bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mesenchymal Stem Cell As a Salvage Treatment For Refractory Acute Graft-Versus-Host Disease: a Matched Pair Analysis
Authors: Zhao Ke , Lou Rui , Huang Fen , Peng Yanwen , Jiang Zujun , Huang Ke , Zhang Yu , Fan Zhiping , Zhou Hongsheng , Liu Can , Xiao Yang , Sun Jing , Xiang Peng , Liu Qifa 
Published: October 2019

Abstract

Background
Refractory acute graft versus host disease (aGVHD) is a major cause of death after allogenetic haematopoietic stem cell transplantation (allo-HSCT). This study evaluated the efficacy and safety of mesenchymal stem cells (MSCs) from bone marrow of a third-party donor to refractory aGVHD.

Methods
Twenty-five patients with refractory aGVHD were enrolled in this prospective study. MSCs were given at a median dose of 1×106 cells/kg once weekly until aGVHD got complete response (CR) or MSCs were infused for a total of 8 doses. In order to evaluate infections, tumor relapse and cGVHD, 25 refractory aGVHD patients with MSCs treatment was matched with grade II-IV aGVHD patient without MSCs in the corresponding period

Results
After a total of 112 doses of MSCs were administered, with a median of 4 (range:2-12) doses per patient, the overall response (OR) rate for aGVHD was 72%,including CR in 56% and partial response (PR) in 16%. The efficacy of MSCs to aGVHD was significantly related with the severity and the number of involved organs of aGVHD, but unrelated with the onset timing of MSC. The incidence of CMV and EBV infections, including viremia and associated disease, was not different between MSCs and non-MSCs groups during aGVHD treatment and follow-up. At a median follow-up time of 126 (range: 49–1067) days post-transplantation, only two patients relapsed in MSCs group, compared with four relapsed in the control group. Tumor relapse was not different between the two groups (P=0.771). No toxic side effects and other secondary tumors were observed after MSCs treatment except for one EBV-associated post-transplant lymphoproliferative disorders (PTLD). The incidence of cGVHD in MSCs group, especially extensive cGVHD, was lower than that in non-MSCs group (25.0% Vs 68%, P=0.001; 20.0% Vs 64%, P=0.043, respectively). The ratio of CD3+CD4+/CD3+CD8+ T cells and the proportion of CD4+CD25+ regulatory T cells (Tregs) at 8 weeks after MSCs were higher than that before treatment (P=0.037 and P=0.020, respectively), and there were not different from the healthy people at 36 weeks after treatment.

Conclusions
MSCs derived from bone marrow of third-party donors are effective to refractory aGVHD. It might not increase the risks of infections, tumor relapse, but reduce the incidence and severity of cGVHD.

Disclosures:
Liu: Science and Technology Program of Guangzhou of China (11A72121174): Research Funding; National Natural Science Foundation of China (Grant No.81000231, No.81270647): Research Funding; National Public Health Grand Research Foundation (Grant No. 201202017): Research Funding; 863 Program (No. 2011AA020105): Research Funding.
Pre-Transplant Weight Loss and Total Serum Protein Predict Relapse Of Acute Myeloid Leukaemia After Allogeneic Stem Cell Transplantation
Authors: Luft Thomas , Dietrich Sascha , Radujkovic Aleksandar , Stölzel Friedrich , Falk Christine , Benner Axel , Schaich Markus , Bornhäuser Martin , Ehninger Gerhard , Kraemer Alwin , Hegenbart Ute , Ho Anthony D , Dreger Peter 
Published: October 2019

Abstract

Background
Although allogeneic stem cell transplantation (alloSCT) represents a curative chance for higher risk acute myeloid leukaemia (AML), relapse occurs in a significant proportion of patients. The impact of nutritional status on the outcome of allogeneic stem cell transplantation (alloSCT) is controversial. This study investigates the influence of pre-transplant body mass index (BMI), weight loss, and serological indicators of nutritional homeostasis on relapse and death of acute myeloid leukemia (AML) after alloSCT.

Methods
Pre-transplant weight loss and BMI along with serum levels of total serum protein (TSP), albumin, C-reactive protein, and leptin were collected retrospectively in a training cohort of 149 patients allografted for AML and correlated with clinical outcome. A metabolic risk score was established and tested in an independent validation cohort (n=167).

Results
Pre-transplant weight loss exceeding 2%, TSP lower than 70 g/L, and decreased leptin levels were associated with a significantly increased risk of relapse and death. In contrast, we did not observe a consistent pattern for the impact of nutritional indicators on non-relapse mortality (NRM). Multivariate analyses adjusting for age, cytogenetic risk, treatment line, blast count at alloSCT, donor, and conditioning confirmed weight loss and low TSP as independent risk factors of relapse and overall survival, but not of NRM. Weight loss >2% and low TSP were used to build a metabolic score for prediction of relapse risk and mortality. In multivariate analyses with clinical confounders, patients with both metabolic risk factors had a strongly increased risk of relapse (p=0.0003, HR 15.62, 95%CI 3.51-69.71) and death (p=0.002, HR 3.64, 95%CI 1.62-8.18) compared to patients without metabolic risk factor. The risk prediction of the metabolic score could be confirmed in the validation cohort (Figure 1).

Conclusions
Altered nutritional homeostasis prior to alloSCT predicts the risk of recurrence of AML after transplantation. Studies addressing pretransplant nutritional interventions in order to reduce AML relapse rates are warranted.

Disclosures:
No relevant conflicts of interest to declare.
Autologous Transplantation Is Safe and Effective For Patients With Multiple Myeloma Related Renal Insufficiency
Authors: Greene Claire C , Hwang Jimmy , Lee Wolf Jeffrey , Damon Lloyd E , Mahindra Anuj , Martin Thomas G 
Published: October 2019

Abstract

Introduction
Patients (pts) with MM often present with varying degrees of renal insufficiency (RI) which can cause significant morbidity. In younger pts with MM, high-dose chemotherapy with autologous stem cell transplantation (ASCT) has been shown to enhance remission and possibly improve survival. In pts with RI there has been concern about the safety and efficacy of proceeding to ASCT. At our center, ASCT has been routinely offered to pts with RI. Herein we report the results of MM pts with RI who received ASCT since 2000.

Patients and Methods
Outcomes of 50 MM pts with RI were compared to 100 matched ASCT recipients. The matched transplant pts studied were similar with respect to subject-, disease-, and transplant-related characteristics. All pts met standard eligibility criteria for ASCT and pts with RI had a serum creatinine (Cr) level of >2 mg/dL (average Cr = 6.07 with a range of 2 to 11.79 mg/dL), at the time of ASCT. 14 of the 50 pts were on dialysis at the time of ASCT. All patients had active MM requiring therapy and all pts had evidence of stable disease or treatment response prior to transplant. For pts with RI, the average age at transplant was 56 years (range 33 to 69 yrs) and the median time between diagnosis and ASCT was 302 days. The preparative therapy consisted of single agent Melphalan, given on Day (-3) or (-2) with a median administered dose of 140 mg/m2 (range 100-200 mg/m2) while the dose for the matched patients was 200mg/m2. All pts were hospitalized for ASCT and received standard supportive care; >2 x 10e6/Kg CD34(+) cells, G-CSF, transfusions as necessary and appropriate anti-infectives.

Results
The 30-day and 100-day treatment related mortality (TRM) rates for both the patients with RI and matches were 0%. Amongst the patients with RI, 4 patients required ICU care and the average duration of hospitalization was 23.36 days (range: 14 - 48 days) and duration of hospitalization for matches 19.4 days (range: 11-58 days). Time to ANC > 0.5 x10e9/L was 12 days (range 10-21 days) and 12 days (range 10-22 days) in the RI and matched cohort respectively. Time to platelets > 20 x 10e9/L was 11 days (range: 6-22 days) and 14 days (range 8-51days) in the RI and matched cohort respectively. 32% of pts with RI were in very good partial response (VGPR)+ complete remission (CR) of which 12% were in CR at ASCT. After ASCT, 50% of pts achieved a VGPR+CR of which 34% pts achieved a CR. The mean overall survival (OS) for patients with RI was 4.2 yrs and for controls was 6.5 yrs [Figure 1. HR 2.036, 95% CI (1.204-3.443) p=0.0084].

Conclusion
ASCT is a safe and effective treatment option for MM pts with RI including those on dialysis with engraftment characteristics similar to pts without RI.

Disclosures:
Wolf: Onyx: Honoraria; Millenium: Honoraria; Celgene: Honoraria, Research Funding.
Ligand-Regulated and Developmental Stage-Specific Expression Of The EPO Receptor During Human Erythroid Progenitor Cell Formation
Authors: Rainville Nicole , Kuhrt David , Su Su , Jachimowicz Edward , Ruth Asch , Li Lei , Green Jennifer M , Wojchowski Don M. 
Published: October 2019

Abstract
Upon engagement of its cell surface receptor, EPO sharply regulates erythroid progenitor cell (EPC) development. Little is known concerning the dynamics of EPOR expression, however, due to its rarity in primary cells. Using EPO dosing and response studies together with a highly specific and sensitive hEPOR antibody, we provide new insight into stage and ligand dose-dependent regulation of cell surface EPOR expression among human bone marrow derived primary EPCs. Developmentally, EPOR levels peaked within a KITposCD36posGPAneg proerythroblast cohort. In contrast to prior studies using transfected murine myeloid cell lines, the limiting of EPO substantially increased EPOR levels, demonstrating ligand dependent modulation of endogenous EPOR in hEPCs. EPO dosing and withdrawal studies further showed that in early EPCs EPO efficiently supported survival but not proliferation. In GPApos erythroblasts EPOR levels were diminished, but GPApos cells nonetheless exhibited strong EPO dependency for both survival and growth. Investigations provide novel insight into regulated EPOR surface expression among developing primary EPCs, and may also aid in understanding the action modes and effects of emerging EPOR agonists and erythropoiesis stimulating agents.

Disclosures:
No relevant conflicts of interest to declare.
Cathelicidin Mediates Anti Lymphoma Cytotoxicity By Human Macrophages
Authors: Bruns Heiko , Fabri Mario , Büttner Maike , Mougiakakos Dimitrios , Pasemann Shirin , Amann Kerstin , Mackensen Andreas , Gerbitz Armin 
Published: October 2019

Abstract
In high-grade lymphatic malignancies, such as Burkitt’s lymphoma (BL), macrophage infiltration represents a characteristic morphological hallmark. Although macrophages can be directly cytotoxic against tumor cells, tumor associated macrophages (TAMs) regularly fail to kill them. The mechanism responsible for this loss of function remains unknown. Here, we firstly demonstrate that M1 (classically activated) macrophages selectively kill proliferating lymphoma cells by releasing the antimicrobial peptide cathelicidin in a vitamin D dependent fashion. Moreover, we show that cathelicidin leads to cell death by targeting the mitochondria. In contrast, M2 (alternatively activated) macrophages, and M2-like TAMs in BL exhibit an altered vitamin D metabolism that leads to reduced production of cathelicidin and consequently failure to lyse lymphoma cells. However, treating M2 macrophages with 1,25D or a vitamin D receptor agonist efficiently triggers cathelicidin-mediated tumoricidal activity against BL cells. Taken together, these observations indicate that a therapeutic activation of the vitamin D pathway could restore antitumor activity of TAMs, which are an important player in the tumor stroma.

Disclosures:
Mackensen: Eli Lilly: Consultancy.
Tyrosine Phosphatase SHP-1 Acts As a Key Regulator Of Alloresponses In Primary Murine T Cells
Authors: Kardinal Christian , Herbst Jessica , Diekmann Ulf , Sauer Martin G. 
Published: October 2019

Abstract

Background
T cell-mediated alloresponses may result in severe transplantation-related morbidity and mortality such as graft rejection or graft versus host disease. After the adhesive interaction of a T cell and an allogeneic antigen-presenting cell an integrin-mediated, detrimental response against tissues expressing the respective alloantigen is being initiated. So far, the molecular processes underlying signaling events between T cell receptor activation and cellular adhesion are not fully understood. The vast majority of published studies was done with various tumor-derived cell lines, thus producing controversial results depending on the cell line used.

Methods
To overcome these drawbacks, we used in vitro generated polyclonal primary T cells based on the priming of naïve T cells from B10.A mice (responder) with denditic cells from C57BL/6 mice (allogeneic stimulator) or from B10.A mice (syngeneic stimulator) to study the lymphocyte function-associated antigen 1 (LFA-1)-mediated adhesion.

Results
We identified the protein tyrosine phosphatase SHP-1 as a key regulator of LFA-1-mediated adhesion. Upon alloactivation of primary T cells LFA-1-mediated adhesion was significantly higher when compared to syngeneically stimulated cells. Furthermore, elevated adhesion of alloactivated cells was accompanied by a strong decline of SHP–1 activity. To reinforce these findings, we examined the influence of a siRNA-based knockdown of SHP-1 from syngeneically and allogeneically stimulated T cells. Most notably, transfection of syngeneically stimulated cells with SHP-1-specific siRNA resulted in a two-fold increase of adhesion, when compared to cells transfected with nonsense siRNA under identical conditions. In contrast, transient overexpression of wild–type SHP-1 in allostimulated cells strongly reduced LFA–1-mediated adhesion.
Since our experiments have ascertained SHP–1 as a negative regulator of the adhesion-associated signaling cascade SLP-76 → ADAP → LFA–1, we investigated the tyrosine phosphorylation of ADAP. Western blots revealed strong tyrosine phosphorylation of ADAP in allogeneically stimulated cells, but not in syngeneically stimulated cells. Furthermore, SHP-1 binding with ADAP was significantly stronger in syngeneically stimulated cells, when compared to allogeneically stimulated cells. Besides these experiments, substrate specificity of SHP–1 to ADAP confirmed by in vitro dephosphorylation asssays with GST-SHP–1 and GST-SHP–2 fusion proteins indicate that SHP–1 modulates the binding of SLP–76 with ADAP by tyrosine dephosphorylation of ADAP.

Conclusion
These findings might be of clinical relevance, since the decisive role of SHP–1 in the regulation of LFA–1-mediated adhesion in alloresponses allows the development of novel target-specific immunosuppressive agents.

Disclosures:
No relevant conflicts of interest to declare.
Development Of Mature T Lymphocytes Requires Alpha-Synuclein
Authors: Shameli Afshin , Xiao Wenbin , Harding Clifford , Meyerson Howard , Sumodi John , Maitta Robert 
Published: October 2019

Abstract

Synucleins (including α-, β- and γ-synucleins) are a group of proteins that are expressed at high levels in the central nervous system. The physiologic function of these proteins is unknown. Alpha-synuclein has been implicated in the pathogenesis of neurodegenerative disorders such as Parkinson's disease and Lewy body dementia, as it is highly expressed in the Lewy bodies from both disorders. The expression of α-synuclein in hematopoietic system has been shown in erythroid precursors and megakaryocytes in bone marrow, as well as erythrocytes and platelets in peripheral blood. Moreover, some studies demonstrated the expression of α-synuclein on peripheral blood mononuclear cells (PBMC), including B and T lymphocytes, NK cells and monocytes; and its expression is shown to be higher in PBMCs of individuals with Parkinson's disease compared to healthy controls.
In order to study the role of α-synuclein in development of different hematopoietic elements, we compared bone marrow, peripheral blood and lymphoid organs of age and sex-matched α-synuclein knock-out (KO) mice and wild type (WT) animals of the same genetic background (n=10). Flow cytometric analysis of bone marrow elements did not show differences in the percentages and absolute numbers of erythroid, megakryocytic and myeloid lineages (data not shown). However, differential complete blood cell count (CBC) showed statistically significant decrease in red blood cell (RBC) count, hemoglobin (Hb) and hematocrit (Hct) in KO mice compared to WT mice. No difference was noted in other RBC indices (Table 1). However, platelets were smaller in KO mice as measured by the mean platelet volume (MPV). There was no difference in the number of platelets and white blood cell (WBC) counts. There was a significant reduction in the percentage of circulating lymphocytes, and associated increase in the percentage of neutrophils and monocytes in KO mice compared to WT mice, although the difference in the number of lymphocytes did not reach statistical significance (Table 1).
Flow cytometric analysis of T lymphocytes in thymus and peripheral lymphoid organs demonstrated marked defect in development of mature T cells. There was a significant increase in the number of double negative thymocytes in KO mice associated with significant decrease in the number of single positive T cells. Furthermore, splenic CD4+ and CD8+ T cells were markedly decreased in KO mice, indicating that α-synuclein is required for T cell development (Table 2).
In summary, our findings indicate an absolute requirement for α-synuclein in development of mature T lymphocytes. The underlying mechanism for this function is subject of future studies. Moreover, while α-synuclein-deficiency does not affect the development of myeloid lineage and platelets, lack of this protein is associated with lower number of erythrocytes, suggesting its role in development and/or survival red blood cells.

Disclosures:
No relevant conflicts of interest to declare.
Engineering The Human Thymic Microenvironment To Support Thymopoiesis
Authors: Montel-Hagen Amelie , Chung Brile , Ge Shundi , Blumberg Garrett , Klein Sam , Yuhua Zhu , Parekh Chintan , Arumugam Balamurugan , Yang Otto , Crooks Gay M. 
Published: October 2019

Abstract
A system that allows manipulation of the human thymic microenvironment is needed both to elucidate the extrinsic mechanisms that control human thymopoiesis, and to develop potential cell therapies for thymic insufficiency. Implantation of intact fetal thymic fragments into immune deficient mice can be used to model human thymopoiesis in vivo, but this approach has limited capacity for cell or molecular manipulation for either experimental or translational application. We developed an implantable thymic microenvironment composed of two human thymic stroma populations critical for thymopoiesis, thymic epithelial cells (TECs) and thymic mesenchyme (TM). TECs and TM from postnatal human thymi were cultured in specific conditions, allowing cell expansion and manipulation of gene expression, prior to re-aggregation into a functional thymic unit. Human CD34+ hematopoietic stem and progenitor cells (HSPC) differentiated into T cells in the aggregates in vitro and in vivo following inguinal implantation of aggregates in immune deficient mice. Cord blood HSPC previously engrafted into murine bone marrow, were able to migrate to the implants and differentiate into functional human T cells with a broad T cell receptor repertoire. Furthermore, lentiviral mediated expression of vascular endothelial growth factor in TM enhanced TEC survival and function, resulting in significantly greater thymocyte production relative to control implants. These results demonstrate an efficient in vivo system for the generation of T cells from human HSPC, and represent the first model to allow manipulation of gene expression and cell composition in the microenvironment of the human thymus.

Disclosures:
No relevant conflicts of interest to declare.
Malleable Extracellular Domains In Platelet GPIb-IX Complex
Authors: Zhou Liang , Yang Wenjun , Li Renhao 
Published: October 2019

Abstract

Background
Glycoprotein (GP)Ib-IX complex is critical to hemostasis and thrombosis. Its proper assembly is closely correlated with its surface expression level and requires cooperative interactions among extracellular and transmembrane domains of GPIbα, GPIbβ, and GPIX subunits. Two interfaces have been identified between 2 GPIbβ and GPIX extracellular domains.

Objective
To understand how extracellular domains interact in GPIb-IX.

Methods
The GPIbβ extracellular domain (GPIbβE) or the GPIX counterpart (GPIXE) in GPIb-IX was replaced simultaneously or individually with a GPIbβE/GPIXE chimera called GPIbβEabc (Fig1), and the effect of domain replacement on assembly and expression of the receptor complex in transiently transfected Chinese hamster ovary cells was analyzed.

Results
Five chimeric complexes, along with wild-type complex shown in Fig1, are characterized. All five chimeric complexes formed wild-type-like GPIbα-GPIbβ disulfide bonds, indicating that the interactions between extracellular domains do not affect formation of the GPIbα-GPIbβ disulfide bonds. Replacing GPIXE with GPIbβEabc in GPIb-IX retained interface 1, but not interface 2. While this domain replacement retained the ability of GPIbβ to aid expression of GPIX and the overall complex organization, the reciprocal enhancing effect of GPIX on expression of GPIbβ and GPIbα was lost. However, when the extracellular domain in GPIbβ was replaced with GPIbβEabc, surface expression level of each subunit in chimeric complex 3 and chimeric complex 4 expressing cells, was slightly lower than those in wild-type complex expressing cells, but significantly higher than those in other chimeric complexes expressing cells, indicating that chimeric complexes 3 and 4 share the same stability, but adopt different conformations. After replacing the ectodomains in both GPIbβ and GPIX with GPIbβEabc, the expression levels of GPIbα and associated subunits in chimeric complex 5 expressing cells were as low as those in chimeric complex 1 expressing cells, despite the different ability of GPIbβEabc and GPIbβE to self-associate.

Conclusions
The results demonstrate the importance of the association between GPIbβ and GPIX extracellular domains for assembly and efficient expression of GPIb-IX. In particular, interface 2 is critical for the stability of GPIbβ in the complex. However, not all the effects of extracellular domain replacement on GPIb-IX expression can be explained by the two separate interfaces, suggesting that GPIbβ and GPIX extracellular domains are malleable to accommodate and propagate potential conformational changes therein. This finding has significant implication on the molecular mechanism underlying the GPIb-IX-mediated signaling in platelets.

Disclosures:
No relevant conflicts of interest to declare.