Working Party investigators. Major ABO incompatibility (donor's RBCs have antigens missing on the recipient's cell surface, towards which the recipient has circulating isohemagglutinins) requires most frequently an intervention in case of bone marrow grafts, as immediate or delayed hemolysis, delayed erythropoiesis and pure red cell aplasia may occur. RBC depletion from the graft (82%), recipient plasma-exchange (14%) were the most common practices, according to the survey. Graft manipulation is rarely needed in mobilized peripheral blood grafts. In case of minor incompatible grafts (donor has isohemagglutinins directed against recipient RBC antigens), isohemagglutinin depletion from the graft by plasma reduction/centrifugation may be considered, but acute tolerability of minor incompatible grafts is rarely an issue. According to the survey, minor ABO incompatibility was either managed by means of plasma removal from the graft, especially when isohemagglutinin titer was above a certain threshold, or led to no intervention at all (41%). Advantages and disadvantages of each method are discussed.

The Roles of Nurses in Hematopoietic Cell Transplantation for the Treatment of Leukemia in Older Adults

OBJECTIVE

To review and summarize nurses' roles in the care of the older adult undergoing an allogeneic hematopoietic cell transplant (HCT) for the treatment of leukemia.

DATA SOURCES

Published literature indexed in PubMed, CINAHL, textbooks, and clinical expertise.

CONCLUSION

Nurses are a vital component of the highly specialized care delivered before, during, and after an allogeneic HCT.

IMPLICATIONS FOR NURSING PRACTICE

Nurses who are prepared for the complex HCT care trajectory will be able to optimally meet the complex needs of the older adult patient and their caregiver(s).

A comparison of two protocols for optimal red blood cell depletion using Sepax-2 device for ABO-major incompatible transplantation in adults

PURPOSE OF THE STUDY

In ABO-incompatible bone marrow transplantation, an efficient depletion of red blood cells (RBC) within the graft is mandatory to avoid adverse events in transplanted patients. Using non therapeutic products, we evaluated the substitution of the standard density gradient-based separation (DGBS) over Ficoll-Paque with the use of an automated procedure intended for buffy coat only (SmartRedux software) introducing modifications within the settings to achieve a drastic reduction of the initial volume of the product. Both methods were conducted on the Sepax-2 device.

SAMPLES AND METHODS

RBC depletion rates and CD34+ cells recoveries from eight procedures with SmartRedux software using "in-house" settings (method A) were compared to those obtained from four procedures using NeatCell software, an automated DGBS over Ficoll-Paque (method B).

RESULTS

Median erythrocyte depletion of 95,4% (92,7%-99,0%) and 99,8% (99,0%-99,9%) were observed using methods A and B, respectively. Median residual RBC volumes in the final product were 19 mL (4,4 mL-31,2 mL) and 0,7 mL (0,4 mL-4,7 mL), respectively (p = 0,014). CD34+ cells recoveries of 90,9% (62,7%-102,1%) and 78,4% (64,1%-86,2%) were achieved for methods A and B. Median platelet depletion was 16,6% (10%-42,7%) and 89,8% (88,5%-92,4%) using methods A and B, respectively (p = 0,004). Processing duration was shorter using method A (168 ± 29 min) than method B (295 ± 21 min) (p = 0,004).

CONCLUSION

Both methods achieved satisfactory erythrocyte depletion and CD34+ recovery. The use of Sepax-2 device in association with SmartRedux software could be extended to efficiently deplete RBC from large-volume BM in a raw instead of DGBS.

PROTOCOL OF NURSING CARE ON ZERO DAY OF THE TRANSPLANTATION OF HEMATOPOETIC STEM CELLS: COLLECTIVE CONSTRUCTION

ABSTRACT Objective: to construct a protocol of nursing care to the patient on day zero of hematopoietic stem cell transplantation. Method: a convergent care research was developed from August to December 2016 in a Bone Marrow Transplant Service. The participants were twenty-two nurses from this service. The technique of data collection used was discussion groups. For the analysis the following steps were taken: transcription of the data, highlighting the suggestions of the participants; distribution of contributions by theme, for synthesis of the elements in a coherent whole, scientific evidence and contributions of the participants; and construction of the protocol, with refinement and approval of the final version by nurses. Results: the protocol, guides nursing care to be provided by the nurse on day zero of hematopoietic stem cell transplantation, according to the infusion mode: fresh and cryopreserved-thawed. These precautions aim to prevent, identify and intervene early in complications related to cell infusion. Conclusion: the protocol, product of the research, was elaborated in the union of scientific evidences, with the reality of the service and the experience of the participating nurses. The utilization of the methodological steps of convergent care research was a facilitator, because, as it presupposes, it provided the union of care practice with scientific research. The participation of nurses in the construction and approval of the protocol enabled the subsequent implementation and use of this tool in nursing service.

Transfusion support for matched sibling allogeneic hematopoietic stem cell transplantation (1993-2010): factors that predict intensity and time to transfusion independence

BACKGROUND

Patients undergoing allogeneic hematopoietic stem cell transplant require variable, often extensive transfusion support. Identification of factors that predict urgent, intensive, or special needs should improve management of these patients.

STUDY DESIGN AND METHODS

This is a retrospective study of red blood cell (RBC) and platelet transfusion support provided for sequential matched sibling donor allogeneic transplants conducted at the Clinical Center, National Institutes of Health, from 1993 through 2010. Factors potentially important for predicting quantity of RBC and platelet transfusions, and time to transfusion independence through Day 200 following hematopoietic stem cell transplantation were evaluated.

RESULTS

Subjects (n = 800) received 10,591 RBC and 10,199 platelet transfusions. Multivariable analysis demonstrated that the need for RBC pretransplant, CD34+ dose, transplant year, diagnostic category, and ABO match were significantly independently associated with quantity of RBC transfusions during Days 0 through 30. Only pretransplant need for RBCs, CD34+ dose, and transplant year had significance during Days 0 through 100. Similar analyses for quantity of platelet transfusions demonstrated that for both Days 0 through 30 and 0 through 100 significant factors were need for platelet support before transplant, CD34+ dose, transplant year, and transplant regimen. Of note, long term, during Days 101 through 200, only CD34+ dose remained significant for quantity of RBC and platelet transfusions. Analysis of time to transfusion independence demonstrated that patients with ABO major mismatches required longer to achieve freedom from RBC transfusion support compared to identical matches or those with minor mismatches.

CONCLUSION

Patient-specific factors including CD34+ dose and ABO match of the graft should be given particular consideration by transfusion services when planning support of patients receiving allogeneic hematopoietic stem cell transplant.

Efficacy of three consecutive therapeutic plasma exchanges in major ABO-incompatible hematopoietic stem cell transplantation

INTRODUCTION

We retrospectively analyzed data of recipients who underwent three consecutive therapeutic plasma exchanges (TPEs) before major ABO-incompatible (ABOi) hematopoietic stem cell transplantation (HSCT) in our hospital from 2012 to 2017 and evaluated the efficacy of TPE for successful ABOi HSCT.

MATERIALS AND METHODS

We investigated the efficacy of TPE in 29 recipients with major ABOi HSCT based on the following: (1) requirement of red blood cell (RBC) transfusion during 100 days, (2) erythrocyte engraftment by reticulocyte count at 3 months, and (3) erythropoiesis recovery by bone marrow examination at 1 month and 3 months after ABOi HSCT.

RESULTS

IgM and IgG donor-specific isoagglutinins (DSIs) of 31 cases of TPE were significantly decreased after three consecutive TPEs (IgM median, 1:32 to 1:2, P < .0001; IgG median, 1:256 to 1:8, P < .0001). We divided a total of 31 TPEs into two groups depending on their final DSI titers after TPE (group F, DSI > 1:16; group S, DSI ≤ 1:16). RBC transfusions were required more by group F (median, 12 units) than those by group S (median, 2 units, P = .001). Relative frequencies of erythrocyte engraftment and normal erythropoiesis after ABOi HSCT showed higher tendencies in group S than those in group F.

DISCUSSION

Our study demonstrated that three consecutive TPEs were effective in reducing DSI titer in major ABOi HSCT. Reduction of pretransplant DSI in recipients could decrease requirement for RBC transfusion. Three consecutive TPEs are necessary for successful erythrocyte engraftment and normal erythropoiesis in this setting.

Incomplete Antibodies May Reduce ABO Cross-Match Incompatibility: A Pilot Study

OBJECTIVE

Any erythrocyte transfusion among humans having type A or B blood groups is impossible due to antibodies causing fatal transfusion complications. A cross-match test is performed to prevent immune transfusion complications before transfusion. Our hypothesis is that the fragment antibody (Fab) part of the antibody (incomplete antibody) may be used to prevent an immune stimulus related to the complete antibody. Therefore, we designed a pilot study to evaluate the effectiveness of these incomplete antibodies using cross-match tests.

MATERIALS AND METHODS

Pepsin enzyme and staphylococcal protein A columns were used to cut anti-A and anti-B monoclonal antibodies and purify their Fab (2) fragments, respectively. An Rh-positive erythrocyte suspension with purified anti-A Fab (2) solution and B Rh-positive erythrocyte suspension with purified anti-B Fab (2) solution were combined correspondingly. Cross-match tests were performed by tube and gel centrifugation methods. The agglutination levels due to the anti-A and anti-B Fab (2) antibodies and their effects on the agglutination normally observed with complete antibodies were then measured.

RESULTS

No agglutination for the purified incomplete anti-A Fab (2) with A Rh+ erythrocyte and anti-B Fab (2) with B Rh+ erythrocyte combinations was observed in the tube cross-match tests. These agglutination levels were 1+ in two wells in the gel centrifugation cross-match tests. Fab (2)-treated erythrocytes were also resistant to the agglutination that normally occurs with complete antibodies.

CONCLUSION

We determined that the Fab (2) fragments of antibodies may not only be used to obtain a mild or negative reaction when compared to complete antibodies, but they might also be used for decreasing ABO incompatibility. Incomplete antibodies might be a therapeutic option in autoimmune hemolytic anemia and they may also be used in solid organ or hematopoietic stem cell transplantation. Therefore, we have planned an in vivo study to prove these in vitro findings.

Passenger Lymphocyte Syndrome (PLS): A Single-center Retrospective Analysis of Minor ABO-incompatible Liver Transplants

Background and Aims: Due to the shortage of donor livers, minor ABO-incompatible liver transplantations are commonly performed. Together with the allograft, immunocompetent B-lymphocytes, called passenger lymphocytes, are transplanted. In case of minor ABO-incompatibility, these passenger lymphocytes produce antibodies directed towards the recipient's red blood cells, which causes immune-mediated hemolysis, also known as the passenger lymphocyte syndrome (PLS). Although this is a self-limiting disorder, serious complications can occur, including graft failure. Retrospectively, we evaluated the role of PLS in minor ABO-incompatible liver transplantations performed at our center. Methods: A retrospective analysis was conducted for all minor ABO-incompatible liver transplantations performed at the Antwerp University Hospital between 2003 and 2015. All patient files were inspected for clinical and laboratory findings. In cases of PLS diagnosis, the applied treatment was also studied. Results: In total, 10 patients underwent a minor ABO-incompatible liver transplantation and 4 showed signs of PLS. All 4 PLS patients were treated with different therapeutic strategy, corresponding to the severity of hemolysis. In all 4 cases, PLS resolved following treatment. Conclusion: When performing minor ABO-incompatible liver transplantations, knowledge of PLS is elemental. Next to a high index of clinical suspicion, we suggest routine screening for markers of hemolysis, with emphasis on haptoglobin level and direct antiglobulin test, weekly in the first 4 weeks post-transplantation as well as in case of a sudden hemoglobin drop within the first 3 months after transplantation. Peri- and postoperative transfusion support using donor-compatible blood has been suggested to prevent the occurrence or limit the extent of hemolysis.