3,191 research outputs found
The therapeutic promise of disrupting the PD-1/PD-L1 immune checkpoint in cancer: unleashing the CD8 T cell mediated anti-tumor activity results in significant, unprecedented clinical efficacy in various solid tumors.
The role of immune checkpoints in modulating the magnitude as well as the functional profile of T cell responses is increasingly understood in molecular detail. Antibody-mediated blockade of co-inhibitory receptors has been shown to restore T cell function in both chronic viral infections and cancer. The latter has been successfully translated to new therapeutic options in the treatment of cancer. Indeed, monoclonal antibodies blocking either CTLA-4 or PD-1 have recently been approved for the treatment of metastatic melanoma in the United States, Europe and Japan. In this commentary, we summarize and put into perspective five letters recently published back to back in the November 27 (2014) issue of Nature reporting on different immunological and clinical aspects of blockade of the PD-1/PD-L1 pathway in tumor bearing hosts. Notably, treatment with anti-PD-L1 blocking antibody was shown result in profound clinical responses in patients with several solid tumor including bladder, lung and head and neck carcinomas among others. These five simultaneous publications highlight the tremendous therapeutic potential of targeting the PD-1/PD-L1 immune checkpoint and emphasize the need to identify appropriate biomarkers to guide their optimal clinical application
MART-1 peptide vaccination plus IMP321 (LAG-3Ig fusion protein) in patients receiving autologous PBMCs after lymphodepletion: results of a Phase I trial.
BACKGROUND: Immunotherapy offers a promising novel approach for the treatment of cancer and both adoptive T-cell transfer and immune modulation lead to regression of advanced melanoma. However, the potential synergy between these two strategies remains unclear.
METHODS: We investigated in 12 patients with advanced stage IV melanoma the effect of multiple MART-1 analog peptide vaccinations with (nâ=â6) or without (nâ=â6) IMP321 (LAG-3Ig fusion protein) as an adjuvant in combination with lymphodepleting chemotherapy and adoptive transfer of autologous PBMCs at day (D) 0 (Trial registration No: NCT00324623). All patients were selected on the basis of ex vivo detectable MART-1-specific CD8 T-cell responses and immunized at D0, 8, 15, 22, 28, 52, and 74 post-reinfusion.
RESULTS: After immunization, a significant expansion of MART-1-specific CD8 T cells was measured in 83% (nâ=â5/6) and 17% (nâ=â1/6) of patients from the IMP321 and control groups, respectively (Pâ<â0.02). Compared to the control group, the mean fold increase of MART-1-specific CD8 T cells in the IMP321 group was respectively >2-, >4- and >6-fold higher at D15, D30 and D60 (Pâ<â0.02). Long-lasting MART-1-specific CD8 T-cell responses were significantly associated with IMP321 (Pâ<â0.02). At the peak of the response, MART-1-specific CD8 T cells contained higher proportions of effector (CCR7â» CD45RAâș/â») cells in the IMP321 group (Pâ<â0.02) and showed no sign of exhaustion (i.e. were mostly PD1â»CD160â»TIM3â»LAG3â»2B4âș/â»). Moreover, IMP321 was associated with a significantly reduced expansion of regulatory T cells (Pâ<â0.04); consistently, we observed a negative correlation between the relative expansion of MART-1-specific CD8 T cells and of regulatory T cells. Finally, although there were no confirmed responses as per RECIST criteria, a transient, 30-day partial response was observed in a patient from the IMP321 group.
CONCLUSIONS: Vaccination with IMP321 as an adjuvant in combination with lymphodepleting chemotherapy and adoptive transfer of autologous PBMCs induced more robust and durable cellular antitumor immune responses, supporting further development of IMP321 as an adjuvant for future immunotherapeutic strategies
Vaccination of stage III/IV melanoma patients with long NY-ESO-1 peptide and CpG-B elicits robust CD8(+) and CD4(+) T-cell responses with multiple specificities including a novel DR7-restricted epitope.
Long synthetic peptides and CpG-containing oligodeoxynucleotides are promising components for cancer vaccines. In this phase I trial, 19 patients received a mean of 8 (range 1-12) monthly vaccines s.c. composed of the long synthetic NY-ESO-179-108 peptide and CpG-B (PF-3512676), emulsified in Montanide ISA-51. In 18/18 evaluable patients, vaccination induced antigen-specific CD8(+) and CD4(+) T-cell and antibody responses, starting early after initiation of immunotherapy and lasting at least one year. The T-cells responded antigen-specifically, with strong secretion of IFNγ and TNFα, irrespective of patients' HLAs. The most immunogenic regions of the vaccine peptide were NY-ESO-189-102 for CD8(+) and NY-ESO-183-99 for CD4(+) T-cells. We discovered a novel and highly immunogenic epitope (HLA-DR7/NY-ESO-187-99); 7/7 HLA-DR7(+) patients generated strong CD4(+) T-cell responses, as detected directly ex vivo with fluorescent multimers. Thus, vaccination with the long synthetic NY-ESO-179-108 peptide combined with the strong immune adjuvant CpG-B induced integrated, robust and functional CD8(+) and CD4(+) T-cell responses in melanoma patients, supporting the further development of this immunotherapeutic approach
IGR J17354-3255 as a candidate intermediate SFXT possibly associated with the transient MeV AGL J1734-3310
We present spectral and temporal results from INTEGRAL long-term monitoring
of the unidentified X-ray source IGR J17354-3255. We show that it is a weak
persistent hard X-ray source spending a major fraction of the time in an
out-of-outburst state with average 18-60 keV X-ray flux of about 1.1 mCrab,
occasionally interspersed with fast X-ray flares (duration from a few hours to
a few days) with a dynamic range as high as 200. From archival Swift/XRT
observations, we also show that the dynamic range from non-detection to highest
level of measured X-ray activity is >300. Our IBIS timing analysis strongly
confirms the 8.4 days orbital period previously detected with Swift/BAT, in
addition we show that the shape of the orbital profile is rather smooth and
appears to be dominated by low level X-ray emission rather than by bright
outbursts, the measured degree of outburst recurrence is about 25 per cent. The
spectral and temporal characteristics of IGR J17354-3255 are highly indicative
of a Supergiant High Mass X-ray Binary nature (SGXB). However, our inferred
dynamic ranges both at soft and hard X-rays are significantly greater than
those of classical SGXB systems, but instead are typical of intermediate
Supergiant Fast X-ray Transient (SFXTs). Finally, we note for the first time
that the observed fast flaring X-ray behaviour of IGR J17354-3255 is very
similar to that detected with AGILE from the spatially associated MeV source
AGL J1734-3310, suggesting a possible physical link between the two objects.Comment: accepted for publication in MNRAS, 8 pages, 9 figures, 1 tabl
Cytolytic T-cell response against Epstein-Barr virus in lung cancer patients and healthy subjects
<p>Abstract</p> <p>Background</p> <p>This study aimed to examine whether EBV seropositive patients with lung cancer have an altered virus-specific CTL response, as compared to age-matched healthy controls and whether any variation in this response could be attributed to senescence.</p> <p>Methods</p> <p>Peripheral blood mononuclear cells from lung cancer patients, age-matched and younger healthy individuals were used to measure EBV-specific CTLs after in vitro amplification with the GLCTLVAML and RYSIFFDYM peptides followed by HLA-multimer staining.</p> <p>Results</p> <p>Lung cancer patients and aged-matched controls had significantly lesser EBV-specific CTL than younger healthy individuals. Multimer positive populations from either group did not differ with respect to the percentage of multimer positive CTLs and the intensity of multimer binding.</p> <p>Conclusions</p> <p>This study provides evidence that patients with lung cancer exhibit an EBV-specific CTL response equivalent to that of age-matched healthy counterparts. These data warrant the examination of whether young individuals have a more robust anti-tumor response, as is the case with the anti-EBV response.</p
Demonstrating the reliability of in vivo metabolomics based chemical grouping:towards best practice
While grouping/read-across is widely used to fill data gaps, chemical registration dossiers are often rejected due to weak category justifications based on structural similarity only. Metabolomics provides a route to robust chemical categories via evidence of shared molecular effects across source and target substances. To gain international acceptance, this approach must demonstrate high reliability, and best-practice guidance is required. The MetAbolomics ring Trial for CHemical groupING (MATCHING), comprising six industrial, government and academic ring-trial partners, evaluated inter-laboratory reproducibility and worked towards best-practice. An independent team selected eight substances (WY-14643, 4-chloro-3-nitroaniline, 17α-methyl-testosterone, trenbolone, aniline, dichlorprop-p, 2-chloroaniline, fenofibrate); ring-trial partners were blinded to their identities and modes-of-action. Plasma samples were derived from 28-day rat tests (two doses per substance), aliquoted, and distributed to partners. Each partner applied their preferred liquid chromatographyâmass spectrometry (LCâMS) metabolomics workflows to acquire, process, quality assess, statistically analyze and report their grouping results to the European Chemicals Agency, to ensure the blinding conditions of the ring trial. Five of six partners, whose metabolomics datasets passed quality control, correctly identified the grouping of eight test substances into three categories, for both male and female rats. Strikingly, this was achieved even though a range of metabolomics approaches were used. Through assessing intrastudy quality-control samples, the sixth partner observed high technical variation and was unable to group the substances. By comparing workflows, we conclude that some heterogeneity in metabolomics methods is not detrimental to consistent grouping, and that assessing data quality prior to grouping is essential. We recommend development of international guidance for quality-control acceptance criteria. This study demonstrates the reliability of metabolomics for chemical grouping and works towards best-practice
Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.
OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age
Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV
A search for new physics is presented based on an event signature of at least
three jets accompanied by large missing transverse momentum, using a data
sample corresponding to an integrated luminosity of 36 inverse picobarns
collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector
at the LHC. No excess of events is observed above the expected standard model
backgrounds, which are all estimated from the data. Exclusion limits are
presented for the constrained minimal supersymmetric extension of the standard
model. Cross section limits are also presented using simplified models with new
particles decaying to an undetected particle and one or two jets
Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV
A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay
channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7
TeV is presented. The data were collected at the LHC, with the CMS detector,
and correspond to an integrated luminosity of 4.6 inverse femtobarns. No
significant excess is observed above the background expectation, and upper
limits are set on the Higgs boson production cross section. The presence of the
standard model Higgs boson with a mass in the 270-440 GeV range is excluded at
95% confidence level.Comment: Submitted to JHE
Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC
Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H âÎł Îł, H â Z Zâ â4l and H âW Wâ âlÎœlÎœ. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of âs = 7 TeV and âs = 8 TeV, corresponding to an integrated luminosity of about 25 fbâ1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined ïŹts probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson
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