julilili42/papers huggingface dataset:
Adoptive Transfer of Hexon-Specific T-Cells as a Treatment of Adenovirus Reactivation Following Allogeneic Stem Cell Transplantation.
2009-11-20

Abstract Abstract 796 In pediatric patients human adenovirus (HAdV) was identified as a common viral pathogen responsible for significant morbidity and mortality post allo SCT. Antiviral chemotherapy is often insufficient. Given that T-cell immunity is crucial for protection against adenoviral infection/reactivation, cellular immunotherapy is a promising therapeutic option. The capsid protein Hexon has been shown to contain immunodominant T-cell epitopes, with T-cell responses in the majority of the healthy population. Therefore a prospective phase I/II clinical study was performed analysing safety and feasibility of adoptive Hexon-specific T-cell transfer in patients after allogeneic SCT and HAdV infection refractory to Cidofovir treatment. Hexon-specific T-cells were isolated from the SCT-donor by using the IFNγ secretion system and small T-cell populations were immediately infused, without in vitro expansion steps. Fourty pediatric and adult patients with a mean age of 15 years were treated according to the study protocol after haploidentical, matched unrelated and matched sibling donor SCT between day 11 and 327 post SCT. The T-cell dose varied from 300-25000 T-cells/kg. No acute toxicitiy was observed. In two patients GvHD °I-°II of the skin occured within two weeks after administration of specific T-cells, one patient also developed GvHD of the gut. In vivo T-cell responses were absent in all patients before adoptive T-cell transfer and detectable in 70% of evaluable patients within the first weeks after adoptive transfer, associated with a clinical and/or virological response to the adoptive T-cell transfer. However, in patients with adenoviral disease response rate was lower and 6 of 14 evaluable patients succumbed with the infection within few days, in spite of adoptive immunotherapy. This lead to the assumption, that adoptive treatment in patients with severe infection related morbidity was to late during the course of infection. In conclusion we could show that adoptive immunotherapy is safe, feasible and a promising therapeutic option in patients with HAdV infection. Infusion of small IFNγ producing Hexon-specific T-cells populations resulted in an in vivo expansion of specific T-cells in the majority of cases. Emergence of in vivo T-cell responses was closely associated with a clearance or reduction of the viral load. Disclosures: No relevant conflicts of interest to declare.
Shift to a New Donor Does Not Improve the Outcome After Second Allogeneic Stem Cell Transplantation (alloSCT) in Acute Leukemia Relapse After a First Allosct – a Risk Factor Analysis by the German Stem Cell Registry (DRST).
2009-11-20

Abstract Abstract 3328 Poster Board III-216 Introduction Relapse is a major cause of treatment failure after alloSCT against acute leukaemia, and no standard treatment has been established in this challenging situation. The introduction of reduced conditioning regimens, and the broader availability of alternative donors have increased the possibilities to perform a second alloSCT as salvage treatment, using different preparative regimen and/or different stem cell donors. Methods To evaluate the role of a second alloSCT (tx2) for the treatment of relapse after first alloSCT (tx1), we performed a nationwide retrospective analysis based on the German registry for stem cell transplantation (DRST). Datasets were completed by the reporting centres on request, following a specifically designed questionnaire. Results 212 patients (69% AML, 31% ALL), from 23 centres were included. Median age at tx1 was 37y. Donor at tx1 were HLA identical siblings (41%), matched unrelated (39%), mismatched family or unrelated (17%) or syngeneic donors (3%). Conditioning intensity at tx1 was standard (SIC, 62%), intermediate (intC, 25%) or reduced (RIC, 13%). Median remission after tx1 was 7 months, median time from relapse to tx2 was 74d. At tx2, patients were aplastic (4%), in CR (20%) or showed active disease (76%). In 59%, the same donor was used for tx1 and tx2, whereas a different donor was chosen in 41%. Conditioning at tx1/tx2 were SIC/SIC (14%), intC/intC (10%), (RIC/RIC (10%), less intensive at tx2 (mostly intC or RIC after SIC, 58%), or more intensive at tx2 (SIC after RIC or intC, 8%). Following tx2, CR was achieved in 56% of patients, out of which 81% relapsed again. Hence, leukemia was the most frequent cause of death. With a median FU of 23 months after tx2, median OS after tx2 is 117d. In a univariate analysis (log rank), OS after tx2 depended on stage at tx1 (CR vs. active disease, p&lt;.001), stage at tx2 (CR vs. aplastic/active disease, p=.011) and duration of remission after tx1 (&lt;=6m (1y OS 5%) vs. 6-12m (15%) vs. &gt;12m (31%), p&lt;.001). No significant difference was observed regarding age ( median), AML vs. ALL, family versus unrelated donor, or time point of alloSCT (2002). Shift to an alternative donor did not improve the results either. In a multivariate analysis (Cox Regression Model), time of remission after tx1 was the only significant factor for OS (p&lt;.001, hazard ratio .51, 95%CI .49-.74). Conclusion Survival of acute leukemia after second allogeneic SCT is determined by the duration of remission after tx1. Using an alternative donor for tx2 did not improve the results in our series. Further analysis is required to evaluate the role of RIC regimen for tx2. Disclosures No relevant conflicts of interest to declare.
Allogeneic Stem Cell Transplantation for Hodgkin's Disease From Sibling and Unrelated Donors: The German Cooperative Transplantation Study Group Experience.
2009-11-20

Abstract Abstract 2293 Poster Board II-270 Introduction: Although modern chemotherapy regimens achieve a high cure rate in primary Hodgkin's disease and relapsed patients can be salvaged by high dose chemotherapy with autologous stem cell transplantation there remains a subgroup of patients with early relapse despite high dose chemotherapy. The prognosis of these patients is dismal with further chemotherapy. Allogeneic transplantation has the potential to exert an alloimmune response against lymphoma cells and has therefor been offered to patients with relapsed or refractory Hodgkin's disease, in particular when a matched sibling donor was available. However only limited information on the feasability of allogeneic transplantion from an unrelated donor is available. Methods: We performed a retrospective analysis of allogeneic transplants for Hodgkins disease within the German Cooperative Transplantation Study Group. 18 centres have provided data on patient and donor characteristics, transplant procedure and outcome. Survival data were analysed by Kaplan-Meier and tested for differences by log rank test. Cumulative incidences for relapse, non-relapse mortality and graft-versus-host-disease were calculated in a competing risk model. Results: 79 patients with a median age of 30 years (range 14-59) were included. 65 (82%) patients had failed a previous autologous transplantation 582 days (median) before allotransplantation. Disease status at transplantation was CR in 17.6%, PR in 54.0%, stable disease in 9.5%, PD in 12.2%, and untreated relapse in 6.8%. Donors were matched related in 33%, mismatched related in 5%, matched unrelated in 42% and mismatched unrelated in 20%. With a median follow up of 19 months for surviving patients the median overall survival (OS) after allotransplant was 42 months with a 2 year survival of 51%. Non-relapse mortality was 21.1% after 12 and 24 months. The median progression-free survival was 14.6 months with a 2 year PFS of 42.0%. Patients relapsing after an autologous transplantation had a significantly better OS (median 53.7 vs 8.4 months, p=0.029) and PFS (22.0 vs 7.5 months, p=0.039) than patients without a prior autograft. No significant difference was seen for OS or PFS regarding the use of related or unrelated donors or disease status at transplant. Conclusions: Allogenic transplantation is a feasible option for high-risk patients with relapsed or refractory Hodgkins disease in particular after failing an autograft. Non-relapse mortality appears to be acceptable in view of the intensive prior treatment. Probabilities for overall survival and progression-free survival were similar after transplantation from a related or unrelated donor. Further optimisation strategies have to focus on on efforts to reduce the high relapse-rate after transplantation, thereby potentially increasing overall and progression free survival. Disclosures: No relevant conflicts of interest to declare.
N-{4-[4-(4-Fluorophenyl)-1-(2-methoxyethyl)-2-methylsulfanyl-1H-imidazol-5-yl]-2-pyridyl}-2-methyl-3-phenylpropionamide
2009-11-20

In the crystal structure of the title compound, C(28)H(29)FN(4)O(2)S, the imidazole ring makes dihedral angles of 11.85 (7), 73.33 (7) and 22.83 (8)° with the 4-fluoro-phenyl, pyridine and phenyl rings, respectively. The 4-fluoro-phenyl ring makes dihedral angles of 77.91 (7) and 26.93 (8)° with the pyridine and phenyl rings, respectively. The phenyl and pyridine rings are nearly perpendicular, making a dihedral angle of 86.47 (9)°. The crystal packing shows an inter-molecular N-H⋯O hydrogen-bonding inter-action between the N-H and carbonyl groups of the amide functions.
The FLT3-Inhibitors Midostaurin, Sunitinib, Sorafenib, and TKI258 Differentially Affect NK Cell-Mediated Immunesurveillance of Acute Myeloid Leukemia.
2009-11-20

Abstract Abstract 3785 Poster Board III-721 FLT3 is a receptor tyrosine kinase with an important role in hematopoietic progenitor cell survival and proliferation. The discovery of internal tandem duplication mutations (ITD) in FLT3 was a major breakthrough in understanding the role of abnormally activated FLT3 in myeloid transformation. Between 15% and 34% of AML patients show FLT3-ITD mutations, and thus the inhibition of FLT3 in combination with chemotherapeutic agents may be a promising stragety in the treatment of Acute Myeloid Leukemia (AML). Several protein kinase inhibitors (PKI) targeting FLT3 like e.g. Midostaurin, Sunitinib, Sorafenib, and TKI258 are currently under preclinical and/or clinical evaluation (http://clinicaltrials.gov/ct2/results?term=AML+and+FLT3). Since those PKI, besides targeting their eponymous enzyme FLT3, also inhibit signaling via other molecules they may impair the effector function of various components of anti-tumor immunity. NK cells as part of the innate immune system play an important role in the immune surveillance of tumors due to their ability to directly kill target cells and to shape adaptive immune responses by secreting cytokines like IFN-γ. Clinical evidence for the particularly important role of NK cells in leukemia has recently been provided by studies of haploidentical stem cell transplantation (Ruggeri et al., Science 2002). We report here that CD107a expression as a surrogate marker for degranulation of NK cells within PBMC is inhibited by pharmacological concentrations of Sorafenib (10μg/ml) and Midostaurin (2μg/ml), but not by Sunitinib (200ng/ml) and TKI258 (125ng/ml). In line, pharmacological concentrations of Sunitinib and TKI258 did not affect NK cell cytotoxicity and IFN-γ production in cocultures with leukemia cells. Sorafenib and Midostaurin caused a clear concentration-dependent inhibition of NK cell cytokine production in response to target cells both in resting and in IL-2 activated state (92% and 66%, respectively at plasma peak levels). Furthermore, pharmacological concentrations of Sorafenib and Midostaurin also reduced lysis of leukemia cells by NK cells (54% and 58%, respectively, E:T ratio 10:1) and thus generally compromised NK cell reactivity. Analysis of NK cell signaling revealed that Sorafenib, but not Midostaurin decreased phosphorylation of PI3K and ERK which are important regulators of NK cell reactivity. Thus, Midostaurin inhibits yet undefined signaling events which are crucial for NK effector functions, but are independent of the “classical” PI3K – Rac – PAK – MEK – ERK pathway and are presently under study. Moreover, in light of the important role of NK cells in the immune surveillance of leukemia and the differential influence of clinically used FLT3-inhibitors on NK cell functions our data indicate that the choice and dosing of the most suitable compound in the treatment of AML requires further characterization and careful consideration. Disclosures: No relevant conflicts of interest to declare.
Consequences of 4-1BB-4-1BB Ligand Interaction for NK Cell Anti-Tumor Immunity: Opposite Effects of Seemingly Analogue Molecules in Mice and Men.
2009-11-20

Abstract Abstract 279 In mouse models, stimulation of the TNF receptor family member 4-1BB/CD137 on cytotoxic lymphocytes by agonistic antibodies potently stimulated anti-tumor immunity, which has led to the development of humanized agonistic 4-1BB mAb that are presently being evaluated in clinical phase I/II studies (www.clinicaltrials.gov, keyword: CD137). However, seemingly analogue immunoregulatory molecules may mediate different effects in mice and men, and in humans yet nothing is known regarding the role of 4-1BB in NK cell reactivity. NK cells play an important role in tumor immunosurveillance, and largely contribute to the success of therapeutic strategies like (haploidentical) stem cell transplantation (SCT) or application of monoclonal antibodies like Rituximab by mediating graft versus leukemia activity and performing antibody-dependent cellular cytotoxicity (ADCC). Here we analyzed the expression of 4-1BB in human NK cells and compared the effect of 4-1BB signaling on effector functions of NK cells in mice and men. While being absent in resting state, both human and mouse NK cells acquire expression of 4-1BB at similar levels with comparable kinetics upon activation. Next we cultured human and mouse NK cells with target cells transfected with human and mouse 4-1BB ligand (4-1BBL) and analyzed the effect of 4-1BB on NK cell effector functions. 4-1BB – 4-1BBL interaction enhanced effector functions of mouse NK cells, while degranulation, cytotoxicity and cytokine production of human NK cells were substantially impaired (all p&lt;0.01, Student's T-test). In line, employing primary leukemia cells from patients with AML (n= 65) and CLL (n=49), which were found to express 4-1BBL in 35% and 100%, respectively, we found that blocking 4-1BB-4-1BBL interaction markedly enhanced granule mobilization, cytotoxicity and interferon-g production of allogenic and autologous human NK cells in response to leukemia cells. In CLL, this inhibitory effect of 4-1BB-4-1BBL interaction on NK cell reactivity was observed both with regard to direct and Rituximab-induced cytotoxicity and cytokine production. Together, our data implicate that one should exercise caution in applying anti-4-1BB therapeutically, underline the necessity of detailed analyses regarding the function of seemingly analogue immunoregulatory molecules in mice compared to men and demonstrate that blocking 4-1BBL-4-1BB interaction may serve to enhance NK cell reactivity in therapeutic settings like allogenic SCT and antibody-treatment of malignancies in humans. Disclosures: No relevant conflicts of interest to declare.
Identification of Cyclin D1-Dependent Genes by Gene Expression Profiling in MCL Cell Lines and Primary Cases.
2009-11-20

Abstract Abstract 3936 Poster Board III-872 Introduction The hallmark of MCL is overexpression of cyclin D1 due to the t(11;14). As cyclin D1 plays a central role in cell cycle regulation and influences the activity of several transcription factors, its overexpression is believed to initiate MCL lymphomagenesis. To dissect the transcriptional network regulated by cyclin D1, and to assess the relationship of cyclin D1 to genes comprising the recently described MCL proliferation signature, the consequences of cyclin D1 knockdown were analyzed by comparative gene expression profiling. Materials and Methods Four MCL cell lines, Granta 519, Jeko-1, Rec-1 and Z-138 were transduced with lentivirus containing the cyclin D1 shRNA or with empty lentivirus in triplicates. At day seven after infection, RNA was extracted and used for Gene Chip expression analysis (U133 Plus 2.0 arrays/ Affymetrix). After robust multi-array average (RMA) preprocessing, genes which were differentially expressed in all four cell lines were identified using BioConductor software. Validation was performed by correlating cyclin D1 levels with candidate gene expression by qRT-PCR in 10 primary MCL cases. Results To identify genes regulated by cyclin D1 in all four cell lines, statistical analysis applying a false discovery rate of 10% was performed, thereby accepting only genes with a &gt;1,1 and &lt;0,9 fold ratio and an average expression &gt;25. We identified 344 genes regulated after cyclin D1 knockdown (93 upregulated, 251 downregulated). Classification of the differentially expressed genes to biological processes revealed overrepresentation of genes involved in replication (23,0%), chromatin packaging and remodelling (12,5%), signal transduction (10,5%), metabolism (9,9%), transcription (9,6%) and cell cycle (6,4%). Of the 20 genes comprising the MCL proliferation signature (Rosenwald et al., Blood 2003), 10 were identified as cyclin D1 dependent. These genes were validated in MCL with high vs. low levels of cyclin D1 mRNA. Although there was a direct correlation between these 10 genes and cyclin D1 levels, it is notable that there was no correlation between the proliferation rate as assessed with MiB1 and the level of cyclin D1 expression Conclusions Comparative gene expression profiling before and after knockdown of cyclin D1 in MCL cell lines reveals a complex transcriptional network influenced by cyclin D1 expression levels. We also show that 10 of the 20 genes comprising the MCL proliferation signature are cyclin D1-dependent. These genes showed good correlation with cyclin D1 mRNA levels in primary cases, however, no correlation with proliferation rate was identified, suggesting cyclin D1-independent mechanisms governing proliferation in MCL. The identification of cyclin D1-dependent genes assists in our understanding of the contribution of cyclin D1 overexpression to the biology and clinical course of MCL. Disclosures: No relevant conflicts of interest to declare.
Elevated Heat Shock Protein 70 (HSP70) Serum Levels After Tumor Radiofrequency Ablation Might Represent a Favorable Prognostic Marker.
2009-11-20

Abstract Abstract 4748 Introduction Radiofrequency (RF) ablation is a safe and effective method to locally treat malignancies of the liver, kidney and more recently lung. For the treatment of small tumors, long term results are comparable with outcome after surgical resection and better than current chemotherapies. RF-ablation has now been reported to induce heat shock protein (HSP) expression on sublethally damaged hepatocytes. HSPs are potent alarm signals for the immune system causing i.e. activation of T cells and dendritic cells. In addition to triggering immune responses directed against HSPs themselves, HSPs can carry antigens derived from those cells of which HSPs originated and thereby elicit specific immune reactions against these cellular epitopes. Patients and Methods We here analyzed serum samples of 22 patients to evaluate the systemic release of HSP70 using a specific HSP70 ELISA. Patients were followed for a median of 30 months until death or three years after the last RF-treatment. As a control group, sera from 20 patients undergoing diagnostic liver biopsy were screened. Results The median increase of HSP70 in serum comparing levels before and one day after the procedures was 1.6-fold in the RF-ablation group, while no soluble HSP-70 could be detected in the control group before and after the biopsy. Nine patients showed a higher than two-fold increase of HSP70 in the serum after ten sessions of RF-ablation compared to levels prior to treatment. No correlation of HSP70 levels with tumor volume, the ablated non-malignant tissue or the total size of the necrosis was observed. In the subgroup of patients with elevated HSP-70 serum levels, 67% (6 out of 9) were alive at the end of follow up with only one suffering from progressive disease. In contrast, 61% (8 out of 13) of the other patients suffered from progressive disease or had deceased at the end of follow-up. Conclusion RF-ablation not only induces cellular HSP expression but also can lead to a systemic release of serum HSP70. Patients with strong increases in HSP-70 serum levels tended to have a better survival than patients without induction of HSP-70 in the serum. Thus, immunomodulation might represent an additional beneficial effect of RF-ablation besides local tumor destruction, since HSPs are strong stimuli for the immune system and can mediate tumor-specific T cell immunity. Disclosures: No relevant conflicts of interest to declare.
Rapid Reconstitution of Human Antibody Secreting Cells After Haploidentical Allogeneic Stem Cell Transplantation.
2009-11-20

Abstract Abstract 3682 Poster Board III-618 Innate immunity including granulocytes, monocytes, and NK cells is reported to recover rapidly after allogeneic stem cell transplantation within weeks. In contrast, adaptive immunity, including T- and B-cells, has delayed recovery over months. In murine models innate type marginal zone and B1 B cells, established at fetal age and providing natural antibodies, are distinguished from adaptive B2 or follicular B cells. A crucial maturation and survival factor for adaptive murine B cells was shown to be TNF-family member BAFF (B cell-activating factor), while development of innate B1 B cells is BAFF independent. Kinetics in reconstitution of innate and adaptive immunity after ablation in adults may give insight into hierarchy and attribution to innate and adaptive immunity of defined lymphocyte populations. Reconstitution of lymphopoiesis after CD3 and CD19 depleted haploidentical stem cell transplantation was analyzed in 10 patients, which received monoclonal anti-CD3 antibody OKT3 as immunosuppressant only. This model may enable detailed in vivo evaluation of de novo B cell formation. Weekly samples before and after reduced-intensity conditioning were analyzed by flow cytometry for absolute numbers of T-cell, NK-, and B-cell subsets. Their origin of host or donor hematopoiesis was differentiated by HLA-FACS. Antibody secreting cells (ASC) were enumerated by ELISPOT. Plasma cytokine concentrations were determined by bead based arrays and ELISA. Complete reconstitution of allogeneic NK cells was found at day +21 after transplantation. CD4+ and CD8+ T-cells and their subsets had delayed reconstitution with less then 100 cells/μl at 3 months after transplantation. CD19+ B-lymphocytes of naïve and memory phenotype (&gt;0,5% of all lymphocytes) were detected not before day +60. In contrast, complete reconstitution of antibody-secreting cells after a nadir (&lt;0,05/μl) was observed at day +14. Absolute numbers of ASC were comparable to those of healthy controls (d+14: 72 ASC/μl vs. control: 12 ASC/μl). ASC secreting the isotypes IgM and IgA were more prevalent than IgG compared to controls (time increase: IgM 20; IgA 10; IgG 2,9). These ASC appear CD19low/neg, CD38+, and intracellular Ig+ in flow cytometry and carried donor HLA-haplotype. Reconstitution of ASC occurred without detectable circulating T-cells and before increase of BAFF concentrations were observed. In summary, the rapid and complete reconstitution of peripheral blood ASC after allogeneic transplantation, far proceeding detection of naïve and memory type B-cells, is a novel observation. Incidence before T-cell reconstitution and increase in BAFF concentrations indicates a T-cell and BAFF independent mechanism allocating these early ASC to innate immunity, potentially maintaining natural antibody levels. Disclosures: No relevant conflicts of interest to declare.