Severe events in donors after allogeneic hematopoietic stem cell donation

Long-term follow-up of cancer and catastrophic diseases in hematopoietic stem cell donors: a comprehensive matched cohort study

Hematopoietic stem cell (HSC) transplantation, using either bone marrow (BM) or peripheral blood stem cells (PBSC), is a well-established therapy for various hematologic and non-hematologic diseases. However, the long-term health outcomes after HSC donation remain a major concern for several potential donors. Thus, we aimed to conduct a matched cohort study of 5003 unrelated donors (1099 BM and 3904 PBSC) and randomly selected 50,030 matched controls based on age, sex, and resident area from the donor registry between 1998 and 2018. The medical insurance claims of all the participants were retrieved from the Taiwan National Health and Welfare Data Science Center after de-identification. Our findings revealed no differences in the incidence of cancer, death, and catastrophic diseases between HSC donors and matched healthy participants during long-term follow-up. Kaplan-Meier curves depicting the cumulative incidence of cancer and overall mortality throughout the follow-up period also demonstrated similar outcomes between donors and non-donors. In conclusion, our results indicate that HSC donation, whether through BM or PBSC, is safe and not associated with an increased risk of cancer, death, or catastrophic diseases. These findings provide valuable information for counseling potential HSC donors and for long-term management of HSC donor health.

[Haematopoietic stem cell donation from minor donor: Respecting laws, assessing fitness, delivering information and good care (SFGM-TC)]

Haematopoietic stem cell collection from paediatric donors is a common and life-saving practice, as evidenced by the fact that there is a growing annual number of cases of transplants from minor donors among SFGM-TC centers over the last decade. Still, medical use of human tissue from a healthy and underage donor requires proper regulations and medical management. The guidelines below aim at underlining the importance of pondering the legal, medical and ethical aspects of using stem cells from healthy paediatric donors and stress out the importance of obtaining informed consent at the time of assessing HLA compatibility. Combined medical and psychological assessments are required before the donation, as well as one month later and one year later to ensure of the child's physical and mental wellbeing. Bone marrow harvest under general anaesthetics remains the preferred method of collection for children. Peripheral blood stem cell collection should only be considered for children who will not require a central venous access for collection. We aim at offering guidelines centered on the healthy child donating stem cells and his/her wellbeing, and these should be regularly reviewed as medical practices evolve.

A global assessment of hemostatic function of healthy allogeneic stem cell donors undergoing apheresis by rotational thromboelastometry

INTRODUCTION

Peripheral blood stem cell (PBSC) collection via apheresis requires the administration of granulocyte colony-stimulating factor (filgrastim) to stem cell donors. Several reports have shown that filgrastim administration and apheresis procedure induce a hypercoagulable state across PBSC collection, which might predispose certain donors to thrombotic complications.

METHODS

We evaluated the hemostatic functions of healthy allogeneic stem cell donors by rotational thromboelastometry (ROTEM). Blood samples from healthy donors (n = 30) were collected at defined time points: before filgrastim (baseline), on the day of apheresis before and after the procedure, and 1 week after apheresis.

RESULTS

The results indicated that hemostatic changes are temporary since all parameters in both EXTEM and INTEM assays are restored to their initial values 1 week after the apheresis.

CONCLUSION

We concluded that stem cell apheresis does not induce a hypercoagulable state in healthy donors. This is the first study evaluating the hemostatic functions of stem cell donors by ROTEM.

Incidence of cardiovascular disease in healthy Swedish peripheral blood stem cell donors - a nationwide study

Granulocyte colony-stimulating factor (G-CSF) is used in a majority of healthy donors to obtain peripheral blood stem cells for allogeneic stem cell transplantation. Since high levels of G-CSF activates endothelial cells and can induce a pro-coagulatory state, and fuelled by case reports of cardiovascular events in donors, some concerns have been raised about a potential for an increased risk of cardiovascular events for the donors after donation. We studied the incidence of cardiovascular disease following stem cell donation in a Swedish national register based cohort of 1098 peripheral blood stem cell donors between 1998 and 2016. The primary objective was to evaluate if the incidence of cardiovascular disease was increased for donors treated with G-CSF. The incidence of any new cardiovascular disease was 6.0 cases per 1000 person years, with a median follow up of 9.8 years. The incidence did not exceed that of age- sex- and residency-matched population controls (hazard ratio 0.90, 95% confidence interval (CI) 0.76-1.07, p-value 0.23), bone marrow donors, or non-donating siblings. Long-term cardiovascular disease incidence was not increased in this national register based study of peripheral blood stem cell donors treated with G-CSF.

Apheresis collection of mononuclear cells for chimeric-antigen receptor therapies

Collections of lymphocytes to be genetically modified to treat hematologic malignancies have seen a dramatic increase over the last few years as commercial products have been approved. Reports of new products in development that can possibly treat solid organ malignancies represent a massive change in the field. Apheresis is at the center of the collection of cells for the manufacture of these chimeric-antigen receptor therapy products. The expansion of these collections represents one of the areas of apheresis procedures growth. This review will summarize concepts important to this type of collection and variables that need to be optimized to obtain desired cell yields while increasing patients' safety.

Evaluating the efficiency and safety of large-volume leukapheresis using the Spectra Optia continuous mononuclear cell collection protocol for peripheral blood stem cell collection from healthy donors: A retrospective study

BACKGROUND

Large-volume leukapheresis (LVL) refers to processing of more than three volumes of blood in a single session for peripheral blood stem cell collection. Recently, continuous mononuclear cell collection (cMNC) protocol has been developed using the Spectra Optia system, which is a widely used apheresis device. LVL using the novel protocol has been investigated in patients. However, the efficiency and safety of LVL in healthy donors using this protocol has not been characterized. Therefore, this study aimed to evaluate the efficiency and tolerability of CD34+ collection of LVL with the cMNC protocol in healthy donors.

STUDY DESIGN AND METHODS

We retrospectively collected data on LVL (>3 total blood volume) and normal-volume leukapheresis (NVL) performed in healthy donors between October 2019 and December 2021. All procedures were performed using the cMNC protocol.

RESULTS

Although pre-apheresis CD34+ cell count was lesser in LVL (23.5 vs. 58.0/μL, p < .001), CD34+ collection efficiency was comparable between LVL and NVL (61.2% vs. 61.4%, p = .966). Platelet loss was significantly higher in LVL compared to NVL (38.0% vs. 29.4%, p < .001), with no correlation between attrition of platelet and processing blood volume. Moreover, the incidence of citrate toxicity during procedures was comparable between the two groups (31.6% vs. 21.4%, p = .322). All LVL procedures could be completed without any adverse events.

CONCLUSION

Allogeneic LVL procedure using Spectra Optia cMNC protocol was well tolerated by the donors and resulted in efficient collection of CD34+ cells, which was comparable to that of NVL.

Favorable recovery profiles and good reliability among youngest unrelated stem cell donors supports lowering the minimum donor registration age

INTRODUCTION

Younger donor age in hematopoietic cell transplantation has been associated with improved overall and disease-free survival. Safety data on peripheral blood stem cell (PBSC) and bone marrow (BM) donation is well established, including in the <18-year old age group in the related setting. In response, Anthony Nolan became the first stem cell donor registry to lower the minimum age for unrelated donors to 16-years.

MATERIALS AND METHODS

This retrospective study reviewed unrelated donors donating PBSC or BM for the first time between April 2015 and October 2017 since adoption of the lowered recruitment age. Data were collected from registry electronic database and structured follow-up questionnaires. Primary outcomes were turnaround time from VT to donation, optimal cell yield achievement, and physical and emotional recovery.

RESULTS

Out of a total of 1013 donors, there were no differences between the different age groups in proportion of donors achieving optimal CD34+ or TNC (PBSC and BM, respectively). There was no increased central line requirement for younger donors or increased emergency telephone support. Youngest donors were more likely to report physical recovery 2 and 7 days post-PBSC (P = .024 and P = .015, respectively) as well as an earlier emotional recovery (P = .001) and fewer physical symptoms 1 week BM donation (P = .04).

CONCLUSION

This study shows that younger donors are as reliable as older donors, and have favorable recovery profiles without need for increased support at any stage of the donation, supporting Anthony Nolan recruitment strategy and offering reassurance to donor registries considering the same.

Protection of haematopoietic progenitor cell donors: an updated overview of the European landscape

Haematopoietic progenitor cell donation from bone marrow and mobilised peripheral blood obtained from related and unrelated donors is an established procedure. The donation process in general has proven to be safe, but in rare cases severe and even fatal events have been reported. The present study aimed at providing a description of the current situation of donor protection measures in Council of Europe member States. A specific questionnaire was developed to compile information on donation activities, graft sources, legal frameworks, donor protection measures, collection of donor outcome data, and long-term follow-up of paediatric and adult related and unrelated donors. The outcome of this survey served as a basis for elaborating the Recommendation CM/Rec(2020)6 of the Committee of Ministers to member States on establishing harmonised measures for the protection of haematopoietic progenitor cell donors.

Severe short-term adverse events in related bone marrow or peripheral blood stem cell donors

The incidence of severe adverse events (SAEs) and associated risk factors in hematopoietic cell transplantation donors needs to be clarified for related donors (relatives of the transplant recipient), whose criteria for donation are more lenient than for unrelated donors. Data from related donors registered in the Japanese national data registry database between 2005 and 2021 were evaluated to determine the association of short-term SAE incidence with donor characteristics at registration.Fourteen of 4339 bone marrow (BM) donors (0.32%) and 54 of 10,684 peripheral blood stem cell (PBSC) donors (0.51%) experienced confirmed SAEs during the short donation period. No deaths were observed. Past medical history was a common risk factor for SAEs in both BM and PBSC donors. Age of 60 years or older and female sex were identified as risk factors for SAEs in PBSC donors. Female sex was also a risk factor for poor mobilization, which resulted in discontinuation of PBSC collection.Although donors should be selected carefully, a certain level of safety is ensured for related donors in Japan. Donor safety should be further increased by improving the selection method for related donors and extending the follow-up period.

Worries and Psychological Well-Being in Potential Hematopoietic Stem Cell Donors Before Donation-A Swedish National Study

BACKGROUND

The physical risks involved in donating hematopoietic stem cells have been thoroughly studied, but little is known about the psychological risks potential donors might face before donation. The aim of this study was to describe potential the pre-donation worries and psychological well-being of hematopoietic stem cell donors and investigate possible associations between donor characteristics and psychological well-being.

METHODS

In a cross-sectional, national cohort study, we describe pre-donation worries and psychological well-being and investigate possible associations between donor characteristics and psychological well-being. A questionnaire was sent to prospective adult hematopoietic stem cells donors.

RESULTS

The study included 210 participants, 47% of whom were related and 53% unrelated to the recipient. Of the participants, 39% reported great worry about the recipient and 12% great worry about themselves as potential donors. Symptoms of anxiety were expressed by 21%, whereas symptoms of depression were uncommon and perceived general mental health was slightly lower than in the Swedish population. Great worry about oneself, lower age, and female sex were related to increased anxiety and lower mental health.

CONCLUSION

This study highlighted that some potential donors report high levels of pre-donation worry and that greater worry about oneself, lower age, and female sex are associated with lower psychological well-being. Although further studies are needed to investigate this psychological risk over time, it is clear that some potential donors are particularly vulnerable.

Adverse events related to central venous catheters (CVC) and the influence of CVC characteristics on peripheral blood hematopoietic progenitor cell collection in children

Introduction

The use of peripheral blood progenitor cells (PBPCs) as a source for hematopoietic stem cell transplantation (HSCT) in pediatric healthy donors is still under debate. The risk of a central venous catheter (CVC) placement and catheter-related complications continue to be the main arguments to discourage its use.

Methods

we present a retrospective analysis of 140 PBPC collections in pediatric patients and donors, describing adverse events (AE) related to CVCs as well as the influence of catheterrelated variables on the efficiency of the leukapheresis.

Results

14 CVC-related AEs were recorded (10%). The most common was fever in 5 patients, 4 of which had a catheter-related bacteriemia. Thrombotic events were only observed in 3 patients with active malignancy. A healthy donor presented a moderate bleeding after catheter withdrawal that resolved with local measures, and none of the rest presented any AE. Regarding variables related to the development of AEs, the subject group (patient or donor) was the only one significantly associated (p < 0.0001). Of interest, efficiency was also related to catheter location, being worse in those located in the femoral vein than in into the jugular or the subclavian veins (p < 0.05). In a multivariate analysis, the only variable significantly associated was catheter size (beta 0.238, p < 0.01).

Discussion

Placing a CVC for PBPC collection in pediatric subjects is overall safe; CVC-related complications in pediatric healthy donors are very rare. Furthermore, we should try to place catheters of the largest caliber possible, since the efficiency of the collection is related to this variable.

Suitability of haematopoietic cell donors: updated consensus recommendations from the WBMT standing committee on donor issues

The contribution of related donors to the globally rising number of allogeneic haematopoietic stem cell transplantations (HSCT) remains increasingly important, particularly because of the growing use of haploidentical HSCT. Compared with the strict recommendations on the suitability for unrelated donors, criteria for related donors allow for more discretion and vary between centres. In 2015, the donor outcome committee of the Worldwide Network for Blood and Marrow Transplantation (WBMT) proposed consensus recommendations of suitability criteria for paediatric and adult related donors. This Review provides updates and additions to these recommendations from a panel of experts with global representation, including the WBMT, the European Society for Blood and Marrow Transplantation donor outcome committee, the Center for International Blood and Marrow Transplant Research donor health and safety committee, the US National Marrow Donor Program, and the World Marrow Donor Association, after review of the current literature and guidelines. Sections on the suitability of related donors who would not qualify as unrelated donors have been updated. Sections on communicable diseases, clonal haematopoiesis of indeterminate potential, paediatric aspects including psychological issues, and reporting on serious adverse events have been added. The intention of this Review is to support decision making, with the goal of minimising the medical risk to the donor and protecting the recipient from transmissible diseases.

Basic characteristics and safety of donation in related and unrelated haematopoietic progenitor cell donors - first 10 years of prospective donor follow-up of Swiss donors

Since July 2007 prospective life-long follow-up (FU) for unrelated (URD) and related donors (RD) is mandatory in Switzerland and data on every allogeneic haematopoietic progenitor cell (HPC) donation are collected prospectively. We report the real-world experience of HPC donation during a 10-year study period (01.07.2007-30.06.2017) with basic characteristics and FU data. 1105 donors underwent 1155 HPC donation procedures. Eighty percent of first donations performed by 802 (73%) RDs and 303 (27%) URDs were peripheral blood stem cells (PBSC), 20% bone marrow (BM). Male donors were over-represented as URD (60% male vs 40% female). Main differences between RDs and URDs concerned age and pre-existing health disorders. RDs were significantly older at first donation (median age 48 years) compared to URD (34 years, p < 0.0001) and had more pre-existing health problems: 25% vs 9% in URD (p < 0.0001). No fatal complications occurred, collection related severe adverse events (SAE) after first donation were not significantly different between groups (RD 1.2%, URD 0.99%), incidence rates for neoplastic and autoimmune diseases did not exceed the rates of the general population. RDs are a more heterogeneous and potentially more vulnerable group, but if donor evaluation is performed appropriately, HPC donation is still safe.

Cancer incidence in healthy Swedish peripheral blood stem cell donors

Granulocyte colony-stimulating factor (G-CSF) has been used for over 20 years to obtain peripheral blood stem cells from healthy donors for allogeneic stem cell transplantation. Concerns have been raised about a potentially increased cancer incidence in donors after donation, especially regarding haematological malignancies. In a prospective Swedish national cohort study, we studied the cancer incidence after donation in 1082 Swedish peripheral blood stem cell donors, donating between 1998 and 2014. The primary objective was to evaluate if the cancer incidence increased for donors treated with G-CSF. With a median follow-up time of 9.8 years, the incidence of haematological malignancies was 0.85 cases per 1000 person-years, and did not significantly differ from the incidence in age-, sex- and residence-matched population controls (hazard ratio 1.70, 95% confidence interval (CI) 0.79-3.64, p value 0.17), bone marrow donors or non-donating siblings. The total cancer incidence for peripheral blood stem cell donors was 6.0 cases per 1000 person-years, equal to the incidence in matched population controls (hazard ratio 1.03, 95% CI 0.78-1.36, p value 0.85), bone marrow donors or non-donating siblings. In this study of healthy peripheral blood stem cell donors, the cancer incidence was not increased after treatment with G-CSF.

Hematopoietic Progenitor Cell Donation from Healthy Female Donors During Pregnancy: A Report of 10 Cases

The golden rule when collecting hematopoietic progenitors (HPs) from healthy volunteers is "donor safety." Pregnancy is an absolute contraindication for HP collection from unrelated donors; however, collection from a related pregnant donor is sometimes considered based on the urgency of the indication for transplantation and the available alternatives. Data on the safety and efficacy of this practice are limited. We conducted a retrospective chart review of an institution's transplantation database to characterize the safety and efficacy of HP donation from pregnant donors. Ten cases of HP donation from pregnant donors were identified, including 6 bone marrow grafts and 4 peripheral blood stem cell grafts. The median age of donors was 27.5 years. The median volume of the collected product was 521 mL (range, 128 to 1160 mL), the median number of total nucleated cells (TNCs) in the graft was 252 × 10⁸ (range, 30.5 to 794 × 10⁸), the median TNC concentration in the graft was 37 × 10⁶ per mL (range, 4.7 to 214.6 × 10⁶ per mL). The median number of CD34 cells in the graft was 142 × 10⁶ (range, 6 to 763 × 10⁶), and the median CD34 concentration in the graft was 20 × 10⁴ per mL (range, 2 to 206 × 10⁴ per mL). There were no safety issues or signals related to the procedure. HP collection from pregnant donors is relatively safe. This case series provides valuable information for practicing transplant physicians on how to counsel pregnant donors when this scenario is encountered in clinical practice.

Acute glomerulonephritis in a hematopoietic blood stem cell donor

Use of granulocyte colony-stimulating factor (G-CSF) has been associated with side effects including reports of acute glomerulonephritis (GN), almost all of which have been immune complex associated. There is one prior report of pauci-immune GN in a child, but was negative for ANCA (anti-neutrophilic cytoplasmic antibodies). We describe the first case of ANCA-positive pauci-immune GN exacerbated by the use of G-CSF for peripheral blood stem cell (PBSC) donation in a patient with no prior history of vasculitis. Given the use of G-CSF in PBSC donation and neutropenias associated with various conditions, it is important that both the nephrologist and the hematologist are aware of the renal risks associated with its use.

Moral Distress: Its Manifestations in Healthy Donors during Peripheral Blood Hematopoietic Stem Cell Harvesting

Hematopoietic stem cell donors (HSCDs) may have ambivalent feelings about donation. These feelings are related to moral obligation to help a sick relative and/or fear about the donation procedure. This ambivalence can produce moral distress (MD) and anxiety, which are usually unnoticed by the treating physician. The aim of this study was to evaluate the incidence of MD and anxiety in a group of related HSCDs for allogeneic transplantation. In this prospective observational study, to assess MD and anxiety, we applied 3 self-answered questionnaires-a questionnaire developed to assess MD (MDQ), State Trait Anxiety Index (STAI), and Edmonton Symptom Assessment System (ESAS)-before, during, and after hematopoietic stem cell donation. A total of 60 consecutive related HSCDs with a mean age of 38.2 years were included. Thirty-six were male. Hematopoietic stem cell collections were done by apheresis, performed as an outpatient process in all cases. The incidence of MD during the donation process was 56%. The proportion of HSCDs with moderate to high state anxiety decreased significantly from before donation (63%) to after donation (30%). Higher scores for MD correlated with higher scores on the STAI questionnaire (r = 0.448; P < .005). Thirty-seven donors (62%) had at least 1 physical symptom even before the stem cell mobilization process started, mainly anxiety (33%), difficulty sleeping (33%), and fatigue (30%). The number of symptomatic donors increased during donation (100%) and decreased after the procedure (80%). We conclude that MD and anxiety symptoms experienced by HSCDs are very common and can be explained by mixed feelings about the donation process. Providing comprehensive psychological support before starting the donation process and guaranteeing respect for the donor's autonomy are needed to decrease the negative impact of the donation experience.

Comparison of the efficacy of hematopoietic stem cell mobilization regimens: a systematic review and network meta-analysis of preclinical studies

BACKGROUND

Mobilization failure may occur when the conventional hematopoietic stem cells (HSCs) mobilization agent granulocyte colony-stimulating factor (G-CSF) is used alone, new regimens were developed to improve mobilization efficacy. Multiple studies have been performed to investigate the efficacy of these regimens via animal models, but the results are inconsistent. We aim to compare the efficacy of different HSC mobilization regimens and identify new promising regimens with a network meta-analysis of preclinical studies.

METHODS

We searched Medline and Embase databases for the eligible animal studies that compared the efficacy of different HSC mobilization regimens. Primary outcome is the number of total colony-forming cells (CFCs) in per milliliter of peripheral blood (/ml PB), and the secondary outcome is the number of Lin^- Sca1⁺ Kit⁺ (LSK) cells/ml PB. Bayesian network meta-analyses were performed following the guidelines of the National Institute for Health and Care Excellence Decision Support Unit (NICE DSU) with WinBUGS version 1.4.3. G-CSF-based regimens were classified into the SD (standard dose, 200-250 μg/kg/day) group and the LD (low dose, 100-150 μg/kg/day) group based on doses, and were classified into the short-term (2-3 days) group and the long-term (4-5 days) group based on administration duration. Long-term SD G-CSF was chosen as the reference treatment. Results are presented as the mean differences (MD) with the associated 95% credibility interval (95% CrI) for each regimen.

RESULTS

We included 95 eligible studies and reviewed the efficacy of 94 mobilization agents. Then 21 studies using the poor mobilizer mice model (C57BL/6 mice) to investigate the efficacy of different mobilization regimens were included for network meta-analysis. Network meta-analyses indicated that compared with long-term SD G-CSF alone, 14 regimens including long-term SD G-CSF + Me6, long-term SD G-CSF + AMD3100 + EP80031, long-term SD G-CSF + AMD3100 + FG-4497, long-term SD G-CSF + ML141, long-term SD G-CSF + desipramine, AMD3100 + meloxicam, long-term SD G-CSF + reboxetine, AMD3100 + VPC01091, long-term SD G-CSF + FG-4497, Me6, long-term SD G-CSF + EP80031, POL5551, long-term SD G-CSF + AMD3100, AMD1300 + EP80031 and long-term LD G-CSF + meloxicam significantly increased the collections of total CFCs. G-CSF + Me6 ranked first among these regimens in consideration of the number of harvested CFCs/ml PB (MD 2168.0, 95% CrI 2062.0-2272.0). In addition, 7 regimens including long-term SD G-CSF + AMD3100, AMD3100 + EP80031, long-term SD G-CSF + EP80031, short-term SD G-CSF + AMD3100 + IL-33, long-term SD G-CSF + ML141, short-term LD G-CSF + ARL67156, and long-term LD G-CSF + meloxicam significantly increased the collections of LSK cells compared with G-CSF alone. Long-term SD G-CSF + AMD3100 ranked first among these regimens in consideration of the number of harvested LSK cells/ml PB (MD 2577.0, 95% CrI 2422.0-2733.0).

CONCLUSIONS

Considering the number of CFC and LSK cells in PB as outcomes, G-CSF plus AMD3100, Me6, EP80031, ML141, FG-4497, IL-33, ARL67156, meloxicam, desipramine, and reboxetine are all promising mobilizing regimens for future investigation.

Prevention of hypokalaemia and hypomagnesaemia following peripheral stem cell collection - a prospective cohort study

BACKGROUND AND OBJECTIVES

Citrate-based anticoagulation reduces plasma potassium and free magnesium in patients undergoing peripheral stem cell collections. Whether the effects may be mitigated by pre-procedure oral electrolyte supplements has not been previously assessed.

MATERIALS AND METHODS

Results from a historic cohort (2010-2013) guided a systematic prospective intervention in subjects deemed at risk for clinically meaningful hypokalaemia and hypomagnesaemia. From 2015 to 2019, 136 patients were enrolled in the study. Pre- and post-apheresis electrolyte levels were measured, and oral potassium and magnesium supplements were systematically administered based on the pre- electrolyte levels.

RESULTS

We saw a 37% absolute reduction in severe hypokalaemia and 39% absolute reduction in hypomagnesaemia in the prospective intervention cohort when compared to the historic cohort. Multivariate analyses indicated that part of the effect was due to the electrolyte intervention, while part of the effect likely stemmed from other procedure-related changes implemented during the study period.

CONCLUSION

Oral potassium and magnesium prophylaxis appear to reduce hypokalaemia and hypomagnesaemia following peripheral stem cell collection. Whether the effect size is sufficient to motivate the intervention warrants further investigation, preferably in a prospective randomized trial setting.

Young haploidentical donor versus fully matched elderly donor: An observational study on patients aged 50 years or older underwent hematopoietic progenitor cells transplantation

INTRODUCTION

Stem cell transplantation has been a therapeutic option for increasingly older patients but the search for the donor is an additional question in this context. Currently the ideal donor is a sibiling with fully compatible human leukocyte antigens, but when it is an elderly patient there is a high probability that this donor is also elderly, and the donor age has been related to worse outcomes and the possible comorbidities may render the donor ineligible.

OBJECTIVE

To compare, in patients aged 50 years or older, the overall survival of patients whose donor had haploidentical HLA compatibility and under 50 years of age ("young" donor) versus patients whose donor had a total HLA compatibility and 50 years of age or older ("elderly" donor).

METHODS

This is a consecutive retrospective descriptive observational epidemiological study. All patients were treated during the period from January, 2010 to April, 2019. Overall survival of patients 50 years of age and older was the primary outcome of the study.

RESULT

We included 53 patients. In the multivariate analysis we found no statistically significant difference in overall survival between patients whose donor had fully HLA compatible aged 50 years and older and patients whose donor had haploidentical HLA compatible and aged up to 50 years (p = 0.135).

CONCLUSION

The results obtained in the study show that for patients aged 50 years or older, a donor with haploidentical human leukocyte antigen compatibility and age below 50 years can be chosen without impairing overall survival.

« Faire le deuil » en temps d’innovations thérapeutiques

Nous traitons la problématique du deuil dans le cadre de l’allogreffe de cellules souches hématopoïétiques à partir d’un donneur haplo-identique. L’analyse d’un cas clinique permet d’interroger l’application systématique des catégories du normal et du pathologique au deuil, la surmédicalisation des sujets endeuillés ainsi que l’injonction sociale à « faire son deuil », selon les modalités décrites par la nosographie psychiatrique. Les modalités d’accompagnement des donneurs endeuillés seront questionnées en réaffirmant la pertinence d’une clinique nourrie par une réflexion psychanalytique.

Ziyuglycoside II alleviates cyclophosphamide-induced leukopenia in mice via regulation of HSPC proliferation and differentiation

Ziyuglycoside II (ZGS II) is a major bioactive ingredient of Sanguisorbae officinalis L., which has been widely used for managing myelosuppression or leukopenia induced by chemotherapy or radiotherapy. In the current study, we investigated the pro-hematopoietic effects and underlying mechanisms of ZGS II in cyclophosphamide-induced leukopenia in mice. The results showed that ZGS II significantly increased the number of total white blood cells and neutrophils in the peripheral blood. Flow cytometry analysis also showed a significant increase in the number of nucleated cells and hematopoietic stem and progenitor cells (HSPCs) including ST-HSCs, MPPs, and GMPs, and enhanced HSPC proliferation in ZGS II treated mice. The RNA-sequencing analysis demonstrated that ZGS II effectively regulated cell differentiation, immune system processes, and hematopoietic system-related pathways related to extracellular matrix (ECM)-receptor interaction, focal adhesion, hematopoietic cell lineage, cytokine-cytokine receptor interaction, the NOD-like receptor signaling pathway, and the osteoclast differentiation pathway. Moreover, ZGS II treatment altered the differentially expressed genes (DEGs) with known functions in HSPC differentiation and mobilization (Cxcl12, Col1a2, and Sparc) and the surface markers of neutrophilic precursors or neutrophils (Ngp and CD177). Collectively, these data suggest that ZGS II protected against chemotherapy-induced leukopenia by regulating HSPC proliferation and differentiation.

Health-related quality of life in peripheral blood stem cell donors and bone marrow donors: a prospective study in Japan

Understanding of the impact of stem cell donation on donors' health-related quality of life (HRQOL) remains limited. A prospective observational study of eligible unrelated donors enrolled in the Japan Marrow Donor Program was conducted to compare HRQOL and adverse events (AEs) between peripheral blood stem cell (PBSC) and bone marrow (BM) donors. In total, 107 PBSC donors and 108 BM donors were enrolled. HRQOL scores for physical status were significantly lower in BM donors 1 week post-harvest (P < 0.001), but there were no significant differences between the two groups at baseline or 3 months post-harvest. PBSC donors were more likely to experience AEs before harvest (P < 0.001). However, at harvest, moderate-to-severe AEs were more common in BM donors (P = 0.001). After harvest, all grades of AEs were significantly higher in BM donors (P < 0.001). Among BM donors, a lower total physical score at baseline [odds ratio (OR) 1.21], female sex [OR 2.71], and young donors (OR 3.08) were risk factors for moderate-to-severe AEs at harvest, while among PBSC donors, only female sex (OR 4.86) was a risk factor. Our findings show better HRQOL during PBSC donation. These data help support decision-making by potential donors.

Collection of Peripheral Blood Progenitor Cells in 1 Day Is Associated with Decreased Donor Toxicity Compared to 2 Days in Unrelated Donors

Peripheral blood stem cells (PBSCs) have been increasingly used for allogeneic hematopoietic cell transplantation instead of bone marrow stem cells. Current National Marrow Donor Program policy recommends 5 days of daily filgrastim, followed by either 1 or 2 days of apheresis for unrelated donors, depending on collection center choice. To date, there are no published studies comparing the differences in donor experience between 1 day and 2 days of apheresis. We examined 22,348 adult unrelated donor collections in 184 centers between 2006 and 2016. Of these 22,348 donors, 20,004 (89.5%) had collection on 1 day, and the other 2344 (9.5%) had collection over 2 days. Information on why donors underwent apheresis in 1 day or 2 days was not available. Donors who underwent apheresis in 1 day were more likely to be male (67% versus 46%; P < .001), younger (age <30 years, 48% versus 36%; P < .001), and have a higher body weight (83.0 kg versus 75.9 kg; P< .001) and body mass index (BMI; >30, 30% versus 22%; P < .001). Successful collection of the requested CD34⁺ cell count was achieved on the first day in 82% of 1-day collections and in 16% of 2-day collections. Despite not administering filgrastim the evening after the first day of collection in patients who underwent 2 days of apheresis, the median concentration of CD34⁺ cells/L in the product was higher on the second day of apheresis compared with the first day (23.8 × 10⁶ CD34⁺/L on day 1 versus 28.7 × 10⁶ CD34⁺/L on day 2; P< .001). Donors who underwent collection in 1 day were less likely to experience citrate toxicity (36% versus 52%; P< .001), hospitalization (1% versus 6%; P< .001), and other side effects related to apheresis (Modified Toxicity Criteria incidence: 20% versus 26%; P < .001). Female sex, older age, collection via central lines, and higher BMI were factors associated with greater likelihood for the development of toxicity, whereas less toxicity was noted in those with higher CD34⁺ counts and more blood processed on the first day of collection. We conclude that although unrelated donors can be successfully collected in 1 day or 2 days, 1-day apheresis procedures were associated with less overall toxicity, and thus we recommend single-day collections, especially if the requested number of cells have been collected in 1 day.

Donor Evaluation for Hematopoietic Stem and Progenitor Cell Collection

With the increasing incidence of hematopoietic allogeneic cell transplantation (allo-HCT), the importance of securing a cellular product, safely from a donor, and ensuring that the product is without additional risk to the recipient, continues to be of paramount importance. The evaluation of the donor’s medical eligibility and suitability is designed to identify and limit the risk of transmitting infectious, genetic, or neoplastic diseases to the recipient through the product. It also aims to ensure a maximum level of safety for the donor and informs them of the risks of donation. Several regulatory agencies, national and international registries, and accreditation bodies have facilitated the availability and safe provision of human cells, tissues, and cellular- and tissue-based products not only at local institutions but also through international exchange.

Expansion of Haematopoietic Stem and Progenitor Cells: Paving the Way for Next-Generation Haematopoietic Stem Cell Transplantation

Haematopoietic stem cell transplantation (HSCT) is now an established practice with over 70,000 transplants performed annually, and over 1.5 million around the world so far. The practice of HSCT has improved over the years due to advances in conditioning regiments, preparatory practices for patients leading up to the transplant, graft versus host disease (GVHD) and infection prophylaxis, as well as a better selection of patients. However, in many instances, the stem cells supplied to the patient may not be adequate for optimal transplantation outcomes. This may be seen in a few areas including umbilical cord blood transplantation, inadequate bone marrow, peripheral blood stem cell harvest, or gene therapy. Growing and expanding HSCs in culture would provide an increase in cell numbers prior to stem cell infusion and accelerate haematopoietic recovery, resulting in improved outcomes. Several new technologies have emerged in recent years, which have facilitated the expansion of haematopoietic stem and progenitor cells (HSPCs) in culture with good outcomes in vitro, in vivo, and in clinical trials. In this review, we will outline some of the reasons for the expansion of HSPCs as well as the new technologies facilitating the advances in HSCT.

Mobilization and collection of cells in the hematologic compartment for cellular therapies: Stem cell collection with G-CSF/plerixafor, collecting lymphocytes/monocytes

An essential and influential first step in all cellular therapies is collecting donor or patient cells. In hematopoietic progenitor cell transplantation, autologous or allogeneic hematopoietic progenitor cells (HPCs) are collected from either the bone marrow or the peripheral blood. Peripheral blood collection by apheresis requires mobilization with chemotherapy, granulocyte colony stimulating factor (G-CSF), plerixafor, or a combination. The modalities of mobilization and collection each carry a unique set of risks and benefits for both the donor and the recipient. In other types of cell therapy, most notably chimeric antigen receptor T cells, lymphocytes or monocytes are collected from the peripheral blood. The risks of collecting these cells by apheresis are similar to HPCs, but less is known about the composition, timing and qualitative cell characteristics which contribute to an optimal collection. Here, we review the mobilization and collection of HPCs and the collection of lymphocytes and monocytes. Donor safety is of primary importance when collecting material for any type of cell therapy. Every aspect of mobilization and collection can be studied and potentially optimized to improve patient outcomes.

Hematopoietic cell transplant nurse coordinators' perceptions of related donor care: a European survey from the EBMT Nurses Group

Allogeneic haematopoietic cell transplantation (HCT) is a curative procedure for patients with haematological malignancies and immune deficiencies. A human leukocyte antigen (HLA) identical sibling is only available for 25-35% of patients in need. The improvement in haplo-identical transplantation has led to a marked increase in cell donation from relatives. Despite international recommendations, discrepancies in related-donors (RD) care exist between centres, particularly regarding medical suitability criteria, consenting procedures and donor follow-up. This European survey aimed to explore hematopoietic cell transplantation coordinators nurses' (HCT-CNs) perceptions of RD care, in particular the association with the presence or not of an independent unit (IU). Ninety-three HCT-CNs from seventy-six EBMT centres responded, representing 19 countries (response rate: 27%). Our results did not show a significant association between IU and HCT-CNs perceptions of related-donors care. The practices for RD care vary among centres regarding presence or not of an IU (48%), person caring for RD (haematologist in 54%, HCT physician in 17%, HCT-CNs in 20%), person to whom the results of HLA typing are communicated, use of a booklet for RD, follow-up or not and periodicity of follow-up. Qualitative data highlight the related-donation ethical issues and the need for improvement in RD care. HCT-CNs' main concerns were: the necessary confidentiality to insure the voluntary status of RD, the perceived conflict of interest felt by professionals when managing both patients and RD, plus the psychosocial aspects of related-donation. Even if there is a variety of a practice among centres, the presence of an IU is not significantly associated with an improvement in RD care.

Feasibility and cost analysis of day 4 granulocyte colony-stimulating factor mobilized peripheral blood progenitor cell collection from HLA-matched sibling donors

BACKGROUND

Guidelines recommend treatment with 4-5 days of granulocyte colony-stimulating factor (G-CSF) for optimal donor peripheral blood progenitor cell (PBPC) mobilization followed by day 5 collection. Given that some autologous transplant recipients achieve adequate collection by day 4 and the possibility that some allogeneic donors may maximally mobilize PBPC before day 5, a feasibility study was performed evaluating day 4 allogeneic PBPC collection.

METHODS

HLA-matched sibling donors underwent collection on day 4 of G-CSF for peripheral blood (PB) CD34⁺ counts ≥0.04 × 10⁶/mL, otherwise they underwent collection on day 5. Those with inadequate collected CD34⁺ cells/kg recipient weight underwent repeat collection over 2 days. Transplant and PBPC characteristics and cost analysis were compared with a historical cohort collected on day 5 per our prior institutional algorithm.

RESULTS

Of the 101 patient/donor pairs, 50 (49.5%) had adequate PBPC collection on day 4, with a median PB CD34⁺ cell count of 0.06 × 10⁶/mL. Day 4 donors were more likely to develop bone pain and require analgesics. Median collected CD34⁺ count was significantly greater, whereas total nucleated, mononuclear and CD3⁺ cell counts were significantly lower, at time of transplant infusion for day 4 versus other collection cohorts. There were no significant differences in engraftment or graft-versus-host disease. Cost analysis revealed 6.7% direct cost savings for day 4 versus historical day 5 collection.

DISCUSSION

Day 4 PB CD34⁺ threshold of ≥0.04 × 10⁶/mL identified donors with high likelihood of adequate PBPC collection. Day 4 may be the optimal day of collection for healthy donors, without adverse effect on recipient transplant outcomes and with expected cost savings.

[Related donors follow-up: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

Since 2010 there has been an exponential increase of the number of transplants performed from related donors. The development of haploidentical transplants increases the resort to related-donation, which presents two main advantages: a less important financial cost and a faster availability of the graft. Standards for mandatory accreditation exist, but the adherence to these recommendations is not optimal: currently, different practices regarding the organizational modalities of care, recruitment criteria, qualification and follow-up of related donors have been observed among French transplant centers. The Francophone Society of Marrow Transplant and Cellular Therapy (SFGM-TC) has developed guidelines for the consent and the non-eligibility criteria for hematopoietic stem cell donors. A multidisciplinary group has devised a booklet as a medium to inform donors about hematopoietic cell donation and transplantation in a clear and accessible language. This paper provides recommendations on post-donation follow-up, taking into account both medical standards and organizational constraints of French centers. Some tools are proposed.

Lower platelet count with increased density of platelet antigens in granulocyte colony-stimulating factor mobilized peripheral blood stem cell donors

BACKGROUND/PURPOSE

Granulocyte colony-stimulating factor (G-CSF) is widely used for prophylaxis and treatment of neutropenia in cancer patients and also for peripheral blood stem cells (PBSC) mobilization. The aim of this study is to evaluate the possible changes of platelet surface antigens after G-CSF injection in PBSC donors compared with healthy control.

METHODS

Between January 1st and December 31st, 2014, 48 healthy voluntary PBSC donors were eligible for this study. Donors received G-CSF (Filgrastim) subcutaneously for five days, and then their whole blood was collected for complete blood count. Analysis of platelet antigens was performed by flow cytometry. Sixteen healthy controls were also included for comparison.

RESULTS

Lower platelet counts were found in PBSC donors after G-CSF use and in comparison with health controls. The platelet size evaluated by forward scattering (FSC) showed smaller platelets in PBSC donors after G-CSF use compared with healthy controls (39.3 vs 46.7 mean fluorescence intensity, P = 0.015). CD31 were higher in PBSC donor (203.2 vs. 120.7, P < 0.001). Except CD31, other platelet surface antigens were not different between PBSC donors and healthy controls. After adjusting by FSC data, the mean antigen intensity/FSC of CD31, CD41a, CD42a, CD42b and CD61 showed 5.45 vs 2.78 (P < 0.001), 4.35 vs 3.47 (P = 0.007), 3.87 vs 3.17 (P = 0.015), 20.45 vs 16.94 (P = 0.045), and 5.98 vs 4.88 (P = 0.018) respectively.

CONCLUSION

We noted higher density of platelet surface antigens, lower platelet count and smaller platelet size after G-CSF injection.

Challenge to Predict Mobilized Peripheral Blood Stem Cells on the Fourth Day of Granulocyte Colony-Stimulating Factor Treatment in Healthy Donors: Predictive Value of Basal CD34+ Cell and Platelet Counts

A longitudinal, prospective, observational, single-center cohort study on healthy donors was designed to identify predictors of CD34⁺ cell mobilization on day 4 after granulocyte colony-stimulating factor (G-CSF) administration. As potential predictors of mobilization, age, sex, body weight, height, blood volume, WBC count, peripheral blood (PB) mononuclear cell count, platelet (Plt) count, and hematocrit and hemoglobin levels were considered. Two different evaluations of CD34⁺ cell counts were determined for each donor: baseline (before G-CSF administration) and in PB on day 4 after G-CSF administration. One hundred twenty-two consecutive healthy donors with a median age of 47.5 years were enrolled. The median value of CD34⁺ on day 4 was 43 cells/µL (interquartile range, 23 to 68), and 81.1% of donors had ≥20 cells/µL. Basal WBC count, Plt count, and CD34⁺ were significantly higher for the subjects with CD34⁺ levels over median values on day 4. A multivariate quartile regression analysis, adjusted by sex, age, basal CD34⁺, and basal Plt count, showed a progressively stronger relationship between baseline CD34⁺ and Plt levels and the CD34⁺ levels on day 4. The basal CD34⁺ cut-off level to predict the levels of CD34⁺ on day 4 was either ≤2 cells/μL or ≥3 cells/μL and that of basal Plt count was ≤229 × 10⁹/L or ≥230 × 10⁹/L, respectively, to determine whether mobilization therapy should or should not be attempted. PB stem cell mobilization with G-CSF was highly effective on day 4, and herein we describe a model for predicting the probability of performing PB stem cell collection after a short course of G-CSF.

The Meaning of Being a Living Kidney, Liver, or Stem Cell Donor-A Meta-Ethnography

BACKGROUND

Studies on living donors from the donors' perspective show that the donation process involves both positive and negative feelings involving vulnerability. Qualitative studies of living kidney, liver, and allogeneic hematopoietic stem cell donors have not previously been merged in the same analysis. Therefore, our aim was to synthesize current knowledge of these donors' experiences to deepen understanding of the meaning of being a living donor for the purpose of saving or extending someone's life.

METHODS

The meta-ethnography steps presented by Noblit and Hare in 1988 were used.

RESULTS

Forty-one qualitative studies from 1968 to 2016 that fulfilled the inclusion criteria were analyzed. The studies comprised experiences of over 670 donors. The time since donation varied from 2 days to 29 years. A majority of the studies, 25 of 41, were on living kidney donors. The synthesis revealed that the essential meaning of being a donor is doing what one feels one has to do, involving 6 themes; A sense of responsibility, loneliness and abandonment, suffering, pride and gratitude, a sense of togetherness, and a life changing event.

CONCLUSIONS

The main issue is that one donates irrespective of what one donates. The relationship to the recipient determines the motives for donation. The deeper insight into the donors' experiences provides implications for their psychological care.

Reproductive Outcomes After a Childhood and Adolescent Young Adult Cancer Diagnosis in Female Cancer Survivors: A Systematic Review and Meta-analysis

Improvements in cancer therapy for childhood and adolescent and young adult (AYA) survivors have increased in excess of 80% among pediatric patients and in excess of 85% among AYA cancer patients. Our research group explored the late effects consequences of cancer treatment on pregnancy and birth outcomes subsequent to a childhood (0-14 years) or AYA (15-25 years) diagnosis of cancer in female cancer survivors. Embase and Medline databases were searched. There were 17 review (n = 10 matched and n = 7 unmatched) studies that met the inclusion criteria. Subanalyses were conducted on 10 matched studies. The median age for all studies for patients at diagnosis and birth was 11 and 27 years, respectively. In matched cohort studies, female childhood and AYA cancer patients, who received chemotherapy alone, had a pooled estimated rate of 18% of experiencing a live birth compared with 10% of females who received radiotherapy alone and subsequently had a live birth. Females who received surgery alone reported higher pooled estimated rates of 44% for a live birth. For matched retrospective review studies, 79% (n = 973) of women experienced a live birth, of which 22% of these babies were born preterm. This meta-analysis found lower birth rates for survivors. Access to fertility-related information and discussions around fertility preservation options and oncofertility psychosocial support should be offered to all cancer patients and their families before starting cancer treatment.

Apheresis on aged patients/donors with complicated backgrounds like ischemic heart disease, arrhythmia, and others

Peripheral blood stem cells (PBSCs) are currently one of the most important stem cell sources for hematopoietic stem cell transplantation as well as cell therapy for ischemic heart disease or critical limb ischemia. Thus, it is sometimes necessary to collect autologous PBSCs from donors who have comorbidities. In terms yield, a sufficient number of PBSCs can be collected from donors with comorbidities for performing cell therapy if their age is < 60 years or up to a maximum of 70 years, although the number of PBSCs collected from older donors would probably be lower than that obtained from younger donors. On the other hand, granulocyte colony-stimulating factor (G-CSF) administration sometimes results in severe adverse events (AEs), such as ischemic heart disease and vascular thrombosis. Therefore, it is very important to perform strict medical check-ups according to the standards for donor operations in each country before apheresis. The apheresis procedure and G-CSF administration should be performed after administering the appropriate treatment. There is very less information available regarding AEs related to citrate administration during apheresis in aged donors with complicated medical histories. Medical staff should have knowledge of the electrocardiogram (ECG) QTc prolongation that occurs during apheresis owing to hypocalcemia caused by citrate administration, necessitating electrocardiographic monitoring of patients. Calcium should be administered during apheresis to prevent citrate related symptoms.

Trends in peripheral stem/progenitor cell manipulation and clinical application

Transplants using peripheral blood hemopoietic stem/progenitor (PBHS) cells are widely performed for the treatment of patients with hematologic disorders in routine practice and clinical trials. Although the process from mobilization to infusion of PBHS cells has been mostly established, optimal conditions for each process remain undetermined. Adverse reactions caused by PBHS cell infusions have not been systematically recorded. In transplants using PBHS cells, a number of problems still exist. In this section, the current status of and future perspectives regarding PBHS cells are described.

Bone marrow harvest in donors with anaemia

BACKGROUND

Bone marrow harvest (BMH) for haematopoietic stem cell transplantation is a well-established procedure. The guidelines of World Marrow Donor Association provide information on donor selection. However, some of the guidelines regarding donors with anaemia prior to harvest lack in supporting data from clinical studies. With this study, we aimed to provide such data.

MATERIAL AND METHODS

In this retrospective, single-centre study, we analysed the interplay between haemoglobin levels and BMH and BMH impact on haemoglobin levels in a cohort of 149 unrelated BM donors, including 13 subjects with mild anaemia.

RESULTS

The BMH led to significantly lower decrease in haemoglobin levels in donors with anaemia than in control group (1·79 g/dl vs. 2·56 g/dl, P < 0·0001). The following parameters: BMH volume (ml), BMH volume/donor body weight (ml/kg), total nucleated cells (TNC) in product (×10⁸ ) and TNC/kg recipient body weight in product (×10⁸ /kg) did not differ significantly between those two analysed groups (P > 0·05). Median BM volume harvested from anaemic donors was 16·34 ml/kg; none of them required blood transfusion after BMH.

CONCLUSION

Mild anaemia prior to BMH does not significantly impact the collection results. The BMH is safe and feasible in donors with mild anaemia.

Patients' Main Concerns About Having a Sibling Stem Cell Donor - A Grounded Theory Study

Background:

There is limited knowledge about the perspective of patients undergoing allogeneic haematopoietic stem cell transplantation (HSCT) about having a sibling as donor. It is essential to understand the main concerns of stem cell recipients in order to enable nurses to provide person-centred care.

Objectives:

The study aim was to explore patients’ main concerns about having a sibling stem cell donor and how the patients handle them, from immediately before until one year after transplantation.

Methods:

Twenty-eight interviews were performed prospectively during one year with ten adult sibling stem cell recipients with a mean age of 52 years (range 19-68 years). The interviews were analyzed by the Grounded Theory method.

Results:

The core category Recompensation summarises the process in the generated grounded theory including the three main categories; Invest, Compensate and Celebrate. Recompensation is defined as a lasting compensation given by the recipient to the sibling donor for the loss or harm suffered or effort made. The sense of having to reward, protect, appreciate, maintain peace and work on the relationship with the sibling donor at the same time as having to accept a serious illness, cope with their situation and promote their own recovery is strenuous for the recipients.

Conclusion:

The main concern for stem cell recipients during their first post-transplant year is to recompensate the sibling donor by investing, compensating and celebrating her/him. Although there is a positive aspect of recompensation, it can also imply pressure and guilt.

Bone marrow harvest from unrelated donors-up-to-date methodology

OBJECTIVES

Bone marrow harvesting is one of the essential sources of stem cells for hematopoietic stem cell transplantation. We describe here the current "up-to-date" standard of the bone marrow harvest in unrelated stem cell donors.

METHODS

We analyzed medical data of 187 unrelated hematopoietic stem cell donors who underwent bone marrow harvest without previous peripheral blood stem collection at the center between 2011 and 2015. The methodology of marrow collection includes multiple cells aimed at safety of the procedure, for example, educational movie, modified skin disinfection protocol, cell enumeration during the procedure, reduction of the contamination surfaces, and ongoing monitoring of the quality of work of the doctors.

RESULTS

The total nucleated cell count over 2×10⁸ per kg of recipient has been reached in 93.6% of harvests. All of the donors harvested more than 1×10⁸ per kg of the recipient. There were no donors who required transfusions or had serious adverse events during and after the harvest.

CONCLUSION

We describe here the current up-to-date standard of bone marrow harvest, which leads to excellent results in majority of donors without causing significant complications during the donation.

Medical and ethical considerations on hematopoietic stem cells mobilization for healthy donors

Hematopoietic stem cell transplantation is a common procedure potentially beneficial to many individuals with cancer, hematological, or inherited disorders, and has highlighted the need of related or unrelated donors to perform allograft. Donation of hematopoietic stem cells, either through bone marrow harvest or peripheral blood stem cell collection, is well-established and widespread. Over the past two decades, the peripheral blood stem cell collection by aphaeresis has become the main source of hematopoietic stem cells for transplantation, due to faster engraftment and practicability and lower risk of relapse for high-risk patients. For peripheral blood stem cell donation, donors require mobilization of hematopoietic stem cells from bone marrow into the blood stream. This is performed by growth factors injections. This article is a review of reported applications of growth factors (original granulocyte colony stimulating factor and its biosimilars), for healthy donors' peripheral blood stem cell mobilization, in terms of toxicity, side effects, efficacy and follow-up. There is still an ethical dilemma for clinicians involved in allograft, because they expose healthy donors to drugs. It is important to dispel some of the critical concerns regarding their use in healthy volunteers, particularly because they receive no personal therapeutic benefit from this procedure.

Plerixafor enables safe, rapid, efficient mobilization of hematopoietic stem cells in sickle cell disease patients after exchange transfusion

Sickle cell disease is characterized by chronic anemia and vaso-occlusive crises, which eventually lead to multi-organ damage and premature death. Hematopoietic stem cell transplantation is the only curative treatment but it is limited by toxicity and poor availability of HLA-compatible donors. A gene therapy approach based on the autologous transplantation of lentiviral-corrected hematopoietic stem and progenitor cells was shown to be efficacious in one patient. However, alterations of the bone marrow environment and properties of the red blood cells hamper the harvesting and immunoselection of patients' stem cells from bone marrow. The use of Filgrastim to mobilize large numbers of hematopoietic stem and progenitor cells into the circulation has been associated with severe adverse events in sickle cell patients. Thus, broader application of the gene therapy approach requires the development of alternative mobilization methods. We set up a phase I/II clinical trial whose primary objective was to assess the safety of a single injection of Plerixafor in sickle cell patients undergoing red blood cell exchange to decrease the hemoglobin S level to below 30%. The secondary objective was to measure the efficiency of mobilization and isolation of hematopoietic stem and progenitor cells. No adverse events were observed. Large numbers of CD34⁺ cells were mobilized extremely quickly. Importantly, the mobilized cells contained high numbers of hematopoietic stem cells, expressed high levels of stemness genes, and engrafted very efficiently in immunodeficient mice. Thus, Plerixafor can be safely used to mobilize hematopoietic stem cells in sickle cell patients; this finding opens up new avenues for treatment approaches based on gene addition and genome editing. Clinicaltrials.gov identifier: NCT02212535.