Healthy Related Donors Research Articles

The safety and efficacy of hematopoietic stem cell mobilization using biosimilar filgrastim in related donors.

In April 2014, the Japan Society for Hematopoietic Cell Transplantation started a prospective observational study entitled "A short-term follow-up investigation of related hematopoietic stem cell donors receiving biosimilar G-CSF to mobilize peripheral blood stem cells." A total of 106 donors were registered from 25 transplant facilities through the end of March 2017. The study cohort consisted of 47 men and 58 women, and their median age was 38.5years (range 15-65years). The mean total count of collected CD34-positive cells/recipient body weight for all 106 donors was 4.40 ± 2.38 × 10 6/kg. The yield of CD34-positive cells was weakly correlated with donor age was observed. However, gender, WBC count on day 4, G-CSF dose reduction, type of apheresis device, collection speed, and treated blood volume had no significant impact on the collection efficacy of CD34-positive cells. The safety profile of biosimilar G-CSF was also acceptable: 126 adverse events in 73 donors were reported, but none was serious. The most common adverse events were low back pain, headache, and bone pain. This prospective study confirmed that biosimilar G-CSF had comparable efficacy and safety to reference G-CSF for CD34-positive cell mobilization in healthy related donors.

A Single-Center Analysis of the Use of G-CSF Combined with Plerixafor to Mobilize Peripheral Blood Hematopoietic Stem Cell from Healthy Related Donors in Allogeneic Hematopoietic Stem Cell Transplantation

To study the effect and safety of G-CSF combined with Plerixafor on the mobilization of peripheral blood hematopoietic stem cells from healthy related donors of allogeneic hematopoietic stem cell transplantation (allo-HSCT). It was analyzed retrospectively that the data of peripheral blood hematopoietic stem cells from 33 (observation group) related donors mobilized by G-CSF plus Plerixafor in Hebei Yanda Lu Daopei Hospital from April 2019 to April 2021. Bone marrow and peripheral blood hematopoietic stem cells (PBSCs) of these donors were respectively collected on the fourth and fifth day of G-CSF-induced mobilization. Following the administration of Plerixafor on the night of the fifth day, PBSCs were collected on the sixth day once again. 46 donors using "G-CSF only" mobilization method in the same period were randomly selected as the control and respectively analyzed the differences of CD34+ cell counts on the fifth and the sixth day in two groups. And the donors' adverse reaction to Plerixafor in the form of questionnaire was also observed. Then it was compared that the patients who underwent allo-HSCT in "G-CSF+Plerixafor" group and "G-CSF only" group in terms of acute GVHD at grade I-IV or III-IV, CMV reactivation and EBV reactivation. CD34+ cells count (M±Q) among PBSCs collected on the fifth and the sixth day in the observation group were (1.71±1.02)×106/kg and (4.23±2.33)×106/kg, respectively. CD34+ cell counts on the sixth day was significantly higher than that of the fifth day (P<0.001); While the counterparts in the control group were (2.47±1.60)×106/kg and (1.87±1.37)×106/kg, respectively. By statistical analysis, CD34+ cell counts on the sixth day was significantly less than that of the fifth day (P<0.001). The adverse reaction to Plerixafor for the donors in the study were all grade 1 or 2 (mild or moderate) according to CTCAE 5.0 and disappeared in a short time. The patients who underwent allo-HSCT in the "G-CSF+Plerixafor" group and "G-CSF only" group were not statistically significant in terms of acute GVHD at grade I-IV or III-IV, CMV reactivation and EBV reactivation (P>0.1). The cell mobilization program of G-CSF combined with Plerixafor is safe and effective for being applied to allo-HSCT. The addition of Plerixafor can significantly increase the number of CD34 postive cells in the PBSC collection. Key words ; ;

Hope for progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy is a rare but important brain disease caused by JC virus. This polyomavirus typically causes an asymptomatic infection in healthy people. In a few individuals with chronic cellular immunodeficiency, JC virus evolves to become neurotropic, infecting and killing oligodendrocytes to cause a subacute progressive demyelinating disease that generally is fatal within 6 months from symptom onset. 1 Major EO Yousry TA Clifford DB Pathogenesis of progressive multifocal leukoencephalopathy and risks associated with treatments for multiple sclerosis: a decade of lessons learned. Lancet Neurol. 2018; 17: 467-480 Summary Full Text Full Text PDF PubMed Scopus (104) Google Scholar BK virus-specific T cells for immunotherapy of progressive multifocal leukoencephalopathy: an open-label, single-cohort pilot studyWe showed that generation of polyomavirus-specific T cells from healthy related donors is feasible, and these cells can be safely used as an infusion for adoptive immunotherapy of progressive multifocal leukoencephalopathy. Although not powered to assess efficacy, our data provide additional support for this strategy as a potential life-saving therapy for some patients. Full-Text PDF

BK virus-specific T cells for immunotherapy of progressive multifocal leukoencephalopathy: an open-label, single-cohort pilot study

Progressive multifocal leukoencephalopathy, a rare disease of the CNS caused by JC virus and occurring in immunosuppressed people, is typically fatal unless adaptive immunity is restored. JC virus is a member of the human polyomavirus family and is closely related to the BK virus. We hypothesised that use of partly HLA-matched donor-derived BK virus-specific T cells for immunotherapy in progressive multifocal leukoencephalopathy would be feasible and safe. We did an open-label, single-cohort pilot study in patients (aged 18 years or older) with clinically definite progressive multifocal leukoencephalopathy and disease progression in the previous month at the National Institutes of Health (NIH) Clinical Center (Bethesda, MD, USA). Overlapping peptide libraries derived from large T antigen and major capsid protein VP1 of BK virus with high sequence homology to JC virus counterparts were used to generate polyomavirus-specific T cells cross-recognising JC virus antigens. Polyomavirus-specific T cells were manufactured from peripheral blood mononuclear cells of first-degree relative donors aged 18 years or older. These cells were administered to patients by intravenous infusion at 1 × 106 polyomavirus-specific T cells per kg, followed by up to two additional infusions at 2 × 106 polyomavirus-specific T cells per kg. The primary endpoints were feasibility (no manufacturing failure based on meeting release criteria, achieving adequate numbers of cell product for clinical use, and showing measurable antiviral activity) and safety in all patients. The safety monitoring period was 28 days after each infusion. Patients were followed up with serial MRI for up to 12 months after the final infusion. This trial is registered at ClinicalTrials.gov, NCT02694783. Between April 7, 2016, and Oct 19, 2018, 26 patients were screened, of whom 12 were confirmed eligible and received treatment derived from 14 matched donors. All administered polyomavirus-specific T cells met the release criteria and recognised cognate antigens in vitro. 12 patients received at least one infusion, ten received at least two, and seven received a total of three infusions. The median on-study follow-up was 109·5 days (range 23-699). All infusions were tolerated well, and no serious treatment-related adverse events were observed. Seven patients survived progressive multifocal leukoencephalopathy for longer than 1 year after the first infusion, whereas five died of progressive multifocal leukoencephalopathy within 3 months. We showed that generation of polyomavirus-specific T cells from healthy related donors is feasible, and these cells can be safely used as an infusion for adoptive immunotherapy of progressive multifocal leukoencephalopathy. Although not powered to assess efficacy, our data provide additional support for this strategy as a potential life-saving therapy for some patients. Intramural Research Program of the National Institute of Neurological Disorders and Stroke of the NIH.

Addition of plerixafor to G-CSF in poor mobilizing healthy related donors overcame mobilization failure: An observational case series on behalf of the Grupo Español de Trasplante Hematopoyético (GETH)

Plerixafor (Mozobil, Sanofi) is approved for using in patients with lymphoma and multiple myeloma when steady-state mobilization strategies fail. Although off-label use of plerixafor in healthy related donors (HRD) is known, limited data are available and no recommendations exist to guide its use in this setting. With the aim of collecting data from HRDs who received plerixafor in our country, we designed an observational case series study within the Spanish Group of Hematopoietic Transplant and Cell Therapy (GETH). Plerixafor was administered subcutaneously to 30 HRDs at a median dose of 0.24 mg/Kg (interquartile range (IQR): 0.23−0.25) because mobilization failure after using mobilization with G-CSF (mobilization failure was defined as collection of <4.0 × 106 CD34+ cells/Kg recipient). All HRDs received G-CSF at a median dose of 11 μg/Kg/day (IQR: 10–12) for 4–5 days. Leukocytapheresis after G-CSF mobilization was performed in 23 (77 %) HRDs collecting a median of 1.6 × 106 CD34+ cells/Kg recipient weight (IQR: 0.9–2.5). Addition of plerixafor allowed the collection of a higher median number of CD34 cells (4.98 × 106 CD34+ cells/Kg recipient weight (IQR: 3.5–5.8)) when compared with the collection of CD34+ cells with G-CSF alone (p < 0.01). The final median total number of CD34+ cells collected was 6.1 × 106/Kg recipient weight (IQR: 4.8–7.3). Mild adverse events related with plerixafor administration were reported in 8 (27 %) donors. In conclusion, addition of plerixafor after G-CSF mobilization failure in HRDs allowed collecting higher number of CD34+ cells in comparison with steady-state mobilization.

Analysis of a large single institution cohort of related donors fails to detect a relation between SDF1/CXCR4 or VCAM/VLA4 genetic polymorphisms and the level of hematopoietic progenitor cell mobilization in response to G-CSF.

We studied a cohort of 367 healthy related donors who volunteered to donate their hematopoietic stem cells for allogeneic transplantation. All donors were homogeneously cared for at a single institution, and received rhG-CSF as a mobilization treatment prior to undergoing apheresis. Peripheral blood CD34+ cell counts were used as the main surrogate marker for rhG-CSF induced mobilization. We searched whether inter-individual variations in known genetic polymorphisms located in genes whose products are functionally important for mobilization, could affect the extent of CD34+ mobilization, either individually or in combination. We found little or no influence of individual SNPs or haplotypes for the SDF1, CXCR4, VCAM and VLA4 genes, whether using CD34+ cell counts as a continuous or a categorical variable. Simple clinical characteristics describing donors such as body mass index, age and possibly sex are more potent predictors of stem cell mobilization. The size of our cohort remains relatively small for genetic analyses, however compares favorably with cohorts analyzed in previously published reports suggesting associations of genetic traits to response to rhG-CSF; notwithstanding this limitation, our data do not support the use of genetic analyses when the choice exists of several potential donors for a given patient.

A matched-pair analysis reveals marginally reduced CD34+ cell mobilization on second occasion in 27 related donors who underwent peripheral blood stem cell collection twice at the same institution.

In a small proportion of cases, hematopoietic function is insufficient after allogeneic hematopoietic stem cell transplantation, as a result of poor graft function or graft failure. These complications are common indications of re-mobilization of the initial donor, either for a second allograft or for an infusion of CD34+ Selected stem Cell Boost (SCB). We retrospectively reviewed the results of two cycles of CD34+ cell mobilization and collection. CD34+ cells mobilized and collected at each cycle were compared. When CD34+ cell selection from the collected allogeneic mononuclear cells was indicated, it was performed with the Clinimacs Plus® medical device, and results from in-process and final quality checks were analyzed. To assess the efficacy of CD34+ SCB, transfusion needs before and after the infusion of selected CD34+ cells were calculated. The median peripheral blood concentration of CD34+ cells/μL was marginally reduced during the second cycle (35.6 vs 33.8, p < 0.05); results revealed a strong correlation between paired values (r = 0.85). The cumulative number of collected CD34+ cells were similar for both cycles; the total processed blood volume was higher during the second cycle (p = 0.023). For CD34+ immune-selection procedures, CD34+ cell recovery and purity were respectively 57% and 95%, with a median T-cell depletion of 6.7 log. Recipients' needs for platelet and red blood cell transfusions were significantly reduced after CD34+ SCB. This study confirms the feasibility of a second cycle of mobilization in healthy related donors and the benefits of CD34+ SCB on hematopoietic reconstitution.

Clonal Hematopoiesis in Related Allogeneic Transplant Donors: Implications for Screening and Management

Background: In hematopoietic cell transplantation (HCT), there is an increasing recognition of the risks of transferring clonal hematopoiesis from donors to recipients. It is unknown whether HCT centres screen for clonal hematopoiesis in related donors (RDs), and how such findings are managed. Methods: We conducted an international survey of 609 HCT centers to understand if HCT centres screen for CH, and whether candidates with this finding are excluded from donation. The survey consisted of questions about their approach to assessing otherwise healthy RDs with normal blood counts. Findings: The response rate was 280/609 (46%). Routine testing for CH is performed for monoclonal gammopathy of undetermined significance [MGUS] (18.9% of centres), monoclonal B-cell lymphocytosis [MBL] (5.0%), and gene sequencing for somatic mutations (3.6%). Bone marrow biopsies are performed in healthy RDs in 6% of responding centres, with an additional 6.7% performing this test in sub-groups, especially in older donors. Respondents recalled detecting at least one case of MGUS (17.8% of respondents), MBL (9.9%) or cytogenetic abnormalities (7.7%). Donor deferral was recommended in 62% of respondents if there were findings of MGUS, 60.4% for MBL, 74% for clonal cytogenetics, and 62.8% for somatic mutations. Interpretation: An appreciable proportion of HCT centres routinely screen for disorders of CH in blood or marrow from RDs. There is uncertainty about whether CH constitutes grounds for donor exclusion. We recommend the development of guidelines and standardization of screening for CH. Funding: Center for International Blood and Marrow Transplantation (CIBMTR) and National Marrow Donor Program (NMDP). Declaration of Interest: Dr Seftel reports reports grants from Teva, personal fees from Shire, personal fees from Pfizer, personal fees from Jazz, personal fees from Amgen, outside the submitted work. Mr. Logan does not have any competing interests. Dr. Shah does not have any competing interests. Dr. Confer does not have any competing interests. Dr. Shaw does not have any competing interests. Dr. Switzer does not have any competing interests. Dr. Pulsipher does not have any competing interests. Ms. Kiefer does not have any competing interests. Ms. Kuxhausen does not have any competing interests. Dr. Lee does not have any competing interests. Dr. Burns does not have any competing interests. Dr. Chitphakdithai does not have any competing interests. Dr. O’Donnell does not have any competing interests. Ethical Approval: This survey was approved by the National Marrow Donor Program.

A Pilot Study of Adoptive Cellular Immunotherapy for Progressive Multifocal Leukoencephalopathy with Ex Vivo Generated Polyomavirus-Specific T-Cells

▪Background: Progressive Multifocal Encephalopathy (PML) is a subacute infection of the central nervous system (CNS) mediated by John Cunningham (JC) polyomavirus (PyV). The disease is frequently fatal, unless adaptive immunity to JC virus is restored. The disease typically occurs in immunosuppressed patients (e.g. HIV/AIDS). In the modern era, patients with hematological malignancies treated with rituximab and/or fludarabine or following immunosuppressive therapy for transplant or autoimmunity (e.g. multiple sclerosis (MS) or Crohn's disease) are also at risk. JC-PML can also occur in patients with genetic defects of immunity. Specific treatments do not exist and immunocompromised patients with history of cancer or genetic defects of immunity have no realistic chance for rapid recovery of their ability to fight infections. In subjects with Rituximab-related PML the case-fatality ratio is >90%. Survivors can be left with severe neurological disabilities.Methods: Based on our previously established procedure for generation of multi-virus virus-specific T cells using overlapping peptide libraries (pepmixes) as immunogens, we have developed dedicated polyomavirus-specific T cells (PyVST) targeting polyomavirus BK large T (LT) and Viral Protein 1 (VP1) antigens and highly cross-reactive with the structurally-homologous JC LT and VP1 proteins (see Figure). We hypothesized that adoptive transfer of donor-derived PyVSTs could be safely used for therapy of patients with refractory JC-PML. We have developed a pilot study to test the feasibility and safety of adoptive immunotherapy strategy using PyVSTs from the partially matched healthy 1st degree relative donors (sibling, parent or offspring; NIH study 16-N-0072). Adults diagnosed with PML who have no other treatment options were eligible. Patients with MS or HIV were excluded. PyVSTs were generated from donor blood leukocytes cultured for 14 days in G-rex flasks upon stimulation with BK LT and VP1 pepmixes. Subjects underwent baseline physical examination, MRI and lumbar puncture. Upon enrollment subjects received an intravenous infusion of a fixed dose of 1x10e6 (+/-10%) PyVST cells/kg. Safety monitoring period was 28 days after each infusion. Subjects were eligible for up to two additional infusions (dose 2x10e6 PyVSTs/kg) a minimum of 28 days apart if no toxicities were observed. Serial MRI and lumbar punctures were performed to monitor response. Subjects were followed for 12 months after the last infusion.Results: Nine subjects have been enrolled and treated with at least one infusion of PyVSTs under this protocol and the trial is still accruing subjects. No immediate infusion reactions or adverse events have been observed within the safety monitoring period. No CNS immune system reconstitution syndrome (IRIS) has occurred. One subject received a single infusion and withdrew from the study following Day 14 visit due to unwillingness to travel. One subject received two doses of PyVSTs with stabilization of the disease, not requiring the 3rd infusion. This subject was withdrawn from the study just prior to the 1 year follow up visit, as he was diagnosed with the stage IV lung cancer and entered hospice. Seven subjects received 3 infusions of PyVSTs. 3 of these 7 patients died of refractory PML, all >30 days after the 3rd dose of T cells. At the time of this report one subject completed the study at one year with stable PML. The remaining subjects are in the follow-up phase of the protocol.Conclusions: We report that partially matched T cells targeting PyVs generated from healthy related donors can be safely used for adoptive immunotherapy of severely immunocompromised patients with PML. Multiple infusions of T cells are very well tolerated at the doses of up to 2x10e6 PyVST cells/kg, displaying excellent safety profile without adverse events. Furthermore, our data suggest possible efficacy of this strategy as a life-saving therapy for patients who otherwise face a dismal prognosis. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Cyclosporine May Inhibit the Effect of Extra-Physiologic Oxygen Shock/Stress on Peripheral Blood Stem Cells

Introduction: Adequate numbers of stem cells with preserved multi-potency and self-renewing capabilities are necessary for successful hematopoietic reconstitution after bone marrow transplantation. Although hematopoietic stem cells (HSC) reside in the bone marrow under a hypoxic microenvironment (1-4% O2), human HSC are collected and processed in ambient air (21% O2) (Spencer et al., Nature 508:269-73). Exposure of murine bone marrow and human cord blood to ambient air for as little as 30 minutes triggered stem cell differentiation from quiescent pluripotent long term stem cells into activated multipotent progenitors (MPPs), a phenomenon called extra-physiologic oxygen shock / stress (EPHOSS)(Mantel et al., Cell 161:1553-65). The effect of EPHOSS on HSCs is mediated through reactive oxygen species (ROS) which open the mitochondrial permeability transition pore (MPTP) and trigger stem cell differentiation. Cyclosporine (CSA) inhibits the MPTP regulator cyclophilin D and prevents MPTP opening (Kroemer et al., Physiol Rev 87:99-163). Currently, mobilized peripheral blood stem cells (PBSCs) are the major source of grafts for hematopoietic cell transplantation. We hypothesized that EPHOSS is detrimental to human PBSCs similar to murine bone marrow and human cord blood stem cells and CSA will protect human PBSCs from the effects of EPHOSS and inhibit their differentiation from pluripotent long term HSC into short term MPPs.Study design and methods. This is a proof-of-concept, prospective, non-interventional study. We obtained G-CSF mobilized PBSCs from healthy related donors under an IRB approved protocol. All donors provided written informed consent. Blood containing HSCs was collected from each donor with minimal exposure to ambient air (<60 seconds). The sample was immediately split and incubated for 60 minutes with and without CSA (50 µg/mL). CSA treated and untreated PBSCs were immunophenotyped by multi-parameter flow cytometry for HSCs (CD34+CD38-CD90+CD45RA-), MPP (CD34+CD38-CD90-CD45RA-) and common lymphoid progenitors (CD34+CD38+CD127+). We used a CD34 ISHAGE-based gating strategy to accurately enumerate HSC and MPP.Results. In four separate experiments, CSA treated PBSCs had a higher median (range) number of HSCs/106 total nucleated cells (TNC) compared to untreated PBSCs ((297 (51 - 512) versus 185 (47 -392), respectively). CSA treated PBSCs also had a higher median (range) HSC:MPP ratio compared to untreated PBSCs ((0.56 (0.40 - 0.70) versus 0.43 (0.30 - 0.50), respectively) suggesting that the differentiation of HSC to MPP upon exposure to air was decreased in the CSA treated PBSCs.Conclusions / future directions. This is the first report describing the effect of EPHOSS in human PBSCs. Our preliminary data suggest that EPHOSS promotes the differentiation of human PBSCs from HSC to MPP and that CSA may inhibit this process. Further confirmatory and mechanistic studies exploring the contribution of MPTP and ROS to EPHOSS are ongoing. The results from this research may potentially change the current practice of collecting PBSCs in ambient air. DisclosuresMcCarthy:Janssen: Consultancy, Honoraria; Bristol Myers Squibb: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria. Chen:Bellicum Pharmaceuticals: Research Funding.

Metabolomics Profiling after Allogeneic Hematopoietic Stem Cell Transplantation Unravels a Specific Signature in Human Acute GVHD

IntroductionMany efforts have been attempted to improve our understanding of GVHD pathophysiology but few focused on human GVHD. Most studies have focused on the central role played by immune cells. However, recent researches have highlighted the influence of tissue microenvironment or of host microbiota in regulating allo-immune response. In human, circulating metabolites are produced by both tissues and gut microbiota. Among them, many biochemical compounds regulate immune cells function and could be the bridge between microbiota, tissues and the immune system. The aim of this study was to characterize metabolomics alterations associated with allo-HSCT and to determine biochemical pathway specifically involved during acute GVHD.MethodsWe collected donors and recipients' frozen plasma from a monocentric (n=43) and a multicentric cohort (n=56) of patients who underwent transplantation from an HLA-identical sibling in France. Donors' samples were collected before stem cell collection. Recipient's samples were obtained at acute GVHD onset or at day + 90 in patients without GVHD. After protein removal, plasma extracts were analyzed by two separate reverse phase (RP)/UPLC-MS/MS methods with positive ion mode electrospray ionization (ESI), one for analysis by RP/UPLC-MS/MS with negative ion mode ESI and one for analysis by HILIC/UPLC-MS/MS with negative ion mode ESI. Compounds were identified by comparison to library entries of purified standards or recurrent unknown entities. Peaks were quantified using area-under-the-curve. All statistical analyses were performed with R 3.5.0 and the MetaboAnalystR package.ResultsMore than 800 circulating metabolites were identified in the 2 cohorts, belonging to lipid (43.6%), amino acid (22.2%), xenobiotics (19.1%), nucleotide (4.2%), carbohydrate (3.6%), cofactors and vitamins (3.4%), peptide (2.8%) and energy (1.1%) pathways. After allo-HSCT, the comparison of metabolomics profiles of recipients without GVHD with those of healthy related donors revealed major changes in 222 metabolites (with a significance threshold at p<0.05). SAM and Volcano Plot analysis (with a fold change (FC) > 2 and p<0.05) highlighted significant modification in 43 metabolites. In the absence of acute GvHD, allo-HSCT was mainly characterized by a higher level of primary bile acids, mono and diacylglycerol, but a decrease of phospholipid, sphingolipid and secondary bile acid metabolites. Interestingly, polyamine, including N-acetyl putrescine (FC=5.5, p<0.001) and N-acetyl spermidine (FC=3.7, p<0.0001), were increased, suggesting that these microbiota-derived metabolites might play a protective role on gut integrity in patients without GVHD.After comparison of recipients with or without GvHD, we were able to identify specific metabolomics changes associated with the onset of GvHD, irrespective of age, sex and feeding of patients. Acute GvHD was associated with a major decrease of plasmalogen and lysoplasmalogen (FC<0.5, p<0.0001), that may play a role in protection against oxidative stress induced by ROS. By contrast, medium and long chain fatty and polyunsaturated acid were strongly increased (FC>2, p<0.01). Most metabolites of amino acid pathways were decreased at onset of acute GvHD. Among them, Aryl Hydrocarbon receptor ligands were diminished in patients with GvHD, especially host- and microbiota-derived tryptophan metabolites such as 3-indoxyl sulfate (p=0.0001), indole acetate (p=0.03), indole propionate (p=0.03) and N-acetyl kynurenine (p=0.04). Many other gut microbiota-derived metabolites were significantly decreased in patients with GvHD, suggesting that major microbiota injury after allo-HSCT may regulate allo-immune responses through the production of metabolites with immunomodulatory properties.DiscussionOur results demonstrate that allo-HSCT is associated with major metabolomics changes in recipients, which might me due to drug intakes, metabolic stress or microbiota alteration. GvHD was characterized by specific changes in complex lipid metabolism and amino acid metabolites that are involved in immune cells regulation and inflammation. This study highlights the potential role of circulating metabolites in GvHD pathophysiology that could be targeted for prophylaxis or treatment. DisclosuresPeffault De Latour:Pfizer Inc.: Consultancy, Honoraria, Research Funding; Alexion Pharmaceuticals, Inc.: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Amgen Inc.: Research Funding.

Factors associated with bone marrow stem cell yield for pediatric allogeneic stem cell transplantation: The impact of donor characteristics.

The aim of this study was to investigate the effects of donor characteristics on CD34+ cell yield in BM harvest. Between April 2010 and November 2013, consecutive donors who underwent BM harvesting in our BM transplantation unit were retrospectively investigated. Donors were classified into two groups: those who donated BM without mobilization (steady-state BM donors) and those who received G-CSF for stem cell mobilization (G-CSF-primed BM donors). Donor characteristics (age, gender, race, body weight, BMI, and laboratory factors including donor's leukocyte, platelet, and monocyte) and their relationship with total nuclear cell and CD34+ cell numbers has been evaluated. A total of 64 healthy related donors (29 males/35 females, median age 11.2years; 49 [76.6%] younger than 18 and 36 [56.3%] younger than 12years) were included in the study. The median CD34+ cell yield in the harvest was 0.12×106 /L (0.02-0.21) in SS-BM donors and 0.18×106 /L (0.09-0.67) in GP-BM donors (P=.03). Median of CD34+ cell count given to recipients was 2.6×106 /recipient body weight (1.3-19.3) in SS-BM yields and 3.8×106 /recipient body weight (1.1-10.2) in GP-BM yields, respectively. Multiple regression analysis showed that donor height and pre-G-CSF platelet were the most important parameters to obtain a sufficient BM harvest. Our data suggest that the shorter donors and the donors with higher thrombocyte counts may offer more hematopoietic stem cell. The height and thrombocyte count of the donors should be taken into consideration before planning the targeted CD34+ cell count especially for pediatric donors.

Mobilization and engraftment of peripheral blood stem cells in healthy related donors >55 years old

Background aimsThe increasing scarcity of young related donors has led to the use of older donors for related allogeneic hematopoietic stem cell transplantation (HSCT). This study analyzed the influence of age on the results of mobilization of peripheral blood stem cells (PBSCs) in healthy donors as well as on the engraftment and outcome of HSCT. MethodsA retrospective analysis from a single center was performed comparing the results of PBSC mobilization from related healthy donors according to their age. ResultsThe study included 133 consecutive related donors. The median age was 50 years (range, 4–77 years); 70 (53%) donors were males, and 44 (33%) were >55 years old. All donors were mobilized with granulocyte colony-stimulating factor for 5 days. The peak CD34+ cell count in peripheral blood was higher in younger than in older donors (median, 90.5 CD34+ cells/μL [range, 18–240 CD34+ cells/μL] versus 72 CD34+ cells/μL [range, 20–172.5 CD34+ cells/μL], P = 0.008). The volume processed was lower in younger than in older donors (16,131 mL [range, 4424–36,906 mL] versus 18,653 mL [range, 10,003–26,261 mL], P = 0.002) with similar CD34+ cells collected (579.3 × 106 cells [range, 135.14 × 106–1557.24 × 106 cells] versus 513.69 × 106 cells [range, 149.81 × 106–1290 × 106 cells], P = 0.844). There were no differences in time to recovery of neutrophils and platelets or in the incidences of acute and chronic graft-versus-host disease, overall survival, non-relapse mortality and relapse incidence. ConclusionsDonors >55 years old mobilized fewer CD34+ cells and required a greater volume to collect a similar number of CD34+ cells. The outcome of HSCT was not influenced by donor age. Donor age should not be a limitation for related allogeneic HSCT.

Allogeneic Serum Eye Drops for the Treatment of Dry Eye Patients with Chronic Graft-Versus-Host Disease

To evaluate the therapeutic effect of allogeneic serum eye drops for the treatment of dry eye in patients with chronic graft-versus-host disease (cGVHD) following bone marrow transplantation. Sixteen patients with cGVHD following allogeneic hematological stem cell transplantation (allo-SCT) and diagnosed with dry eye syndrome refractory to conventional treatment were prospectively enrolled in this study. Allogeneic serum eye drops were obtained from healthy related donors after serologic testing. Symptom scores, tear breakup time (tBUT), the Schirmer test without anesthesia (Schirmer I test), tear osmolarity, corneal staining score, impression cytology grade, and goblet cell densities were evaluated before and 4 weeks after administration of allogeneic serum eye drops. Enrolled patients included 6 females and 10 males between 20 and 61 years of age (mean age, 37.2±11.6 years). After 4 weeks of treatment, the Ocular Surface Disease Index (OSDI) symptom scores decreased significantly (32.5-8.9). Tear osmolarity showed a significant decrease from 311.1 to 285.1 milliosmol. The corneal staining scores significantly decreased from 2.5 to 1.8. Impression cytology grade and goblet cell density improved from 3.4 to 2.4 and from 90.6 to 122.6 cell/mm(2), respectively. tBUT also significantly improved from 2.9 to 4.4 s, and the Schirmer I test results showed improvement, but lacked statistical significance (1.7-2.4 mm). No significant side effects were detected as a result of the allogeneic serum treatment during the follow-up period. Allogeneic serum can be used for the treatment of severe dry eye in patients with cGVHD when autologous serum is unavailable. Care should be taken to avoid the risk of blood-borne diseases.

Safeguarding the long-term health of hematopoietic stem cell donors: a continuous and evolving process to maintain donor safety and trust

Safeguarding the long-term health of hematopoietic stem cell donors: a continuous and evolving process to maintain donor safety and trust

First Reported Use of a Biosimilar G-CSF in Allogeneic Stem Cell Mobilisation

Abstract 4571 OBJECTIVES:Biosimilar granulocyte colony-stimulating factor (G-CSF) has been approved on the basis of comparable quality, safety and efficacy as the originator product. Approval of biosimilar G-CSF is in the same indications as the originator, including autologous and allogeneic peripheral blood stem cell (PBSC) mobilisation, for which it is being used throughout our large hospital group in Paris, France. Concerns have been raised by professional bodies over use of biosimilar G-CSF in allogeneic transplants. To our knowledge, this is the first reported use of biosimilar G-CSF in healthy donors for allogeneic transplantation. METHODS:Healthy related donors received biosimilar G-CSF (EP-2006, Sandoz Biopharmaceuticals) 10 μg/kg/day for PBSC mobilisation. G-CSF was administered on days 1–4 with the first leukapheresis performed on day 5. If the required number of CD34+ cells per recipient body weight (4 × 106 CD34+ cells/kg) was not collected, G-CSF administration was continued and a second PBSC collection was performed on day 6. Further G-CSF administration and a third leukapheresis was done on day 7 if required. RESULTS:Twelve healthy donors (7 male, 5 female; mean ± SD age 61.0 ± 7.8 years, range 51–73) received biosimilar G-CSF for PBSC mobilisation. Median donor body weight was 82 kg (range 55–115 kg). Median CD34+ cell count on day 5 was 75/ml (range 23–140). A single leukapheresis after 4 injections of biosimilar G-CSF was sufficient to collect the CD34+ cell dose required in six donors with peripheral blood (PB) CD34+ counts ranging from 80–140 ml. Six donors underwent a second leukapheresis after 5 days of biosimilar G-CSF, one of whom (a 73-year old female) underwent a third leukaphereses on day 7 (PB CD34+ at first apheresis 23 ml). Median number of CD34+ cells per recipient bodyweight was 5.5 × 106 cells/kg (range 2.6–8.9). Five donors reported bone pain (4 mild, 1 moderate severity) which was effectively treated with paracetamol. No other adverse events were reported. Blood measurements were normal in all donors when assessed one week after the end of mobilisation. These findings are consistent with our previous use of originator G-CSF (Neupogen®) in allogeneic stem cell mobilisation. CONCLUSION:These preliminary findings suggest biosimilar G-CSF is effective and well-tolerated in allogeneic stem cell mobilisation. Further studies are required to assess longer-term safety outcomes. The use of biosimilar G-CSF may provide important cost-savings when compared with the originator product. Disclosures:No relevant conflicts of interest to declare.

Risk and prevention of graft failure in patients with preexisting donor-specific HLA antibodies undergoing unmanipulated haploidentical SCT

A role of donor-specific HLA antibodies (DSA) in graft failure after SCT has been suggested, but the relevance of DSA in unmanipulated haploidentical SCT (haplo-SCT) remains unknown. We prospectively examined HLA antibodies using the Luminex-based single Ag assay for 79 adult patients undergoing unmanipulated haplo-SCT. Among them, 16 (20.2%) were HLA Ab-positive, including five patients with antibodies not corresponding to donor HLA Ags and 11 DSA-positive patients. Of the 11 DSA-positive patients, five received treatments to decrease DSA levels, including two, who received plasma exchange and rituximab, two who received platelet transfusions from healthy-related donors having DSA-corresponding HLA Ags and one who received bortezomib. Platelet transfusion was the most simple and effective treatment option for class I DSA. The cumulative incidence of neutrophil recovery was significantly lower in pretransplant (post-treatment) DSA-positive patients than in DSA-negative patients (61.9 vs 94.4%, P=0.026). Notably, three of five patients with high levels of DSA had graft failure. Donors should be selected on the basis of an evaluation of HLA antibodies. If haplo-SCT from donors with HLA Ags that correspond to high levels of DSA must be performed, then recipients should be treated for DSA to improve the chances of successful donor engraftment.

Comparative Single-Institute Analysis of Cord Blood Transplantation From Unrelated Donors with Related Bone Marrow or Peripheral Blood Stem-Cell Transplants in Elderly Patients with Hematologic Diseases After Reduced Intensity-Conditioning Regimen.

Abstract 2295Poster Board II-272 Introduction:Allogeneic hematopoietic stem cell transplantation with reduced-intensity conditioning has been widely applied to those who have advanced hematologic diseases and are not eligible for conventional conditioning. Although bone marrow or peripheral blood from related donors (rBM/PB) have been the first choice of graft when available, followed by unrelated adult donor or cord blood (CB), true superiority of rBM/PB over others can still be controversial. Elderly patients have difficulty finding related donors since their siblings are also in their elderly who have higher chance of having co-morbidity relative to younger patients. Rapid availability is the advantage of rBM/PB and CB share over unrelated adult donor, which enabled adapting similar policy of performing transplant possible, especially for elderly patients, given the significantly higher treatment-related mortality for elderly. Design and Methods:We retrospectively reviewed patients aged 55 and older who underwent reduced intensity allogeneic stem-cell transplantation using CB or rBM/PB at our institute from Jan. 2004 to Dec. 2008 consecutively. Patients who were considered for allogeneic transplant and had available 6/6 or 5/6 HLA-matched relatives performed rBM/PB transplants, whereas those who lacked rBM/PB donors underwent CB transplants. Patients who had prior history of transplantation, were in poor performance status (ECOG PS 2 and greater), had active bacterial or fungal infections at the time of conditioning, had diagnosed as multiple myeloma, adult T-cell leukemia, non-malignant diseases were excluded. Results:Two-hundred and thirty-two (171 CB and 60 rBM/PB) RI transplantation were performed from Jan. 2004 to Dec. 2008 at our institute, and 82 (61 CB and 21 rBM/PB) were eventually subjected to the analysis after excluding those who were ineligible according to the above mentioned criteria. The diagnoses included were AML (n=51), MDS (n=9), ALL (n=9) CML/MPD (n=4), and ML (n=9). Fifty-eight (71%) had high risk diseases, and 24 (29%) were in ECOG PS 2. Recipients of CB and rBM/PB were comparable in terms of diagnosis, disease risk (standard vs high), ECOG PS (0-1 vs 2), and year of transplant (2004-2005 vs 2006-2008). The median age for rBM/PB recipients was slightly younger (median 60, range 55-66) than that for CB (median 62, range 55-69, P < .03). CB recipients received more serologically HLA-mismatched grafts (98% vs. 3%, P<.0001), had shorter duration of donor search (median 43 days vs. 148 days, P<.0001), were conditioned more frequently with fludarabine/melphalan/TBI regimen (70% vs. 5%, P<.0001), used more tacrolimus (100% vs. 29%) and less methotrexate (0% vs. 100%, P<.0001) for GVHD prophylaxis, compared to rBM/PB recipients. Median follow-up time of survivors were 766 (25-1769) days for CB and 824 (173-1345) for rBM/PB recipients respectively. CB recipients showed slower neutrophil recovery (median 21 (12-43) days vs. 15 (11-21) days), and lower rate of myeloid engratment (75% vs. 100%, P<.01). The overall (OS) and event-free survival (EFS) at 2 years post-transplant showed no statistically significant differences between CB (OS 29+/-6% and EFS 23+/-6%) and rBM/PB recipients (OS 37+/-12% and EFS 29+/-11%). 23/43 (47%) CB recipients' death was due to non-relapse causes, whereas 9/12 (75%) rBM/PB recipients' death was due to relapse. Cumulative incidences of relapse at 2 years were 44+/-0.5% for CB and 49+/-1.4% for rBM/PB recipients (N.S.). Conclusions:These data suggest that, for elderly patients, comparable results can be expected using CB, which opens more opportunity for elderly patients to undergo allogeneic transplants who generally have difficulty finding healthy related donors compared to younger patients. However, before CB become the first choice of graft, higher rate of engraftment failure and non-relapse mortality, particularly during early period post-transplant, need to be overcome, and, at this moment, rBM/PB is still the optimal graft of choice when available over CB. Disclosures:No relevant conflicts of interest to declare.