836 research outputs found
Immunologic Predictors for Clinical Responses During Immune Checkpoint Blockade in Patients With Myelodysplastic Syndromes
PURPOSE: The aim of this study is to determine immune-related biomarkers to predict effective antitumor immunity in myelodysplastic syndrome (MDS) during immunotherapy (IMT, αCTLA-4, and/or αPD-1 antibodies) and/or hypomethylating agent (HMA).
EXPERIMENTAL DESIGN: Peripheral blood samples from 55 patients with MDS were assessed for immune subsets, T-cell receptor (TCR) repertoire, mutations in 295 acute myeloid leukemia (AML)/MDS-related genes, and immune-related gene expression profiling before and after the first treatment.
RESULTS: Clinical responders treated with IMT ± HMA but not HMA alone showed a significant expansion of central memory (CM) CD8+ T cells, diverse TCRβ repertoire pretreatment with increased clonality and emergence of novel clones after the initial treatment, and a higher mutation burden pretreatment with subsequent reduction posttreatment. Autophagy, TGFβ, and Th1 differentiation pathways were the most downregulated in nonresponders after treatment, while upregulated in responders. Finally, CTLA-4 but not PD-1 blockade attributed to favorable changes in immune landscape.
CONCLUSIONS: Analysis of tumor-immune landscape in MDS during immunotherapy provides clinical response biomarkers
A Novel T-Cell Engaging Bi-specific Antibody Targeting the Leukemia Antigen PR1/HLA-A2
Despite substantial advances in the treatment of acute myeloid leukemia (AML), only 30% of patients survive more than 5 years. Therefore, new therapeutics are much needed. Here, we present a novel therapeutic strategy targeting PR1, an HLA-A2 restricted myeloid leukemia antigen. Previously, we have developed and characterized a novel T-cell receptor-like monoclonal antibody (8F4) that targets PR1/HLA-A2 and eliminates AML xenografts by antibody-dependent cellular cytotoxicity (ADCC). To improve the potency of 8F4, we adopted a strategy to link T-cell cytotoxicity with a bi-specific T-cell-engaging antibody that binds PR1/HLA-A2 on leukemia and CD3 on neighboring T-cells. The 8F4 bi-specific antibody maintained high affinity and specific binding to PR1/HLA-A2 comparable to parent 8F4 antibody, shown by flow cytometry and Bio-Layer Interferometry. In addition, 8F4 bi-specific antibody activated donor T-cells in the presence of HLA-A2+ primary AML blasts and cell lines in a dose dependent manner. Importantly, activated T-cells lysed HLA-A2+ primary AML blasts and cell lines after addition of 8F4 bi-specific antibody. In conclusion, our studies demonstrate the therapeutic potential of a novel bi-specific antibody targeting the PR1/HLA-A2 leukemia-associated antigen, justifying further clinical development of this strategy
Effective Rheology of Bubbles Moving in a Capillary Tube
We calculate the average volumetric flux versus pressure drop of bubbles
moving in a single capillary tube with varying diameter, finding a square-root
relation from mapping the flow equations onto that of a driven overdamped
pendulum. The calculation is based on a derivation of the equation of motion of
a bubble train from considering the capillary forces and the entropy production
associated with the viscous flow. We also calculate the configurational
probability of the positions of the bubbles.Comment: 4 pages, 1 figur
Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector
Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
Search for new physics with same-sign isolated dilepton events with jets and missing transverse energy
A search for new physics is performed in events with two same-sign isolated
leptons, hadronic jets, and missing transverse energy in the final state. The
analysis is based on a data sample corresponding to an integrated luminosity of
4.98 inverse femtobarns produced in pp collisions at a center-of-mass energy of
7 TeV collected by the CMS experiment at the LHC. This constitutes a factor of
140 increase in integrated luminosity over previously published results. The
observed yields agree with the standard model predictions and thus no evidence
for new physics is found. The observations are used to set upper limits on
possible new physics contributions and to constrain supersymmetric models. To
facilitate the interpretation of the data in a broader range of new physics
scenarios, information on the event selection, detector response, and
efficiencies is provided.Comment: Published in Physical Review Letter
Regulation of the cd38 promoter in human airway smooth muscle cells by TNF-α and dexamethasone
<p>Abstract</p> <p>Background</p> <p>CD38 is expressed in human airway smooth muscle (HASM) cells, regulates intracellular calcium, and its expression is augmented by tumor necrosis factor alpha (TNF-α). CD38 has a role in airway hyperresponsiveness, a hallmark of asthma, since deficient mice develop attenuated airway hyperresponsiveness compared to wild-type mice following intranasal challenges with cytokines such as IL-13 and TNF-α. Regulation of CD38 expression in HASM cells involves the transcription factor NF-κB, and glucocorticoids inhibit this expression through NF-κB-dependent and -independent mechanisms. In this study, we determined whether the transcriptional regulation of CD38 expression in HASM cells involves response elements within the promoter region of this gene.</p> <p>Methods</p> <p>We cloned a putative 3 kb promoter fragment of the human <it>cd38 </it>gene into pGL3 basic vector in front of a luciferase reporter gene. Sequence analysis of the putative <it>cd38 </it>promoter region revealed one NF-κB and several AP-1 and glucocorticoid response element (GRE) motifs. HASM cells were transfected with the 3 kb promoter, a 1.8 kb truncated promoter that lacks the NF-κB and some of the AP-1 sites, or the promoter with mutations of the NF-κB and/or AP-1 sites. Using the electrophoretic mobility shift assays, we determined the binding of nuclear proteins to oligonucleotides encoding the putative <it>cd38 </it>NF-κB, AP-1, and GRE sites, and the specificity of this binding was confirmed by gel supershift analysis with appropriate antibodies.</p> <p>Results</p> <p>TNF-α induced a two-fold activation of the 3 kb promoter following its transfection into HASM cells. In cells transfected with the 1.8 kb promoter or promoter constructs lacking NF-κB and/or AP-1 sites or in the presence of dexamethasone, there was no induction in the presence of TNF-α. The binding of nuclear proteins to oligonucleotides encoding the putative <it>cd38 </it>NF-κB site and some of the six AP-1 sites was increased by TNF-α, and to some of the putative <it>cd38 </it>GREs by dexamethasone.</p> <p>Conclusion</p> <p>The EMSA results and the cd38 promoter-reporter assays confirm the functional role of NF-κB, AP-1 and GREs in the cd38 promoter in the transcriptional regulation of CD38.</p
Peccei-Quinn NMSSM in the light of 125 GeV Higgs
We study the phenomenology of the Peccei-Quinn invariant extension of the
next-to-minimal supersymmetric standard model (NMSSM) in view of the recent
discovery of a 125 GeV Higgs boson. The minimal model having no quadratic and
cubic terms of the NMSSM singlet field predicts a light singlino-like lightest
supersymmetric particle (LSP). The model is strongly constrained by the Higgs
invisible decay and the dark matter characteristic of the LSP, while some
constraints can be relaxed by assuming that the saxion, the CP-even companion
of the axion in the Peccei-Quinn sector, causes a late-time entropy production
diluting the thermal LSP density. The collider signal of the model contains
multi-jet and plus missing energy, which can be discovered in the early
stage of the 14 TeV LHC running.Comment: 40 pages, 10 figures, 6 tables. v3: references added, several
statements added and corrected, comments on the small tadpole soft term added
in sec. 2.
An Active Site Aromatic Triad in Escherichia coli DNA Pol IV Coordinates Cell Survival and Mutagenesis in Different DNA Damaging Agents
DinB (DNA Pol IV) is a translesion (TLS) DNA polymerase, which inserts a
nucleotide opposite an otherwise replication-stalling
N2-dG lesion in vitro, and
confers resistance to nitrofurazone (NFZ), a compound that forms these lesions
in vivo. DinB is also known to be part of the cellular
response to alkylation DNA damage. Yet it is not known if DinB active site
residues, in addition to aminoacids involved in DNA synthesis, are critical in
alkylation lesion bypass. It is also unclear which active site aminoacids, if
any, might modulate DinB's bypass fidelity of distinct lesions. Here we
report that along with the classical catalytic residues, an active site
“aromatic triad”, namely residues F12, F13, and Y79, is critical for
cell survival in the presence of the alkylating agent methyl methanesulfonate
(MMS). Strains expressing dinB alleles with single point
mutations in the aromatic triad survive poorly in MMS. Remarkably, these strains
show fewer MMS- than NFZ-induced mutants, suggesting that the aromatic triad, in
addition to its role in TLS, modulates DinB's accuracy in bypassing
distinct lesions. The high bypass fidelity of prevalent alkylation lesions is
evident even when the DinB active site performs error-prone NFZ-induced lesion
bypass. The analyses carried out with the active site aromatic triad suggest
that the DinB active site residues are poised to proficiently bypass distinctive
DNA lesions, yet they are also malleable so that the accuracy of the bypass is
lesion-dependent
Measurement of VH, H → b b ¯ production as a function of the vector-boson transverse momentum in 13 TeV pp collisions with the ATLAS detector
Cross-sections of associated production of a Higgs boson decaying into bottom-quark pairs and an electroweak gauge boson, W or Z, decaying into leptons are measured as a function of the gauge boson transverse momentum. The measurements are performed in kinematic fiducial volumes defined in the `simplified template cross-section' framework. The results are obtained using 79.8 fb-1 of proton-proton collisions recorded by the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 13 TeV. All measurements are found to be in agreement with the Standard Model predictions, and limits are set on the parameters of an effective Lagrangian sensitive to modifications of the Higgs boson couplings to the electroweak gauge bosons
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