julilili42/papers huggingface dataset:
Visual acuity changes in cone and cone‐rod dystrophies
2011-11-18

Citation information: Prokofyeva E, Troeger E, Bernd A &amp; Zrenner E. Visual acuity changes in cone and cone‐rod dystrophies. Ophthalmic Physiol Opt 2011. doi: 10.1111/j.1475‐1313.2011.00883.x Abstract Purpose: The purpose of the study was to evaluate longitudinal visual acuity (VA) changes in cone (CD) and cone‐rod dystrophies (CRD) in order to develop recommendations for follow‐up strategies and to define an optimal time for potential therapeutic intervention. Methods: Patients with clinically defined CD and CRD, who had at least three clinical examinations within a follow‐up period of a minimum of 2 years, were included in the study. The observation period was divided into segments: between 1–2 visits and 2–3 visits in intervals of 2 years, and between 3–4 visits in 3‐year intervals. Disease history was collected during the baseline examination. Median age of onset, age at first examination, and period between disease onset and 1st visit (latency) were estimated. Medians with 25th and 75th quantile of VA decrease in logMAR for each segment of observation were calculated. The median percentage of VA decrease was also calculated. Results: Initial results of the Tuebingen longitudinal study of VA changes in CRD and CD are presented as medians with 25th and 75th quintiles. Twenty‐nine patients (14 men and 15 women) were studied. Nineteen of them had CRD and 10 CD. Median age at the baseline visit was 18 (11, 31) years for CRD and 26 (8, 41.5) years for CD. Median age of disease onset was 9 (8, 25) years for CRD and 7.5 (5, 15) years for CD. The median latency was 6.5 (3; 8.25) years in CD and 4 (2, 10) years in CRD patients. VA in CD and CRD patients was significantly different only during the first visit ( p &lt; 0.03). VA decrease was highest in the period between 2–3 visits with a median VA decrease of 36%, for CDR and between 3–4 visits for CD with a median VA decrease of 80%. In the CRD group the rate of VA decline was fairly even over the four visits, whereas in the CD group the decline appeared to progressively increase towards the end of the follow‐up. Conclusion: CRD patients were younger than those with CD at a baseline visit and had a longer period of follow‐up. A statistically significant difference in VA in CRD and CD was observed at the first ophthalmological examination only. VA decrease was most prominent in the second decade of life in CRD and in third decade in CD patients. CRD was characterized by a more progressive VA decrease than CD. CRD had a high decline of VA over the second and the third examination, whereas VA decline in CD progressed towards the end of follow‐up period (fourth examination). These results should be considered when advising and following up such patients on a long‐term basis.
Clofarabine Containing Conditioning Regimen for Allo-SCT in AML/ALL Patients: A Survey From the Acute Leukemia Working Party of EBMT
2011-11-18

Abstract Abstract 3004FN2 Clofarabine (CLO), a second generation purine analogue, has demonstrated an efficient anti-leukemia activity while showing a favorable toxicity profile. The aim of our study was to analyse the results of CLO as part of the conditioning regimen prior to allo-SCT for the treatment of patients with AML or ALL. This retrospective multicenter report assessed the outcome of 90 patients who received a clofarabine-containing conditioning regimen allogeneic stem cell transplantation (allo-SCT) for AML (n=69) or ALL (n=21) between November 2006 and September 2010 and reported on the EBMT registry. The median age was 42 years (range: 18–69) at transplant. The majority of patients presented with an active disease at transplant (CR1 n=8; CR2 n=16, active disease n=66). All patients had received a CLO-containing conditioning regimen (RIC n=88; MAC n=2) with the following combinations: CLO/TBI n=27; CLO/Busulfan n=10; CLO/Busulfan/ATG n=32; CLO/others drugs n=21. With a median follow-up of 14 months (range: 1–45), 2-years OS, LFS, relapse incidence, non-relapse mortality (NRM) and chronic GVHD were 28+-5%, 23+-5%, 41+-6%, 35+-5% and 38+-7%, respectively. When comparing AML and ALL patients, OS and LFS were significantly higher for AML patients (OS: 35+-6% vs 0%, p&lt;0.0001); LFS: 30+-6% vs 0%, p&lt;0.0001). Overall, engraftment was achieved in 84% of patients with no difference between AML and ALL patients. Patients achieving CR from an active disease were 66.5% in AML vs 40% in ALL (p=0.06). Also, 2-year chronic GVHD was 35% in AML vs 17% in ALL, p=0.32. In a Cox multivariate analysis, AML was the only factor associated with a better LFS (HR=0.37; 95%CI: 0.21–0.66, P=0.001). We conclude that the use of CLO-containing conditioning regimen for allo-SCT is an effective treatment for high-risk AML patients as CLO seems to provide higher anti-tumor and alloreactivity effects. In high-risk ALL patients, disappointing results are observed. Prospective studies are needed to evaluate the potential role of CLO as part of reduced toxicity conditioning regimens in acute leukemias. Disclosures: No relevant conflicts of interest to declare.
Expression and Immunomodulatory Function of RANKL in Leukemia
2011-11-18

Abstract Abstract 245 The TNF family member RANKL and its receptors RANK and osteoprotegerin (OPG) are key regulators of bone remodelling, but have also been shown to influence progression of malignancies like breast cancer (Tan et al., Nature 2011), myeloma (Sordillo et al., Cancer 2003) and CLL (Secchiero et al. J Cell Physiol. 2006). NK cells are cytotoxic lymphocytes that play an important role in tumor immune surveillance especially of hematopoietic malignancies. Their reactivity is influenced by a variety of activating and inhibitory molecules expressed by their target cells including several members of the TNF family. Recently, we reported that RANK, upon interaction with RANKL which can be expressed by malignant hematopoietic cells, mediates signals that impair NK reactivity (Schmiedel et al., Blood 2010 116,21:893–893). Here we extended these analyses and comprehensively studied the expression and immunomodulatory function of RANKL in leukemia. Analysis of primary leukemia cells revealed substantial RANKL surface expression in a high proportion of the investigated cases (AML, 47 of 65 (72%); ALL, 16 of 21 (76%); CML, 6 of 10 (60%); CLL, all 54 (100%)). Signaling via surface-expressed RANKL into the malignant cells mediated the release of cytokines like TNF, IL-6, IL-8 and IL-10 which have been shown to act as autocrine and paracrine growth and survival factors in leukemia. Moreover, the factors released upon RANKL signaling upregulated RANK expression on NK cells. In line, NK cells from leukemia patients (n=75) displayed significantly (p&lt;0.001, Mann-Whitney U-test) higher RANK expression compared to healthy controls (n=30) confirming our notion that RANK-RANKL interaction may contribute to leukemia pathophysiology. We further found that RANK-RANKL interaction, beyond directly inhibiting NK cell function via RANK, may contribute to evasion of leukemia cells from NK immunosurveillance by creating an NK inhibitory cytokine milieu. This was revealed by impaired cytotoxicity and degranulation in response to leukemia targets following exposure of the NK cells to the factors released upon RANKL signaling by leukemia cells. Notably, the RANKL-mediated cytokine release of leukemia cells could be disrupted by the clinically approved RANKL antibody Denosumab/AMG162. Thus, RANKL signaling may trigger a “vicious cycle” comprising of release of immunosuppressive cytokines and also upregulation of RANK on NK cells. The latter both directly inhibits NK reactivity and may result in augmented RANKL signaling into leukemia cells. Our data suggest that therapeutic modulation of the RANK/RANKL system e.g. with Denosumab/AMG162, which is approved for treatment of osteolysis, may be a promising strategy to reinforce NK reactivity against hematopoietic malignancies. Disclosures: No relevant conflicts of interest to declare.
No apparent accretion mode changes detected in Centaurus X-3
2011-11-18

\\n Aims. Two distinct spectral states have previously been reported for Cen X-3 on the basis of RXTE/ASM observations. Intrigued by this result, we investigated the spectral properties of the source using the enhanced possibilities of the X-ray data now available with the aim to clarify and interpret the reported behavior.\\n Methods. To check the reported results, we used the same data set and followed the same analysis procedures as in the work that reported the two spectral states. Additionally, we repeated the analysis using the enlarged data sample including the newest RXTE/ASM observations as well as the data from the MAXI monitor and from the INTEGRAL/JEM-X and ISGRI instruments.\\n Results. We were unable to confirm the reported presence of the two spectral states in Cen X-3 either in the RXTE/ASM data or in the MAXI or INTEGRAL data. Our analysis shows that the flux variations in different energy bands are consistent with a spectral hardness that is constant over the entire time covered by observations.\\n
Commensal Bacteria Are Dispensable in Neutropenia-Induced G-CSF Regulation
2011-11-18

Abstract Abstract 4830 Introduction: G-CSF is generally accepted to be the major cytokine regulating neutrophil production, but neutrophil steady-state homeostasis has still not been fully elucidated. We have previously shown in NODSCIDcγ−/− mice that feedback G-CSF expression upon antibody-based neutrophil depletion occurs independent from lymphocytes (Bugl et al., ASH 2010) and hypothesized that there may be a sensing mechanism of neutropenia relying on the presence of microbial components, similar to emergency granulopoiesis. Therefore, germ-free wildtype mice received anti-neutrophil antibodies and underwent further analysis. Moreover, passive regulation of circulating G-CSF levels by neutrophil cell mass was examined. Methods: Anti-Ly6-G antibody (clone 1A8) was used to induce neutropenia in germ-free C57BL/6 mice. After one week of neutrophil depletion hematopoietic tissues and peripheral blood were harvested and analyzed on cellular, protein and RNA level. Moreover, neutrophil granulocytes (granulocyte-differentiation antigen-1+ Mac-1+) purified from peripheral blood of C57BL/6 mice were transfused into neutropenic wild type mice and plasma G-CSF was monitored. Results: Peripheral blood neutropenia could be effectively induced in all experimental mice by anti-1A8 antibody. Transfusion of 3.5 × 106 neutrophils into neutropenic wild type mice did not significantly change plasma G-CSF levels. Filgrastim (rhG-CSF), however, caused significant downregulation of bone marrow G-CSF at the mRNA level. Germ-free C57BL/6 mice were analyzed after 1 week of antibody-induced neutropenia and showed a shift of myeloid progenitors towards granulocyte macrophage precursors (GMP) at the expense of megakaryocyte erythrocyte progenitors (MEP) as well as significantly increased numbers of hematopoietic stem cells. In addition, G-CSF, M-CSF, and CXCL12 behaved identically in both germ-free control and wild type mice under specific-pathogen free conditions. Conclusions: Transfusion of G-CSF-receptor (CSF3R) positive neutrophils did not significantly influence G-CSF. Moreover, exogenous G-CSF downregulated marrow G-CSF on the transcriptional level. Germ-free mice are able to mount a feedback loop including G-CSF upregulation and marrow changes in progenitor cell distribution analogous to mice carrying physiological commensal bacteria. Our data are therefore consistent with G-CSF feedback regulation occurring independent from commensal germs. Moreover, our data indicate transcriptional rather than CSF3R+ cell mass-associated passive regulation of G-CSF levels. Taken together, we propose a model of myeloid bone marrow homeostasis, where feedback loops of neutrophil production upon antibody-dependent neutropenia occur through transcriptional upregulation of G-CSF. The underlying mechanisms occur independent of lymphocytes and presence of germs. Disclosures: No relevant conflicts of interest to declare.
Inhibition of Antibody Production in Vitro with Bispecific CD20 X CD95 Antibodies
2011-11-18

Abstract Abstract 1114 Antibodies directed against the B-cell associated CD20 surface antigen can target normal as well as malignant B cells. They are sucessfully used for the treatment of B-cell derived leukemia and lymphoma and antibody mediated autoimmune disease, respectively. We have previously described that bispecific antibodies with specificity for CD20 and the death receptor CD95 are capable of inducing CD95 mediated apoptosis selectively in CD20-positive lymphoma cells. We now show that CD20 X CD95 hybrid antibodies induce apoptosis in pokeweed mitogen (PWM) activated B cells expressing CD95, but not in resting cells lacking it. Antibody production induced by PWM in vitro is profoundly inhibited. These results indicate that bispecific CD20 X CD95 antibodies may be used for the treatment of antibody mediated autoimmune disease. Compared to monospecific CD20 antibodies these reagents offer a new effector principle and specificity for activated rather than resting B cells. Disclosures: No relevant conflicts of interest to declare.
Clinical Grade Generation of T-Helper-1-Driven Polyclonal T-Cell Populations for Adoptive Immunotherapy Against Tumor Associated Antigens
2011-11-18

Abstract Abstract 4314 Adoptive T cell therapy has been shown an option to treat patients with malignancies. In contrast to vaccinations, T cells for adoptive T-cell therapy are generated ex vivo to be re-infused into the recipient. This enables treatment of immunocompromized hosts and use of allogeneic T cells to exploit graft versus tumor effects. Adoptive T-cell therapy involving CD4+ T-helper cells (Th cells), intends to induce sustained T-cell responses in vivo. The Th1 cytokine interferon-gamma (IFN-γ) has not only an effect in orchestrating cytotoxic T-cell reponses, IFN-γ by itself has antitumor effects. Transferring T cells in a lymphopenic host furthermore eliminates regulatory T cells (Tregs) and offers access to homeostatic cytokines. The aim of our study was the translation of preclinical data into a GMP conform clinical scale protocol to generate specific T cells for adoptive T-cell therapy against tumor associated antigens. Large scale generations of NY-ESO-1 specific T cells was performed according to current GMP regulations in a GMP facility. In brief, peripheral blood mononuclear cells from healthy donors were primed with an overlapping NY-ESO-1 15-mer peptide mix. The priming was done in the presence of IL-7 and IL-2. T cells were enriched using IFN-γ capture technique and expanded for two weeks in autologous culture conditions with IL-7, IL-15 and IL-2. T-cell specificity, function and proliferation capacity was analyzed by flow cytometry. The T-cell products showed high numbers of specifically IFN-γ+, TNF-alpha+ T cells. Tolerance inducing cytokines like IL-10 were absent. Enrichment of Tregs was excluded. Both, CD4+ and CD8+ T cells with an effector memory phenotype proliferated in response to NY-ESO-1. CD107a assays demonstrated cytotoxic capacities of T cells. The T-cell product did not include alloreactive T cells. In summary GMP-conform generation of NY-ESO-1 specific T cells was established. Although tumor associated antigens are potential self antigens, it is possible to induce a functional Th1 response in peripheral blood T cells from healthy donors. Adoptive T-cell therapy against tumor associated antigens could have implications for multiple tumor entities in autologous as well as allogeneic treatment approaches. Disclosures: No relevant conflicts of interest to declare.
Neutropenia Does Not Delay Lymphopoietic Regeneration in NODSCIDcγ−/− Mice
2011-11-18

Abstract Abstract 4831 Introduction: Previously it was demonstrated that lymphopoiesis is rapidly established after transplantation of wild type stem cells into lymphopenic NODSCIDcγ−/− mice. These data were interpreted as evidence for an “empty” preformed lymphopoietic niche being replenished by lymphoid progenitors. We hypothesized that antibody-induced neutropenia might influence early post transplant fate decision to myeloid rather than lymphoid differentiation resulting in delayed lymphoid reconstitution. Materials and Methods: 25,000 flow sorted CD45.2-expressing wild type Lin-/Sca1+/c-Kit+ (LSK) cells from C57BL/6 mice were transplanted into sublethally irradiated B-/T-/NK-cell deficient NODSCIDcγ−/− mice (CD45.1). Three groups of n = 7 mice received anti-Gr1 or anti-1A8 i.p. every 48 h to induce continuous antibody-mediated neutropenia vs. PBS as control. Blood was harvested at regular intervals to monitor the engraftment. After 16, 22, and 34 days, animals were sacrificed and underwent blood and bone marrow analysis. Results: Hematopoietic regeneration started with the emergence of donor-derived monocytes in all groups as well as neutrophils in the control group as early as 9 days after transplantation. On day 14, B cells were to be detected for the first time, followed by T lymphocytes approximately 20 days after transplantation. Besides the fact that neutrophils were undetectable in the antibody treated groups, the peripheral blood revealed no significant changes between the neutropenic mice and the control group at any point of time. At the bone marrow level, an increase of LSK and granulocyte-macrophage progenitors (GMPs) at the expense of megakaryocyte erythrocyte progenitor cells (MEPs) was found in neutropenic mice. Common lymphoid progenitors (CLPs), however, were not significantly different. Conclusions: The engraftment of wild type donor cells after hematopoietic stem cell transplantation into NODSCIDcγ−/− mice started with the production of monocytes and neutrophils. B-lymphocytes were detectable by day 14 after transplantation. The production of T-cells started around day 20. Continuous antibody-mediated neutropenia did not significantly delay lymphoid regeneration. Although the marrow of neutropenic mice displayed increased proliferation of granulocyte progenitors, CLPs were unchanged. We conclude that the detection of donor-derived lymphocytes in the host peripheral blood is a relatively early event after LSK transplantation. Moreover, antibody induced neutropenia is not sufficient to induce sustainable changes in early hematopoietic fate decisions on the bone marrow level. Disclosures: No relevant conflicts of interest to declare.
Engagement of αIIbβ3 (GPIIb/IIIa) with ανβ3 Integrin Mediates Interaction of Melanoma Cells with Platelets
2011-11-19

A mutual relationship exists between metastasizing tumor cells and components of the coagulation cascade. The exact mechanisms as to how platelets influence blood-borne metastasis, however, remain poorly understood. Here, we used murine B16 melanoma cells to observe functional aspects of how platelets contribute to the process of hematogenous metastasis. We found that platelets interfere with a distinct step of the metastasis cascade, as they promote adhesion of melanoma cells to the endothelium in vitro under shear conditions. Constitutively active platelet receptor GPIIb/IIIa (integrin αIIbβ3) expressed on Chinese hamster ovary cells promoted melanoma cell adhesion in the presence of fibrinogen, whereas blocking antibodies to aνβ3 integrin on melanoma cells or to GPIIb/IIIa significantly reduced melanoma cell adhesion to platelets. Furthermore, using intravital microscopy, we observed functional platelet-melanoma cell interactions, as platelet depletion resulted in significantly reduced melanoma cell adhesion to the injured vascular wall in vivo. Using a mouse model of hematogenous metastasis to the lung, we observed decreased metastasis of B16 melanoma cells to the lung by treatment with a mAb blocking the aν subunit of aνβ3 integrin. This effect was significantly reduced when platelets were depleted in vivo. Thus, the engagement of GPIIb/IIIa with aνβ3 integrin interaction mediates tumor cell-platelet interactions and highlights how this interaction is involved in hematogenous tumor metastasis.
An Allosteric Coagonist Model for Propofol Effects on α1β2γ2L γ-Aminobutyric Acid Type A Receptors
2011-11-19

Background Propofol produces its major actions via γ-aminobutyric acid type A (GABA(A)) receptors. At low concentrations, propofol enhances agonist-stimulated GABA(A) receptor activity, and high propofol concentrations directly activate receptors. Etomidate produces similar effects, and there is convincing evidence that a single class of etomidate sites mediate both agonist modulation and direct GABA(A) receptor activation. It is unknown if the propofol binding site(s) on GABA(A) receptors that modulate agonist-induced activity also mediate direct activation. Methods GABA(A) α1β2γ2L receptors were heterologously expressed in Xenopus oocytes and activity was quantified using voltage clamp electrophysiology. We tested whether propofol and etomidate display the same linkage between agonist modulation and direct activation of GABA(A) receptors by identifying equiefficacious drug solutions for direct activation. We then determined whether these drug solutions produce equal modulation of GABA-induced receptor activity. We also measured propofol-dependent direct activation and modulation of low GABA responses. Allosteric coagonist models similar to that established for etomidate, but with variable numbers of propofol sites, were fitted to combined data. Results Solutions of 19 μM propofol and 10 μM etomidate were found to equally activate GABA(A) receptors. These two drug solutions also produced indistinguishable modulation of GABA-induced receptor activity. Combined electrophysiological data behaved in a manner consistent with allosteric coagonist models with more than one propofol site. The best fit was observed when the model assumed three equivalent propofol sites. Conclusions Our results support the hypothesis that propofol, like etomidate, acts at GABA(A) receptor sites mediating both GABA modulation and direct activation.
Arabidopsis lysin-motif proteins LYM1 LYM3 CERK1 mediate bacterial peptidoglycan sensing and immunity to bacterial infection
2011-11-21

Recognition of microbial patterns by host pattern recognition receptors is a key step in immune activation in multicellular eukaryotes. Peptidoglycans (PGNs) are major components of bacterial cell walls that possess immunity-stimulating activities in metazoans and plants. Here we show that PGN sensing and immunity to bacterial infection in Arabidopsis thaliana requires three lysin-motif (LysM) domain proteins. LYM1 and LYM3 are plasma membrane proteins that physically interact with PGNs and mediate Arabidopsis sensitivity to structurally different PGNs from Gram-negative and Gram-positive bacteria. lym1 and lym3 mutants lack PGN-induced changes in transcriptome activity patterns, but respond to fungus-derived chitin, a pattern structurally related to PGNs, in a wild-type manner. Notably, lym1 , lym3 , and lym3 lym1 mutant genotypes exhibit supersusceptibility to infection with virulent Pseudomonas syringae pathovar tomato DC3000. Defects in basal immunity in lym3 lym1 double mutants resemble those observed in lym1 and lym3 single mutants, suggesting that both proteins are part of the same recognition system. We further show that deletion of CERK1, a LysM receptor kinase that had previously been implicated in chitin perception and immunity to fungal infection in Arabidopsis , phenocopies defects observed in lym1 and lym3 mutants, such as peptidoglycan insensitivity and enhanced susceptibility to bacterial infection. Altogether, our findings suggest that plants share with metazoans the ability to recognize bacterial PGNs. However, as Arabidopsis LysM domain proteins LYM1, LYM3, and CERK1 form a PGN recognition system that is unrelated to metazoan PGN receptors, we propose that lineage-specific PGN perception systems have arisen through convergent evolution.