bluuebunny/crossref_metadata_2025_split huggingface dataset:
Branched Polyethylenimine-Superparamagnetic Iron Oxide Nanoparticles (bPEI-SPIONs) Improve Immunogenicity of Myeloma Tumor Antigen to Enhance Th1 Polarization of Dendritic Cells
Authors: Hoang My-Dung , Lee Hwa-Jeong , Lee Hyun-Ju , Jung Sung-Hoon , Choi Nu-Ri , Vo Manh-Cuong , Nguyen-Pham Thanh-Nhan , Park In-Kyu , Kim Hyeoung-Joon , Lee Je-Jung 
Published: October 2019

Abstract
Introduction: The application of nanoparticles in dendritic cell (DC)-based cancer immunotherapy represents a promising strategy to enhance antigen-specific T cell immune responses. This study was to investigate the effect of bPEI-SPIONs on antigen-specific T cell responses elicited by DCs loaded with apoptotic U266 myeloma tumor antigen in the presence or absence of bPEI-SPIONs.
Materials and Methods: The myeloma tumor antigens were prepared as following: 1) apoptotic U266 cells by UBV-irradiation and overnight incubation (16 h irradiated cells) and 2) apoptotic U266 cells by UVB-irradiation and 2 h incubation in the absence (2 h irradiated cells) or 3) presence of bPEI-SPIONs (bPEI-SPION 2 h irradiated cells). Monocyte-derived immature DCs were activated with TNF-α, loaded with several kinds of myeloma tumor antigens 2 h after TNF-α stimulation, and cultured for 2 days.
Results: Optimal concentration of bPEI-SPIONs was 16 µg/mL to uptake into tumor cells and the bPEI-SPIONs render U266 cells sensitive to UVB-irradiation through reactive oxygen species (ROS) induction pathway hence accelerated the apoptotic cell death. 2 h irradiated cells and bPEI-SPION 2 h irradiated cells released immunogenic proteins, including HSP70, HSP90, and HMGB1. bPEI-SPION 2 h irradiated cells were easily up-taken by DCs without alteration of surface phenotypes and migration capacities. DCs loaded with bPEI-SPION 2 h irradiated cells showed highest IL-12p70 production level and Th1 polarization compared to other DCs.
Conclusion: These results suggest that bPEI-SPIONs are a promising tool to improve immunogenicity of myeloma tumor cells and to enhance Th1 polarization of DCs loaded with these tumor cells.

Disclosures
No relevant conflicts of interest to declare.
Targeting on the Stem Cell Niche Can Protect Hematopoietic Stem Cell from Chemotherapy and G-CSF
Authors: Li Sidan , Zhai Qiongli , Zou Dehui , Li Changhong , Qiu Lugui 
Published: October 2019

Abstract
The majority of hematopoietic stem/progenitor cells (HSPCs) reside in the bone marrow surrounded by specialized bone-shielded environment. The specialized microenvironment or niche not only provides a favorable habitat for HSPC maintenance and development but also governs stem cell function.
Here we investigated the potential role of bone remodeling osteoblasts and osteoclasts in homeostasis and stress-induced mobilization of hematopoietic progenitors, then further tested the hypothesis that targeting the niche might improve stem cell–based therapies using six mouse models to mimic the multiple rounds of chemotherapy followed by autologous hematopoietic stem cells (HSCs) transplantation in a clinical setting.
Herein, we show that multiple rounds treatment of cytotoxic drugs influence niche. Serum osteocalcin level declined obviously (22.19 ± 1.08 ng/mL, before treatment vs 16.08 ± 2.12 ng/mL, steady state, P=0.01) in autologous HSPCs transplant patients. In mouse models, the number of CD45- Ter119- OPN+ osteoblast was significantly reduced (untreated, 3993 ± 129 cells/femur; CTLs, 1937 ±196 cells/femur; Gs, 1055 ± 43 cells/femur; P<0.01). Pharmacologic use of parathyroid hormone (PTH) or receptor activator of nuclear factor kappa-B ligand (RANKL) increases the number of HSC mobilized into the peripheral blood for stem cell harvests and protects stem cells from repeated exposure to cytotoxic chemotherapy. Ttreatment with granulocyte colony stimulating factor (G-CSF) plus PTH led to relative preservation of the HSC pool (G vs PTH, P<0.01; CTL vs PTH, P<0.05). Recipient mice transplanted with circulation HSPCs of P+R and P+R+G groups also showed more robust myeloid and lymphatic cell engraftment than did HSCs from either CTL or G group.
These data provide evidence that targeting the HSPC niche may improve the efficacy of HSPC mobilization.

Disclosures
No relevant conflicts of interest to declare.
­Impact of Porcine-Human Mixed Hematopoietic Chimerism on Human NK Cell Response to Porcine Cells
Authors: Vishwasrao Paresh , Markus Holzl , Li HaoWei , Choi Goda , Megan Sykes 
Published: October 2019

Abstract
Mixed hematopoietic chimerism permits durable tolerance of T, B and NK cells to xenoantigens in a rat to mouse bone marrow transplant model. However, it is unclear whether tolerance of human NK cells to pig xenoantigens can be induced by mixed hematopoietic chimerism. We assessed the tolerance of human NK cells towards pig cells in a humanized mouse model with established pig and human mixed xenogeneic chimerism. Pig and human mixed chimeras (MCs) were generated by injection of pig bone marrow cells to irradiated pig cytokine (IL3, GMCSF and SCF) transgenic NOD-scid common gamma chain knockout (NSG) mice followed by injection of human fetal liver CD34+ cells 3 day later. In the control group, only human CD34+ cells were transplanted. 12 weeks post-transplant, hydrodynamic injection of plasmid encoding human Flt3L followed by injection of three rounds of recombinant IL15/IL-15 receptor alpha Fc complex was given to promote human NK cell reconstitution. The control non–mixed chimeric group (Non-MC) received the same treatment without pig cells. 12 days following induction of human NK cell reconstitution, human NK cells from both MC and Non-MC mice were isolated from the spleen and their cytotoxic responses in vitro to pig cells were determined in a chromium release assay. In addition, the presence of pig cells in various tissues of the chimeric mice was studied.
While human NK cells were usually undetectable in peripheral blood prior to the injection of human Flt3L plasmid and IL-15/IL-15 receptor alpha-Fc complex, they were detected by 5 days post-injection of IL-15 protein. 12 days post-induction of human NK cell reconstitution, pig cells remained detectable in peripheral blood, spleen, bone marrow and liver in the chimeric mice together with human NK cells. The co-existence of human NK cells and pig cells suggested that human NK cells in MCs might be tolerant to pig cells. Consistent with this notion, cytotoxicity assays showed that human NK cells from MCs demonstrated decreased killing of pig PBMC blasts compared to NK cells from Non-MC mice. Importantly, killing of K562 cells by NK cells from MCs mice was also decreased compared to that of Non-MC mice, suggesting that human NK cell tolerance to pig cells induced by mixed chimerism was associated with global hyporesponsiveness, as we have previously observed in a rat-to-mouse bone marrow transplantation model. Moreover, higher percentages of CD56highCD16low and lower percentages of CD56lowCD16high human NK cell subsets were observed in bone marrow of chimeric mice than in non-chimeric mice, indicating that the development of human NK cells in bone marrow might be altered by the presence of pig cells. In summary, our data suggest that mixed xenogeneic chimerism may induce tolerance of human NK cells towards porcine cells, but the tolerance may be associated with global hyporesponsiveness.

Disclosures
No relevant conflicts of interest to declare.
Thymus Transplantation Plus Allogeneic Bone Marrow Transplantation Can Induce Strong Graft-Versus Leukemia Effects with Low Risk of Graft-Versus-Host Disease
Authors: Zhang Yuming , Feng Xiaoqing , Wu Cuiling , Guo Wenling , Li Huiping , Yuan Shanshan 
Published: October 2019

Abstract
Abstract: [Objective] Allogeneic bone marrow transplantation (allo-BMT) has been used for the treatment of refractory leukemia and donor lymphocyte infusion (DLI) was used for the purpose of graft versus leukemia (GVL) effects. However, DLI is associated with a risk of graft versus host disease (GVHD). Thus, new cellular-based methods are desired. In the present study, we performed thymus transplantation (TT) plus allo-BMT to explore it’s anti leukemia effects. [Methods] Recipient B6 mice (H-2b) bearing leukemia (EL-4 cells, H-2b) were irradiated 8 Gy. The next day, bone marrow cells from BALB/c mice (H-2d) were transplanted into the B6 mice. Simultaneously, DLI and thymus transplantation from the same donor were carried out. The survival period of the recipient B6 mice were examined, histological studies were performed in the liver, intestine, and the engrafted thymus from the recipients 4 weeks after the BMT. Surface markers on lymphocytes from the spleen were analyzed by 3-color fluorescence staining using a FACScan system to determine chimerism. [Results]. All mice treated with BMT showed fully donor-derived chimerism(H-2d). The survival rate in mice treated with BMT plus TT was significantly prolonged compared with those treated with BMT alone or BMT plus DLI. Histologically, both the cortex and medullar areas of the engrafted thymus under the renal capsule were clearly shown. Normal T-cell differentiation was also observed in the engrafted thymus. Microscopic founding of small intestine and liver in the BMT plus TT group indicated mild GVHD, whereas those treated with BMT plus DLI showed moderated to serious GVHD. The number of the CD4+ cells was significantly greater in the mice treated with BMT+TT compared with those with BMT alone or those with BMT + DLI. The percentage of FoxP3+ regulatory T cells among CD4+ cells was higher in the mice treated with BMT + TT comparable to those treated with BMT + DLI. The results for CD8+ T cells were similar to those for CD4+ cells. [Conclusion]. Allo-BMT combined with TT induces high thymopoiesis, and can elicit strong GVL effects with mild GVHD reaction. We thus found that donor-derived T cells play an important role in the treatment of leukemia. Also the details of the mechanisms are still unknown, one possibilities may be the continuous supplementation of T cells from the allogeneic thymus. The results of the present study suggest this strategy will become a new way for the treatment of refractory or relapse leukemia in human.

Disclosures
No relevant conflicts of interest to declare.
Acute Graft Versus Host Disease after Donor Lymphocyte Infusion: A Single Center Analysis
Authors: He Fiona C. , Weisdorf Daniel J. , Warlick Erica D. , Miller Jeffrey S. , Holtan Shernan G. , Verneris Michael R. , Cao Qing , MacMillan Margaret L. 
Published: October 2019

Abstract
Donor lymphocyte infusion (DLI) is an option for relapsed hematologic malignancies following allogeneic hematopoietic cell transplantation (HCT). We analyzed the incidence and manifestations of acute graft versus host disease (GVHD) in patients with malignant and non-malignant conditions treated with DLI. At the University of Minnesota, we gave 171 DLI to 120 patients from 1995-2013. The cumulative incidence of grade II-IV acute GVHD was 31.6% (CI 25-42%,n = 40); grade III-IV 23.3% (CI 16-32%,n = 29). GVHD after DLI (n = 46) included involvement of skin in 70% (n = 32), lower gastrointestinal (GI) 65% (n = 30), upper GI 43% (n = 20), and liver 35% (n = 16). Patients receiving chemotherapy prior to DLI (chemo-DLI) had more frequent acute GVHD and GI GVHD. Significant risk factors for grade II-IV acute GVHD included: age > 40, chemo-DLI, malignant disease, and time from HCT to DLI < 200 days. Response to treatment of acute GVHD at 8 weeks was complete in 40% and complete/partial in 52%.
Patients developing GVHD had frequent disease response. In chronic myelogenous leukemia (CML) patients, responses were excellent (80%) with or without GVHD. The CR rate was 34% for non-CML malignancies; only 9% achieved CR without acute GVHD. Non-malignant diseases showed poor prognosis following acute GVHD and good prognosis without. Overall survival at 2 years for CML patients was similar (83% vs 79%, p = 0.89) with or without grade II-IV acute GVHD, but in non-CML malignancies survival was better in absence of acute GVHD (41% vs 22%, p = 0.04).
We observed frequent, yet therapy-responsive acute GVHD following DLI. DLI often induced remission in CML, but less so for non-CML malignancies without chemo-DLI, particularly in absence of acute GVHD. Improvements in DLI efficacy and GVHD management are still needed.

Disclosures
No relevant conflicts of interest to declare.
CD40L+ CD8+ T-Cell Dependent Antitumor Immunity
Authors: Thiel Andreas , Frentsch Marco , Listopad Joanna , Stark Regina , Sada Japp Alberto , Matzmohr Nadine , Meier Sarah , Taniuchi Ichiro , Blankenstein Thomas 
Published: October 2019

Abstract
CD40 is frequently expressed on malignant cells of different origin. Due to the observed antitumorigenic effects induced after CD40 engagement it represents an attractive target for immunotherapies. We demonstrate here that CD40L expressing tumor-specific CD8+ T-cell population can act as potent physiological CD40 agonist against CD40 expressing tumor cells. We demonstrate that in the course of cancer cell rejection high frequencies of tumor-specific CD40L+ CD8+ T cells are induced. Strikingly, in contrast to wild-type (wt), CD40L deficient CD8+ T cells were unable to prevent tumor formation in lymphopenic as well as in fully immunocompetent hosts. Apparently, in our setting CD40L expressed by CD8+ T cells is essential for cancer cell rejection. CD40L-mediated rejection does not depend on interaction with CD40+ host cells such as antigen-presenting cells but on CD40 expression by cancer cells. Our findings disclose CD40L expression by CD8+ T cells as a new antitumor effector function that should be implemented in future adoptive T-cell therapies against cancer.

Disclosures
No relevant conflicts of interest to declare.
Cytopenia at Diagnosis Impairs Stem Cell Mobilization Among Patients with Multiple Myeloma
Authors: Toprak Selami Kocak , Uslu Atilla , Atilla Erden , Topcuoglu Pervin , Gurman Gunhan , Ilhan Osman , Beksac Meral 
Published: October 2019

Abstract
Introduction:
The GIMEMA group has recently developed a risk score predicting mobilization failure (Musto et al, EHA 2014). The risk score included age, cytopenia at diagnosis, induction therapy and their toxicity. In this study we aimed to evaluate the impact of these factors on peripheral blood stem cell (PBSC) mobilization among patients with multiple myeloma (MM).
Patients and methods:
125 newly diagnosed patients with MM (M: 76, F: 49) planned for autologous stem cell transplantation; median age 58 years (range, 30-67) were included in the analysis. This retrospective study examined the impact of age (> 60 years), gender of the patients, cytopenia (Hb<10 gr/dL, absolute neutrophil count < 1x109/L, thrombocyte count < 100x109/L) at diagnosis, and severe hematological toxicity during induction therapy, the type of induction and mobilization methods, the presence of neuropathy, comorbid diseases such as diabetes mellitus, hypertension and renal failure (creatinine > 2 mg/dL), and the use of beta blocker drugs. Patients with CD34+ levels of <20/μL in peripheral blood at maximum stimulation were considered to be Poor Mobilizers. The total amount of PBSC <5x106/kg after a single mobilization procedure was defined as sub-optimal collection. Poor mobilization was observed in only two patients (<2x106/kg). Statistics: Comparison of categorical variables was evaluated by chi-square test or Fisher exact test. Nominal variables were compared with non-parametrical test, Mann-Whitney U or Kruskal Wallis test. P value below as 0.05 was accepted as significance.
Results:
Optimal mobilization with median two apheresis (1-4) sessions for PBSC was obtained in 85.6% of the patients (n=107). Median CD34+ cells in this group were 8.33x106/kg (5-27x106/kg). The presence of cytopenia at diagnosis was the only significantly detrimental factor on mobilization (90% vs 77.1%, p=0.04). When the patients was scored in four groups as having single or combined variables (age, cytopenia at the diagnosis or during induction therapy), we were not able to develop a risk score.
Conclusions:
In our experience, 14.4% of the myeloma patients showed suboptimal or poor mobilization. Use of bortezomib, age, presence of neurotoxicity or hematological toxicity at mobilization did not significantly impair mobilization. We were able to confirm only cytopenia at diagnosis, from the four factors reported by Musto et al, as a detrimental factor impairing the stem cell mobilization.

Disclosures
No relevant conflicts of interest to declare.
The Cell Loss after Thawing in Cord Blood Units
Authors: Karasu Gulsun , Uygun Vedat , Kilic Suar Caki , Ozturk Zeynep , Dincer Zeynep , Yesilipek M. Akif 
Published: October 2019

Abstract
Umbilical cord blood (CB) are increasingly used for allogeneic transplantation as an alternative source to bone marrow or peripheral stem cell for patients who lack a human leucocyte antigen (HLA)-matched donor. Cell dose is one of the main determinant factor for selection of the unit and it has been shown to correlate with time and probability of engraftment. Cell doses available for selection of the unit are the ones evaluated before cryopreservation. Processing of the graft either with cryopreservation and/or thawing inevitably lead to cell loss but the data showing to what extent is very limited although this has great importance especially for the units with critical cell counts. To evaluate the extent of the cell loss after thawing and the effect of preservation duration on cell loss and the viability, we retrospectively analyzed our single center experience in a cohort of patients receivingunrelated CBT.
Sixty cord blood units used for unrelated CBT in fifty-eight patients in our Pediatric Stem Cell Transplantation Unit were included in the study. One of the patient was transplanted with double cord blood unit and one had recurrent CBT because of previous graft failure.
Median number of declared TNC per kilogram of recipient body weight was 16x107/kg (range: 3,16-59,1). After thawing the median TNC dose decreased to 11,1x107/kg (range:1,5-34), with median cell viability at 80%. The median TNC recovery was found as 70%. Median CD 34+ cell count declared by the banks per kilogram body weight of recipient was 6,0x105/kg (range: 0,5-37). The CD 34 cell count of one of the units used in a patient having double cord blood infusion was not available. The CD34 cell count of the other complementary unit was 0,48x105/kg. Since the total cell counts received bu the recipient was given, the CD34 cell count of the patient having double CB infusion was not included in statistical analysis. The median postthawed CD 34 cell count was 3,4 x105/kg (range: 0-21)and median CD34 cell recovery was %58.
The storage duration of the CB units in liquid nitrogen was available for 59 units and that was 52±30 months (range:3-130 months). Correlation analysis did not show any significant correlation between CB unit storage duration and viability (r=-0,2 p=0.07). Also any correlation between storage time and also TNC and CD34 cell recovery were not identified.
Our study indicated that approximately 30% of cell loss is expectable in cord blood transplantation because of either cryopreservation or thawing. It should be kept in mind while assessing acceptibility of cord blood units with limited cell counts

Disclosures
No relevant conflicts of interest to declare.
Recombinant scAAV2 Vector-Mediated Ex Vivo Transduction of Primary Human Hematopoietic Stem Cells from a β-Thalassemia Patient and Human β-Globin Gene Expression in a Murine Xenograft Model in Vivo
Authors: Song Liu-Jiang , Zhang Xin-Hua , Zhu Jun , Wu Jue-Lian , Yin Xiao-Ling , Tan Meng-Qun 
Published: October 2019

Abstract
Background: The most severe form of β-thalassemia, β°-thalassemia major, is characterized by the complete absence of normal β-globin chain, and is often lethal. Autologous transplantation of genetically-modified hematopoietic stem cells (HSCs) using lentiviral vectors have been used successfully to achieve clinical efficacy in one patient, although clonal expansion of a myeloid cell population also occurred in this patient which was associated with the activation of a cellular proto-oncogene, HMGA2. We reasoned that recombinant vectors based on a non-pathogenic human parvovirus, the adeno-associated virus (AAV), might offer a safer alternative. We have previously documented that although the conventional single-stranded (ss) AAV2 vectors mediated β-globin gene transfer and expression in primary human fetal liver cells and in human HSCs from patients with β-thalassemia patients in vitro, the level of transgene expression was sub-optimal. In the present study, we investigated whether double-stranded self-complementary (sc) AAV2 vectors could overcome this limitation.
Methods: Human HSCs, obtained from a β-thalassemia homozygous patient, were mock-transduced or transduced with recombinant scAAV2-β-globin vectors at 5×104 vgs/cell, followed by i.v. injection into sub-lethally irradiated NOD/SCID mice (2.65 cGy total body irradiation), which were also pre-treated with 200 µg purified anti-IL2RB/CD122 monoclonal antibody. Recipient mice were sacrificed 12 weeks post-transplantation. Bone marrow cells from recipient mice were analyzed by BFU-E assays. Human β-globin gene expression in human erythroid progenitor cells from transplanted mice was evaluated by RT-PCR.
Results: Pre-treatment of NOD/SCID mice with anti-CD122 antibody improves engraftment of human HSCs in bone marrow of receipt mice. Human β-actin (538-bp) and β-globin (272-bp) transcripts were detected by RT-PCR in bone marrow cells from all recipient mice, indicating that recombinant scAAV2-β-globin–transduced HSCs from a patient with β-thalassemia were successfully transduced and transplanted in these mice and that human β-globin gene was transcriptionally active 12 weeks post-transplantation.
Conclusion: Our results indicate that human HSCs from β-thalassemia patients can be efficiently transduced by recombinant scAAV2-β-globin vectors followed by expression of normal human β-globin gene. These studies provide the proof-of-concept that scAAV2 vector-mediated gene transfer into human HSCs might be a potentially safer alternative approach for gene therapy of β-thalassemia.

Disclosures
No relevant conflicts of interest to declare.