scholarly journals Inducible SBDS Deficiency Impairs Bone Marrow Niche Function to Engraft Donor Hematopoietic Stem Cell after Transplantation

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3199-3199
Author(s):  
Ji Zha ◽  
Lori Kunselman ◽  
Hongbo Michael Xie ◽  
Brian Ennis ◽  
Jian-Meng Fan ◽  
...  

Hematopoietic stem cell (HSC) transplantation (HSCT) is required for curative therapy for patients with high-risk hematologic malignancies, and a number of non-malignant disorders including inherited bone marrow failure syndromes (iBMFS). Strategies to enhance bone marrow (BM) niche capacity to engraft donor HSC have the potential to improve HSCT outcome by decreasing graft failure rates and enabling reduction in conditioning intensity and regimen-associated complications. Several studies in animal models of iBMFS have demonstrated that BM niche dysfunction contributes to both the pathogenesis of iBMFS, as well as impaired graft function after HSCT. We hypothesize that such iBMFS mouse models are useful tools for discovering targetable niche elements critical for donor engraftment after HSCT. Here, we report the development of a novel mouse model of Shwachman-Diamond Syndrome (SDS) driven by conditional Sbds deletion, which demonstrates profound impairment of healthy donor hematopoietic engraftment after HSCT due to pathway-specific dysfunctional signaling within SBDS-deficient recipient niches. We first attempted to delete Sbds specifically in mature osteoblasts by crossing Sbdsfl/flmice with Col1a1Cre+mice. However, the Col1a1CreSbdsExc progenies are embryonic lethal at E12-E15 stage due to developmental musculoskeletal abnormalities. Alternatively, we generated an inducible SDS mouse model by crossing Sbdsfl/flmice with Mx1Cre+ mice, and inducing Sbds deletion in Mx1-inducible BM hematopoietic and osteolineage niche cells by polyinosinic-polycytidilic acid (pIpC) administration. Compared with Sbdsfl/flcontrols, Mx1CreSbdsExc mice develop significantly decreased platelet counts, an inverted peripheral blood myeloid/lymphoid cell ratio, and reduced long-term HSC within BM, consistent with stress hematopoiesis seen in BMF and myelodysplastic syndromes. To assess whether inducible SBDS deficiency impacts niche function to engraft donor HSC, we transplanted GFP+ wildtype donor BM into pIpC-treated Mx1CreSbdsExc mice and Sbdsfl/flcontrols after 1100 cGy of total body irradiation (TBI). Following transplantation, Mx1CreSbdsExc recipient mice exhibit significantly higher mortality than controls (Figure 1). The decreased survival was related to primary graft failure, as Mx1CreSbdsExc mice exhibit persistent BM aplasia after HSCT and decreased GFP+ reconstitution in competitive secondary transplantation assays. We next sought to identify the molecular and cellular defects within BM niche cells that contribute to the engraftment deficits in SBDS-deficient mice. We performed RNA-seq analysis on the BM stromal cells from irradiated Mx1CreSbdsExc mice versus controls, and the results revealed that SBDS deficiency in BM niche cells caused disrupted gene expression within osteoclast differentiation, FcγR-mediated phagocytosis, and VEGF signaling pathways. Multiplex ELISA assays showed that the BM niche of irradiated Mx1CreSbdsExc mice expresses lower levels of CXCL12, P-selectin and IGF-1, along with higher levels of G-CSF, CCL3, osteopontin and CCL9 than controls. Together, these results suggest that poor donor HSC engraftment in SBDS-deficient mice is likely caused by alterations in niche-mediated donor HSC homing/retention, bone metabolism, host monocyte survival, signaling within IGF-1 and VEGF pathways, and an increased inflammatory state within BM niches. Moreover, flow cytometry analysis showed that compared to controls, the BM niche of irradiated Mx1CreSbdsExc mice contained far fewer megakaryocytes, a hematopoietic cell component of BM niches that we previously demonstrated to be critical in promoting osteoblastic niche expansion and donor HSC engraftment. Taken together, our data demonstrated that SBDS deficiency in BM niches results in reduced capacity to engraft donor HSC. We have identified multiple molecular and cellular defects in the SBDS-deficient niche contributing to this phenotype. Such niche signaling pathway-specific deficits implicate these pathways as critical for donor engraftment during HSCT, and suggest their potential role as targets of therapeutic approaches to enhance donor engraftment and improve HSCT outcome in any condition for which HSCT is required for cure. Disclosures Olson: Merck: Membership on an entity's Board of Directors or advisory committees; Bluebird Bio: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Miltenyi: Honoraria.

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 969-969
Author(s):  
Pietro Merli ◽  
Annalisa Ruggeri ◽  
Mattia Algeri ◽  
Giuseppina Li Pira ◽  
Giulia Ceglie ◽  
...  

β-thalassemia is one of the most common monogenic blood disorders worldwide, and is highly prevalent in Mediterranean countries. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has been the only curative treatment for transfusion-dependent β-thalassemia (TDT; the most severe disease form) for many years, but it is limited by donor availability and has a significant risk of morbidity and mortality. We conducted a chart review of patients with β-thalassemia who underwent allo-HSCT (N=80) at the Bambino Gesù Children's Hospital, Rome, Italy, between March 2011 and August 2018. Median (range) age at allo-HSCT was 5.5 (0.3-20.0) years [<12 years: n=70 (87.5%), ≥12-18 years: n=7 (8.8%), ≥18 years: n=3 (3.8%)] and all patients but one had TDT [n=79 (98.8%)]. Prior to allo-HSCT, patients received a median (range) of 17.4 (4-52) transfusions per year (n=64) and had a median (range) serum ferritin concentration of 1217 (135-9123) ng/mL and a median (interquartile range) hemoglobin level of 10.3 (9.3-11.4) g/dL. All patients had received regular iron chelation therapy prior to transplantation. In total, 18 (22.5%), 28 (35.0%), and 34 (42.5%) patients received allo-HSCT from human leukocyte antigen (HLA)-identical sibling donors, HLA-haploidentical donors, and unrelated donors (fully matched donor: n=28, donor with a single HLA disparity: n=6), respectively. Of these donors, 42 (52.5%) were carriers for thalassemia-associated mutations. In total, 53 (66.3%) donors and 35 (43.8%) recipients were cytomegalovirus-positive. Bone marrow was the stem cell source in 51 cases (63.8%), while 28 patients received an alphabeta T-cell depleted peripheral blood haploidentical HSCT (35.0%); the remaining child (1.3%) received both bone marrow and cord blood from the same related donor. All patients continued to receive transfusions immediately after allo-HSCT; however, only 7 (8.8%) received a transfusion in the 3 to 12-month post-transplantation period (2 due to underlying disease; 5 due to other reasons including GI bleeding). Median (range) time to reach transfusion-free status was 3.8 (1.1-47.8) weeks. Median (interquartile range) hemoglobin levels at 6 and 12 months after allo-HSCT were 10.9 (10.2-11.9) and 11.9 (10.6-13.0) g/dL, respectively. The cumulative incidences of primary and secondary graft failure were 10.0% and 12.5% at 24 months (HLA-identical donor: 0% and 11.1%, haploidentical donor: 17.9% and 3.6%, unrelated donor: 8.8% and 20.6%). Eleven out of 14 patients experiencing graft failure were successfully rescued with a second allograft, while 2 patients were not retransplanted due to parental decision and 1 patient died after the engraftment of the second allograft. Eight patients developed grade II-IV acute graft-versus-host disease (GVHD) and one patient developed moderate chronic GVHD. Cumulative incidence rates of grades II-IV and III-IV acute GVHD were 12.7% and 8.0% at 24 months (HLA-identical donor: 0% and 0%, haploidentical donor: 7.3% and 0%, unrelated donor: 23.8% and 18.8%). Three patients (3.8%) died of transplant-related causes (1 case each of hemophagocytic lymphohistiocytosis, sepsis, and multi-organ failure [the patient receiving the second allograft]) with a median (range) time from transplantation to death of 8.7 (3.7-11.0) months. Of these patients, all had been transplanted from an unrelated donor and 2 had reached sustained full-donor chimerism. The probability of overall and event-free (event defined as either death or primary/secondary graft failure) survival was 96.2% and 81.2% at 24 months (HLA-identical sibling donor: 100% and 88.9%, haploidentical donor: 100% and 78.6%, unrelated donor: 91.2% and 79.4%). The probability of thalassemia-free survival (event defined as either death or primary/secondary graft failure not rescued by a second allograft) was 93.7% at 24 months (HLA-identical sibling donor: 100%, haploidentical donor: 92.9%, unrelated donor: 91.2%). In this large single-center cohort of children with predominantly TDT, allo-HSCT led to beneficial outcomes for most patients, resulting in the discontinuation of transfusions with 93.7% of patients being thalassemia-free. Nevertheless, HSCT is still associated with GVHD, graft failure, and mortality, and only 22.5% of patients had an HLA-identical sibling donor, illustrating a key limitation of allo-HSCT. Emerging research is addressing such barriers to treatment. Disclosures Merli: Novartis: Honoraria; Sobi: Consultancy; Amgen: Honoraria; Bellicum: Consultancy. Algeri:Miltenyi: Honoraria; Atara Biotherapeutics: Consultancy, Honoraria; Bluebird bio: Consultancy, Honoraria. Gruppioni:Bluebird bio: Employment, Equity Ownership. Kommera:Bluebird bio: Employment, Equity Ownership. Maa:Bluebird bio: Employment, Equity Ownership. Locatelli:Bellicum: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; bluebird bio: Consultancy; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Miltenyi: Honoraria.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 10-10
Author(s):  
Rajni Agarwal ◽  
Kenneth I. Weinberg ◽  
Hye-Sook Kwon ◽  
Anne Le ◽  
Janel R Long-Boyle ◽  
...  

Successful hematopoietic stem cell transplantation (HSCT) requires vacating recipient hematopoietic stem cell (HSC) niches in the bone marrow to permit donor HSC engraftment that can provide life-long hematopoietic and immune function. Currently, HSCT in SCID relies on DNA damaging chemotherapy to eliminate recipient HSC and achieve niche clearance. We have pursued a non-toxic approach to target and deplete HSC using a humanized monoclonal antibody, JSP191, that binds human CD117 (c-Kit). We previously showed the safety and successful HSC engraftment in a Phase 1 trial of the first 6 patients with severe combined immunodeficiency (SCID), who underwent a second transplant because of HSC engraftment failure and poor immunity after their first transplantation. In these re-transplant patients even a low level of stringently measured myeloid chimerism resulted in significant and sustained generation of naive T cells and clinical improvement. Based on these results, the study of JSP191 (NCT#02963064)has opened a cohort of newly diagnosed infants with SCID. Here we report data from the first patient in this cohort, a SCIDX1 patient who received a primary HSCT with haploidentical CD34+ cells after conditioning with JSP 191. The patient had a c.270-15A>G variant in the IL2RG gene, which is predicted to cause a null phenotype. Besides a T- B+ NK- phenotype typical of SCIDX1 including dysfunctional B cells, the patient had anemia and intermittent neutropenia and thrombocytopenia. Despite evidence of maternal T cell engraftment, the patient had no clinical graft-versus-host disease (GVHD). The patient was initially enrolled in a trial of lentiviral gene therapy, but harvested bone marrow cells died in vitro during transduction and culture. The patient also mobilized poorly with G-CSF/Plerixafor. Further investigation revealed heterozygosity for loss-of-function mutations in two genes involved in DNA repair, BRCA1 and RAD51; Diepoxybutane (DEB) breakage study showed greater than normal pathologic chromosomal breaks, but less than that seen in Fanconi anemia. Because of concern for possible hypersensitivity to alkylating agent-based conditioning, the patient was referred for transplant with JSP191 conditioning. The patient received a CD34+ peripheral blood HSCT from his father after conditioning with 0.3 mg/kg of JSP 191 antibody intravenously over an hour on Day -8 and rATG (Thymoglobulin) on Day -5, -4, -3 and -2 (3.5 mg/kg total) to prevent rejection by the maternal T cells. The cryopreserved donor CD34+ cells were administered after sufficient clearance of the JSP191 serum level. The antibody infusion was well tolerated without toxicity, and the post-transplant course was uneventful without acute toxicities or GVHD. As a surrogate marker for HSC engraftment, CD15+ myeloid cells from peripheral blood were stringently sorted by flow cytometry and donor levels were quantified by short-tandem repeat (STR) analysis. Progressive levels of myeloid engraftment were observed beginning at Week 4. The level of donor chimerism at 12 weeks was 8% in the sorted CD15+ blood cells, and a marrow aspirate showed 25% donor CD34+ cells. By 3 months pre-existing abnormal CD19-CD20+ host B lymphocytes were significantly reduced, and CD19+ donor-derived B lymphocytes were emerging. At 2 months, CD4+ recent thymic emigrant and naïve T lymphocytes were observed, and by 3 months, overall T and NK lymphocyte numbers were 390/uL and 117/uL, respectively. Normal blastogenic responses to the T cell mitogen PHA were observed at 3 months. These first-in-class results provide proof of concept of the safety and efficacy of the use of JSP191 antibody to clear host marrow niche space to enable sufficient donor HSC engraftment and immune reconstitution as primary therapy of SCID. Non-genotoxic conditioning with JSP191 may replace conventional conditioning for newly diagnosed infants with SCID, thereby avoiding toxicities of chemotherapy. Disclosures Kohn: Allogene Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees; Orchard Therapeutics: Consultancy, Patents & Royalties, Research Funding. De Oliveira:Orchard Therapeutics: Research Funding; bluebird bio, Inc.: Research Funding. Czechowicz:Rocket Pharmaceuticals, Inc.: Research Funding. Brown:Merck: Membership on an entity's Board of Directors or advisory committees; Ansun: Membership on an entity's Board of Directors or advisory committees; Cidara: Membership on an entity's Board of Directors or advisory committees; Allogene: Membership on an entity's Board of Directors or advisory committees; Cellerant Therapeutics: Membership on an entity's Board of Directors or advisory committees. Shizuru:Jasper Therapeutics, Inc: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4363-4363
Author(s):  
Alexandre Janel ◽  
Nathalie Boiret-Dupré ◽  
Juliette Berger ◽  
Céline Bourgne ◽  
Richard Lemal ◽  
...  

Abstract Hematopoietic stem cell (HSC) function is critical in maintaining hematopoiesis continuously throughout the lifespan of an organism and any change in their ability to self-renew and/or to differentiate into blood cell lineages induces severe diseases. Postnatally, HSC are mainly located in bone marrow where their stem cell fate is regulated through a complex network of local influences, thought to be concentrated in the bone marrow (BM) niche. Despite more than 30 years of research, the precise location of the HSC niche in human BM remains unclear because most observations were obtained from mice models. BM harvesting collects macroscopic coherent tissue aggregates in a cell suspension variably diluted with blood. The qualitative interest of these tissue aggregates, termed hematons, was already reported (first by I. Blaszek's group (Blaszek et al., 1988, 1990) and by our group (Boiret et al., 2003)) yet they remain largely unknown. Should hematons really be seen as elementary BM units, they must accommodate hematopoietic niches and must be a complete ex vivo surrogate of BM tissue. In this study, we analyzed hematons as single tissue structures. Biological samples were collected from i) healthy donor bone marrow (n= 8); ii) either biological samples collected for routine analysis by selecting bone marrow with normal analysis results (n=5); or iii) from spongy bone collected from the femoral head during hip arthroplasty (n=4). After isolation of hematons, we worked at single level, we used immunohistochemistry techniques, scanning electronic microscopy, confocal microscopy, flow cytometry and cell culture. Each hematon constitutes a miniature BM structure organized in lobular form around the vascular tree. Hematons are organized structures, supported by a network of cells with numerous cytoplasmic expansions associated with an amorphous structure corresponding to the extracellular matrix. Most of the adipocytes are located on the periphery, and hematopoietic cells can be observed as retained within the mesenchymal network. Although there is a degree of inter-donor variability in the cellular contents of hematons (on average 73 +/- 10 x103 cells per hematon), we observed precursors of all cell lines in each structure. We detected a higher frequency of CD34+ cells than in filtered bone marrow, representing on average 3% and 1% respectively (p<0.01). Also, each hematon contains CFU-GM, BFU-E, CFU-Mk and CFU-F cells. Mesenchymal cells are located mainly on the periphery and seem to participate in supporting the structure. The majority of mesenchymal cells isolated from hematons (21/24) sustain in vitro hematopoiesis. Interestingly, more than 90% of the hematons studied contained LTC-ICs. Furthermore, when studied using confocal microscopy, a co-localization of CD34+ cells with STRO1+ mesenchymal cells was frequently observed (75% under 10 µm of the nearest STRO-1+ cell, association statistically highly significant; p <1.10-16). These results indicate the presence of one or several stem cell niches housing highly primitive progenitor cells. We are confirming these in vitro data with an in vivo xenotransplantation model. These structures represent the elementary functional units of adult hematopoietic tissue and are a particularly attractive model for studying homeostasis of the BM niche and the pathological changes occurring during disease. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1210-1210
Author(s):  
Elisabeth Bolton ◽  
Linda Kamp ◽  
Hardik Modi ◽  
Ravi Bhatia ◽  
Steffen Koschmieder ◽  
...  

Abstract Abstract 1210 Background: BCR-ABL1 transforms hematopoietic stem cells to induce chronic myeloid leukemia in chronic phase (CML-CP). Although CML is stem cell-derived, it is a progenitor cell-driven disease. In CML-CP, leukemia stem cells (LSCs) are characterized by elevated BCR-ABL1 expression in comparison to leukemia progenitor cells (LPCs). Increased expression of BCR-ABL1 kinase is also associated with progression from CML-CP to CML-blast phase. Previously we showed that BCR-ABL1 kinase stimulates reactive oxygen species (ROS)-dependent DNA damage resulting in genomic instability in vitro, which was responsible for acquired imatinib-resistance and accumulation of chromosomal aberrations (Nowicki et al., Blood, 2005; Koptyra et al., Blood, 2006; Koptyra et al., Leukemia, 2008). Result: To examine the effects of BCR-ABL1 expression on genomic instability during in vivo leukemogenesis we employed an inducible transgenic mouse model of CML-CP with targeted expression of p210BCR-ABL1 in hematopoietic stem and progenitor cells (Koschmieder et al., Blood, 2005). Mice exhibiting CML-CP-like disease resulting from BCR-ABL1 induction demonstrated splenomegaly, leukocytosis, and Gr1+/CD11b+ myeloid expansion in bone marrow, spleen and peripheral blood, as detected by FACS analysis. BCR-ABL1 mRNA expression was higher in Lin-c-Kit+Sca1+ stem-enriched cells than in Lin-c-Kit+Sca1- progenitor-enriched cells, thus reminiscent of CML-CP (LSCs>LPCs). BCR-ABL1 increased levels of ROS (hydrogen peroxide, hydroxyl radical) and oxidative DNA lesions (8-oxoG) in LSC-enriched Lin-c-Kit+Sca1+ cells. Preliminary data also suggested that quiescent (CFSEmax) Lin-c-Kit+Sca1+ cells from BCR-ABL1-induced mice exhibited greater ROS (superoxide) production than non-induced counter parts. Moreover, higher levels of ROS were detected in BCR-ABL1-positive Lin-c-Kit+Sca1+ stem-enriched population in comparison to BCR-ABL1-positive Lin-c-Kit+Sca1- progenitor population, suggesting a dosage-dependent effect of BCR-ABL1. To confirm that BCR-ABL1 exerts a dosage-dependent effect on ROS-induced oxidative DNA damage, we showed that the levels of ROS, 8-oxoG and DNA double-strand breaks were proportional to BCR-ABL1 kinase expression in murine 32Dc13 and human CD34+ cells. Conclusion: In summary, this mouse model recapitulates the BCR-ABL1 expression profile attributed to stem and progenitor populations in human CML-CP. It also shows that the BCR-ABL1-positive, stem cell-enriched Lin-c-Kit+Sca1+ population displays elevated levels of ROS and oxidative DNA damage in comparison to normal counterparts, which makes it suitable to study the mechanisms of genomic instability in LSCs. Single nucleotide polymorphism (SNP) arrays will shed more light on the genomic instability of this BCR-ABL1-induced transgenic model of CML-CP. Disclosures: Koschmieder: Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 962-962
Author(s):  
Bin Zhang ◽  
Yin Wei Ho ◽  
Tessa L. Holyoake ◽  
Claudia S Huettner ◽  
Ravi Bhatia

Abstract Abstract 962 Specialized bone marrow (BM) microenvironmental niches are essential for hematopoietic stem cell (HSC) lodgment and maintenance. However microenvironmental interactions of leukemia stem cells (LSC) are poorly understood. Although chronic myelogenous leukemia (CML) results from HSC transformation by the BCR-ABL gene, the role of the microenvironment in modulating leukemia development is not known. We employed the SCL-tTA-BCR/ABL mouse model of CML to investigate the LSC interactions with the BM microenvironment. In this model, targeted expression of the BCR-ABL gene in murine HSC via a tet-regulated SCL promoter results in development of a chronic phase CML-like disorder. We have reported that LSC capacity is restricted to BCR-ABL+ cells with long-term hematopoietic stem cell (LTHSC) phenotype(LSK Flt3-CD150+CD48-) (Blood 2010 116:1212A). LSC numbers are reduced in the BM but increased in the spleen of CML mice compared with LTHSC from control mice, suggesting that LSC have altered niche interactions. LSC also demonstrate altered trafficking with significant reduction in homing of IV injected LSC to BM, and markedly increased egress of intrafemorally injected LSC to the spleen, potentially related to reduced CXCL12 levels in the BM of CML mice. In addition, levels of several chemokines and cytokines, including MIP1α, MIP1β, MIP2, IL-1α, IL-1β, TNF-α, G-CSF and IL-6, were increased in CML BM, related to increased production by malignant hematopoietic cells. We investigated whether altered chemokine and cytokine expression was associated with altered capacity of the CML BM microenvironment to support LTHSC engraftment. LTHSC from control mice or LSC from CML mice were transplanted into irradiated CML or control recipients. There was reduced engraftment of both control LTHSC and CML LSC in the BM of CML compared to control recipients at 2 weeks after transplantation, associated with reduced homing to CML BM, potentially related to low BM CXCL12 levels. The numbers of control LTHSC in the BM of CML recipient mice remained low at 4 weeks post-transplantation, whereas the numbers of CML LSC increased to numbers similar to those seen in the BM of control recipients. Culture with CML BM supernatants (SN) resulted in impaired growth of control LTHSC compared to control BM SN. In contrast the growth of CML LSC was similar following culture with CML and control BM SN. Culture with individual factors at concentrations similar to those observed in CML BM (16ng/ml MIP1α, 8ng/ml MIP1β, 2.5ng/ml IL-1α, 3.5ng/ml IL-1β, 0.05ng/ml TNF-α) resulted in significantly reduced growth of normal LTHSC compared with CML LSC. These results indicate that diffusible factors produced by leukemic cells in the CML BM environment selectively inhibit normal LTHSC compared to CML LSC growth. Exposure of a murine stromal cell line to CML BM SN resulted in reduced CXCL12 mRNA levels compared to BM SN from control mice. The cytokine G-CSF, which was increased in CML BM SN, has been reported to reduce CXCL12 transcription. We observed significant reduction of CXCL12 mRNA levels in stromal cells cultured with G-CSF (0.2ng/ml), supporting a potential role for increased G-CSF production by leukemia cells in reduced CXCL12 production by CML BM stromal cells and reduced LSC retention in the BM. We evaluated whether defects in microenvironmental function in CML were affected by imatinib treatment. Treatment of CML mice with imatinib (200mg/kg/day, 2 weeks) led to reduction in MIP1α, MIP1β, IL-1β, and IL-6 levels in BM cells. Engraftment of normal LTHSC was significantly enhanced in BM of CML recipients pre-treated with imatinib. Results obtained with the mouse model were validated using specimens obtained from CML patients. CXCL12 mRNA levels were significantly reduced in human CML compared to normal MNCs, whereas expression of MIP1α, MIP-2, IL-1α and IL-1β were increased in CML MNCs, consistent with results obtained with the mouse model. Coculture with CML MNC conditioned medium (CM) resulted in selective impairment of growth of normal CD34+CD38- primitive progenitors compared to CM from normal MNC, but did not inhibit growth of CML progenitors. We conclude that leukemia-induced alterations in BM cytokine and chemokine levels contribute to altered LSC lodgment and to selective impairment of growth of normal LTHSC in the CML BM microenvironment, leading to a relative growth advantage for CML LSC over normal LTHSC and expansion of the leukemic clone. Disclosures: Holyoake: Novartis: Research Funding; Bristol Myers Squibb: Research Funding.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4558-4558
Author(s):  
Ibraheem Abosoudah ◽  
Asem Lashin ◽  
Fawwaz Yassin ◽  
Hassan Al trabolsi ◽  
Mohamed Bayoumy

Abstract Abstract 4558 Background: The aim of this study was to determine the outcome of pediatric allogeneic hematopoietic stem cell transplantation (Allo-HSCT) for nonmalignant disease in our center. Method: Data were retrospectively collected for all patients (aged 0–18 years) who received allogeneic HSCT between May, 2005 and December, 2011. Outcomes according to the type of transplant, diagnosis, and transplant-related complications are reported. Result: Allo-HSCT was performed in 17 patients, (11 male; 6 female). Bone marrow Failure (7;41%) was the commonest nonmalignant disease followed by B-thalassemia major (4;24%) and others (6;35%). Only HLA-matched family donors were used. Most patients were conditioned with Busulfan/Cyclophosphamide/ATG. GVHD prophylaxis comprised mainly of cyclosporine and methotrexate. The median time to neutrophil engraftment was 20 (9–27) days. Two patients experienced graft failure. Four patients had Grade (I–III) aGVHD and no patient had grade (IV). Four patients (23%) had chronic GVHD. No patient had sinusoidal obstruction syndrome (SOS). Five patients had reactivation of CMV infection, which was treated and resolved in all of them. Only one patient died of sepsis. Overall survival (OS) and event free survival (EFS) were 94%, and 88% respectively. Conclusion: In this cohort of patients, bone marrow failure was the main reason for transplantation. The early results of HSCT were promising and consistent with published international data. Similarly, graft failure remains a concern. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 5536-5536
Author(s):  
Yizel Elena Paz Nuñez ◽  
Beatriz Aguado Bueno ◽  
Isabel vicuña Andrés ◽  
Ángela Figuera Álvarez ◽  
Miriam González-Pardo ◽  
...  

Abstract Introduction The prognosis of patients with multiple myeloma (MM) has improved in the last years due to the important advances in the knowledge of the biology of the disease, the implementation of new drugs and the incorporation of autologous hematopoietic stem cell transplant (autoHSCT). The allogenic hematopoietic stem cell transplant (alloHSCT) continues to be controversial: it offers a curative potential but with the cost of high toxicity, limiting the procedure to those young patients with a high-risk disease. This procedure shall be performed in expert centers and, whenever possible, in the context of a clinical trial. In the following we describe the experience of our center with alloHSCT in advance multiple myeloma patients. Patients and methods A total of 18 patients were diagnosed with multiple myeloma received an alloHSCT during a 13 year period (1996-2013), with a median age of 46 ± 5.9 years. All of our patients received an allogenic HLA matched sibling donor with reduced-intensity conditioning. The majority of patients were transplanted because of advanced disease, relapse after an autologous transplant or as part of a sequential transplant in patient with a high risk disease. One patient received, in two occasions, an alloHSCT. Around 70% of patients had received more than 3 previous lines of treatment including, in nearly 95%, an autoHSCT. Patient's characteristics can be found on table 1, characteristics of the procedure can be found in table 2.Table 1.Patient«s CharacteristicsN (%)GenderMale Female10 (55,5%) 9 (44,4%)Secreted ProteinIgGκ IgG λ IgA κ BJ Plasmocitoma8 (44,4%) 4 (22,2%) 2 (11,1%) 3 (16,7%) 1 (5,6%)Debut DS stageII-A II-B III-A III-B Plasmocitoma5 (27,8%) 1 (5,6%) 8 (44,4%) 3 (16,7%) 1 (5,6%)Cytogentics at diagnosisMissing Unfavorable Favorable10 (55,5%) 6 (33,3%) 2 (11,1%)Previous lines of treatment²2 3-4 ³56 (33,3%) 10 (55,5%) 2 (11,1%)Previous autoHSCTYes No17 (94,5%) 1 (5,6%)Previous radiotherapyYes No8 (44,4%) 10 (55,6%)Disease status at transplantComplete remission Partial remission Relapse9 (50,0%) 3 (16,7%) 6 (33,3%)Table 2.Treatment characteristicsN (%)Conditioning regimenMyeloablative Reduced-intensity6 (33,3%) 12 (66.7%)Stem cell sourceBone marrow Peripheral blood4 (22.2%) 14 (77.8%)GVHD prophylaxisCsA+MTXCsA+CSCsA+MMF10 (55.6%) 3 (16.7%) 5 (27.8%)InfectionsYes No16 (88.9%) 2 (11.1%)MucositisYes No12 (66.7%) 6 (33.3%)Acute GVHDYes II-IV III-IV No4 (22.3%) 3 (16.7%) 1 (5.6%) 14 (77.8%)Chronic GVHDNo Limited Extensive8 (44.3%) 5 (27.8%) 5 (27.8%) Results: Transplant related mortality (TRM) before day 100th was one case due to a thromboembolic event. Global TRM was 16.6% (3 cases). The incidence of acute graft versus host disease (aGVHD) was 22%, controlled on most cases when corticosteroids were initiated. More than half of the patients developed chronic graft versus host disease (cGVHD), with an equal distribution on either presentation as limited or extensive. (Table 2) The total number of patients eligible for analysis was 17 (one patient was lost on follow-up). With a median follow up of 11 years, the overall survival (OS) was of 8.06 years [IC 95% 4,33-11,78] (figure 1.) and the estimated progression free survival (PFS) was of 25.83 months [IC 95% 8.87-42.79](figure 2). A total of 5 (29,4%) patients are still alive and 2 (11,7%) of them are in complete remission, of these 1 patient did not have a previous autoHSCT with a follow up of almost 15 years. Conclusions: Our results are similar to those reflected on the literature1-2. However we have to point out that our population is homogenous with advanced MM with more than 3 previous lines of treatment including in most cases auto-HSCT. In spite of this, morbility and mortality in our cohort was acceptable with the limitation of a high rate of cGVHD. There is a need of more studies including more patients to evaluate the role of alloHSCT in the era of new drugs for MM. References 1. Rosi-ol L et al. Allogeneic hematopoietic SCT in multiple myeloma: long-term results from a single institution. Bone Marrow Transplant. 2015. 2. Beaussant Y et al. Hematopoietic Stem Cell Transplantation in Multiple Myeloma: A Retrospective Study of the Société Française de Greffe de Moelle et de Thérapie Cellulaire (SFGM-TC). Biol Blood Marrow Transplant. 2015 Disclosures Alegre: Celgene Corporation: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 42-42 ◽  
Author(s):  
Stefan O. Ciurea ◽  
Ankur Varma ◽  
Piyanuch Kongtim ◽  
Samer Srour ◽  
Qaiser Bashir ◽  
...  

Introduction Allogeneic hematopoietic stem cell transplantation (AHSCT) is increasingly performed for older patients with AML; however, the optimal conditioning regimen for these patients remains unclear. Methods: We retrospectively evaluated outcomes of 404 patients with AML, ≥60 years receiving AHSCT at our institution between 01/2005-08/2018 who received 4 conditioning regimens: 1) fludarabine+melphalan 100mg/m2 (FM100, N=78), 2) fludarabine+melphalan 140mg/m2 (FM140, N=89), 3) fludarabine+IV busulfan x 4 days with Bu AUC≥5,000/day (equivalent dose 130mg/m2/day) (Bu≥5,000, N=131), 4) fludarabine+IV busulfan x 4 days with Bu AUC 4,000/day (equivalent dose 110mg/m2/day) (Bu4,000, N=106). To adjust for potential selection bias in choices of conditioning regimen, propensity score was calculated and used as a stratifying variable in a multivariable Cox regression model. Factors included in the propensity score calculation were age, secondary AML, ELN2017 genetic risk, remission status before transplant, induction failure, donor type, stem cell source and KPS. Results are presented for the FM100, FM140, Bu≥5,000 and Bu4000, respectively. Median follow-up survivors were 40, 74, 30 and 44 months, respectively (p=0.06). Donors are matched sibling, matched unrelated, haploidentical and mismatched unrelated donor in 126 (31%), 218 (54%), 40 (10%) and 20 (5%) patients, respectively. Patients in the FM100 group were significantly older and had lower KPS. The median age was 67, 64, 64 and 65 years, respectively (p=0.001), while 51%, 32%, 27% and 27% had KPS&lt;90%, respectively (p&lt;0.001). The HCT-CI of ≥3 was present in 57%, 62%, 56% and 70%, respectively (p=0.33), while 42%, 78%, 47% and 51% had high and very high-risk DRI, respectively (p&lt;0.001), and 12%, 46%, 18% and 32% of the patients were transplanted in active disease (p&lt;0.001). No significant differences were seen in both cytogenetic and ELN2017 genetic risk. More patients in FM100 group were treated using a standard of care protocol (73%, 64%, 25% and 31%, respectively, p&lt;0.001). Grade 2-4 aGVHD at day 100 were 26% vs. 26%, 36% and 40% (p=0.04), and extensive cGVHD at 3 years 14% vs. 42%, 36% and 37%, respectively (p=0.07). The NRM at 3 years were 19%, 29%, 25% and 21% (p=0.06), and 3-year relapse rates were 32% vs. 32%, 30% and 55%, respectively (p=0.003). Among 4 groups, FM100 group had a significantly better PFS and GRFS with 5-year PFS for these 4 groups were 44%, 30%, 33% and 22% (p=0.02) and 5-year GRFS were 28%, 20%, 18% and 9% (p=0.006), respectively (Figure 1). For subgroup of patients with KPS &lt;90%, 5-year PFS were 41%, 27%, 28%, 22%, respectively (p=0.007), while there was no significant difference between 4 conditioning groups in patients with high-risk AML defined as either secondary AML, induction failure or high-risk cytogenetics/high ELN2017 risk, suggesting that a more intense conditioning is not beneficial in this group of patients. The survival benefit of FM100 persisted after adjusted for baseline factors, transplant characteristics as well as propensity scores in a multivariable analysis (MVA). In MVA for PFS, HR was 0.57 (p=0.013) for FM100, 0.68 (p=0.056) for FM140 and 0.77 (p=0.137) for Bu&gt; 5000 as compared with Bu 4,000 group (Figure 1). In the MVA for GRFS, HR for FM100, FM140 and Bu&gt; 5000 was 0.53 (p=0.005), 0.78 (p=0.196), and 0.81 (p=0.178), respectively as compared with Bu 4,000 group. Other factors that independently predicted PFS were secondary AML (HR 1.68, p=0.001), remission status before transplant (HR 1.82, p=0.048 for CR with MRD positive, HR 1.87, p=0.043 for CR with unknown MRD status and HR 2.86, p=0.001 for active disease at transplant as compared with CR with MRD negative), KPS (HR 0.98, p=0.005) and use of a mismatched unrelated donor (HR 2.46, p=0.001 compared with matched related donor transplant). Conclusions: Older patients with AML benefit from a reduced-intensity conditioning with FM100 conditioning regimen, which was associated with better survival despite the fact that patients who could not receive more intense conditioning preferentially received this regimen. Higher intensity conditioning does not appear to improve survival in older patients. Alternative approaches to increase in conditioning intensity are needed to improve survival in patients with AML receiving allogeneic hematopoietic stem cell transplantation. Disclosures Ciurea: Kiadis Pharma: Membership on an entity's Board of Directors or advisory committees, Other: stock holder; Miltenyi: Research Funding; Spectrum: Membership on an entity's Board of Directors or advisory committees; MolMed: Membership on an entity's Board of Directors or advisory committees. Bashir:Imbrium: Membership on an entity's Board of Directors or advisory committees; Celgene: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Kite: Membership on an entity's Board of Directors or advisory committees; Acrotech: Research Funding; StemLine: Research Funding; Spectrum: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees. Oran:Astex pharmaceuticals: Research Funding; AROG pharmaceuticals: Research Funding. Popat:Bayer: Research Funding; Incyte: Research Funding; Jazz: Consultancy. Konopleva:Stemline Therapeutics: Consultancy, Honoraria, Research Funding; Reata Pharmaceuticals: Equity Ownership, Patents & Royalties; Ablynx: Research Funding; Astra Zeneca: Research Funding; Agios: Research Funding; Ascentage: Research Funding; Calithera: Research Funding; Forty-Seven: Consultancy, Honoraria; Kisoji: Consultancy, Honoraria; Eli Lilly: Research Funding; AbbVie: Consultancy, Honoraria, Research Funding; Cellectis: Research Funding; Amgen: Consultancy, Honoraria; F. Hoffman La-Roche: Consultancy, Honoraria, Research Funding; Genentech: Honoraria, Research Funding.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 32-33
Author(s):  
Christopher Nunes Gomes ◽  
Valerie Seegers ◽  
Aline Schmidt ◽  
Corentin Orvain ◽  
Alban Villate ◽  
...  

Introduction Citrulline, a non-essential amino acid produced exclusively by enterocytes in the small intestine and involved in the synthesis of L-arginine, is not metabolized by the liver. Therefore citrulline serum concentration is highly correlated with functional enterocyte mass, and decreases with digestive toxicity induced by conditioning therapy (radiotherapy and/or chemotherapy) for hematopoietic stem cell transplantation (HSCT) . Acute Graft-versus-host disease (GvHD), one of the major complications of HSCT, is correlated to conditioning-induced gut barrier damage and may be predicted by pre-transplant serum citrulline level (Rashidi, BBMT 2018). It could be interesting to know whether citrulline kinetics could also represent a biomarker for conditioning toxicity, non-relapse mortality (NRM), and GvHD. The aim of this study is thus to define group-based trajectory modeling, to identify clusters of individual serum citrulline kinetics in the early phase of allogeneic HCST, and to test whether these unsupervised trajectories were correlated with these early complications. Materials and Methods Serum citrulline was quantified by liquid chromatography in blood samples collected from consecutive patients who received an allogeneic HSCT in our institution between July 2014 and November 2019. These samples were drawn at different time-points: pre-transplant (D-7, D-3); day of transplant (D0), and post-transplant (D7, D15, D21). Distinct trajectories were identified for serum citrulline by using the semiparametric mixture model described by Nagin (Nagin, Stat Methods Med Res 2018). Results Among 161 patients (pts) included in the study, with a median age of 53 years (17-72), 98 pts (60.9%) received a reduced-intensity conditioning (RIC), 36 pts (22.4%) reduced-toxicity conditioning (RTC), 18 pts (11.1 %) sequential conditioning, and 9 pts (5.6%) myeloablative conditioning (MAC). Donor were identical sibling (22%), matched unrelated donor (52%) and haploidentical sibling (25%). Graft source was peripheral blood mononuclear cells in 144 pts (89.4%) and bone marrow in 17 pts (10.6%) respectively. HCT-CI score was low, intermediate and high-risk in 38%, 32%, and 30% of pts respectively. Disease-Risk Index (DRI) was low/intermediate in 111 pts (69%) and high/very-high in 50 pts (31%). With a median follow up of 29.1 month, 3-year overall survival (OS), disease-free survival (DFS), and NRM rates were 64.5%, 58.3%, and 18.9%, respectively. The median number of citrulline samples per patient was 7 [3-16]. Median citrulline concentrations before conditioning and at D-3, D0, D7 and D15 were statistically different during RIC, RTC, MAC, and sequential conditioning (p&lt;0,001 respectively) but was not different at D21 (p=0.296). In the whole cohort, 3 citrulline trajectories were determined in an unsupervised method. Patients belonging to these 3 trajectories were different according to intensity of conditioning received with lower citrulline trajectories during MAC and sequential conditioning (p&lt;0.001). In the uper citrulline trajectorie, pts were significantly older (p=0.005). However, citrulline trajectories were not correlated to OS (p = 0.1), NRM (p=0.24), cumulative incidence of acute GvHD (p=0.39) or chronic GvHD (p=0.2). After restricting the analysis to pts who received RIC conditioning (n=98), higher pre-HSCT citrulline concentrations were associated with a lower NRM (p=0.042). Unsupervised analysis in this setting individualized 4 clusters of individual trajectories (figure 1), that did neither distinguish age (p=0.28), DRI (p=0.87), HCT-CI score (p=0.81) nor the incidence of acute (p=0.6) or chronic (p=0.4) GvHD. However, the lowest citrulline trajectory contained significantly more haploidentical transplantations (p=0.004) and less pts who received antithymocyte globulin for GvHD prophylaxis (p=0.005). Interestingly in this RIC cohort, cumulative incidence of NRM at 12 months was 23%, 21%, 8%, and 0% respectively according to the 4 citrulline trajectories (figure 2). Conclusion In patients receiving allogeneic HSCT, the variation of serum citrulline concentrations depends on the intensity of the conditioning regimen. In patients who received RIC conditioning, lower plasma citrulline trajectories are associated with higher NRM. In this setting, citrulline may be an attractive biomarker for predicting conditioning toxicity and NRM. Disclosures Hunault: Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Diachi: Membership on an entity's Board of Directors or advisory committees; Jansen: Honoraria; Servier: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees. Thepot:astellas: Honoraria; novartis: Honoraria; sanofi: Honoraria; celgene: Honoraria.


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