The microenvironment of head and neck squamous cell carcinomas (HNSCC) is highly immunosuppressive. HNSCCs expressing elevated levels of PD-L1 have especially poor outcome. Exosomes that carry PD-L1 ...and suppress T-cell functions have been isolated from plasma of patients with HNSCC. The potential contributions of PD-L1
exosomes to immune suppression and disease activity are evaluated.
Exosomes isolated from plasma of 40 HNSCC patients by size exclusion chromatography were captured on beads using anti-CD63 Abs, stained for PD-1 and PD-L1 and analyzed by flow cytometry. The percentages and mean fluorescence intensities (MFI) of PD-L1
and PD-1
exosome/bead complexes were correlated with the patients' clinicopathologic data. PD-L1
or PD-L1
exosomes were incubated with activated CD69
human CD8
T cells ± PD-1 inhibitor. Changes in CD69 expression levels on T cells were measured. Patients' plasma was tested for soluble PD-L1 (sPD-L1) by ELISA.
Levels of PD-L1 carried by exosomes correlated with patients' disease activity, the UICC stage and the lymph node status (
= 0.0008-0.013). In contrast, plasma levels of sPD-L1 or exosome PD-1 levels did not correlate with any clinicopathologic parameters. CD69 expression levels were inhibited (
< 0.03) by coincubation with PD-L1
but not by PD-L1
exosomes. Blocking of PD-L1
exosome signaling to PD-1
T cells attenuated immune suppression.
PD-L1 levels on exosomes, but not levels of sPD-L1, associated with disease progression in HNSCC patients. Circulating PD-L1
exosomes emerge as useful metrics of disease and immune activity in HNSCC patients.
Circulating PD-L1
exosomes in HNC patients' plasma but not soluble PD-L1 levels associate with disease progression.
.
Department of Biology, University of Copenhagen, Copenhagen, Denmark
The ability to control cell volume is pivotal for cell function. Cell volume perturbation elicits a wide array of signaling ...events, leading to protective (e.g., cytoskeletal rearrangement) and adaptive (e.g., altered expression of osmolyte transporters and heat shock proteins) measures and, in most cases, activation of volume regulatory osmolyte transport. After acute swelling, cell volume is regulated by the process of regulatory volume decrease (RVD), which involves the activation of KCl cotransport and of channels mediating K + , Cl – , and taurine efflux. Conversely, after acute shrinkage, cell volume is regulated by the process of regulatory volume increase (RVI), which is mediated primarily by Na + /H + exchange, Na + -K + -2Cl – cotransport, and Na + channels. Here, we review in detail the current knowledge regarding the molecular identity of these transport pathways and their regulation by, e.g., membrane deformation, ionic strength, Ca 2+ , protein kinases and phosphatases, cytoskeletal elements, GTP binding proteins, lipid mediators, and reactive oxygen species, upon changes in cell volume. We also discuss the nature of the upstream elements in volume sensing in vertebrate organisms. Importantly, cell volume impacts on a wide array of physiological processes, including transepithelial transport; cell migration, proliferation, and death; and changes in cell volume function as specific signals regulating these processes. A discussion of this issue concludes the review.
1 The classification of a given actin-associated protein as a regulator or a cytoskeletal protein per se is to some extent arbitrary. For the purpose of the present review, we have grouped myosin II, cortactin, and ERM proteins with the F-actin binding cytoskeletal proteins. However, obviously these proteins also impact profoundly on F-actin organization, and in this capacity, they will be discussed in section D2.
2 Where relevant, the regulation of specific transporters by the cytoskeleton is discussed in more detail in section VI and VII.
3 An additional gene product was assigned the name SLC9A11 ( http://www.gene.ucl.ac.uk/cgi-bin/nomenclature/ ), but is, to our knowledge, not yet proven to be a functional Na + /H + exchanger.
4 In the choroid plexus epithelium and brain microvascular endothelial cells, NKCC1 has been found to localize to the apical membrane (735, 819).
5 Alternatively spliced forms exist for both isoforms, yet will not be further discussed here (see Ref. 265).
Food allergy (FA) is an important atopic disease although its precise burden is unclear. This systematic review aimed to provide recent, up‐to‐date data on the incidence, prevalence, time trends, and ...risk and prognostic factors for FA in Europe. We searched four electronic databases, covering studies published from 1 January 2000 to 30 September 2012. Two independent reviewers appraised the studies and qualified the risk of bias using the Critical Appraisal Skills Programme tool. Seventy‐five eligible articles (comprising 56 primary studies) were included in a narrative synthesis, and 30 studies in a random‐effects meta‐analysis. Most of the studies were graded as at moderate risk of bias. The pooled lifetime and point prevalence of self‐reported FA were 17.3% (95% CI: 17.0–17.6) and 5.9% (95% CI: 5.7–6.1), respectively. The point prevalence of sensitization to ≥1 food as assessed by specific IgE was 10.1% (95% CI: 9.4–10.8) and skin prick test 2.7% (95% CI: 2.4–3.0), food challenge positivity 0.9% (95% CI: 0.8–1.1). While the incidence of FA appeared stable over time, there was some evidence that the prevalence may be increasing. There were no consistent risk or prognostic factors for the development or resolution of FA identified, but sex, age, country of residence, familial atopic history, and the presence of other allergic diseases seem to be important. Food allergy is a significant clinical problem in Europe. The evidence base in this area would benefit from additional studies using standardized, rigorous methodology; data are particularly required from Eastern and Southern Europe.
•New carbon isotope data capture the final stages of the Shuram/Wonoka excursion.•The transition to positive values postdates the appearance of calcified metazoans.•Anoxic ferruginous deeper waters ...were prevalent throughout this time.•Only mid-ramp settings were fully oxygenated.•Stability of oxygenation controlled the ecology of Ediacaran metazoan communities.
The first appearance of skeletal metazoans in the late Ediacaran (∼550 million years ago; Ma) has been linked to the widespread development of oxygenated oceanic conditions, but a precise spatial and temporal reconstruction of their evolution has not been resolved. Here we consider the evolution of ocean chemistry from ∼550 to ∼541Ma across shelf-to-basin transects in the Zaris and Witputs Sub-Basins of the Nama Group, Namibia. New carbon isotope data capture the final stages of the Shuram/Wonoka deep negative C-isotope excursion, and these are complemented with a reconstruction of water column redox dynamics utilising Fe–S–C systematics and the distribution of skeletal and soft-bodied metazoans. Combined, these inter-basinal datasets provide insight into the potential role of ocean redox chemistry during this pivotal interval of major biological innovation.
The strongly negative δ13C values in the lower parts of the sections reflect both a secular, global change in the C-isotopic composition of Ediacaran seawater, as well as the influence of ‘local’ basinal effects as shown by the most negative δ13C values occurring in the transition from distal to proximal ramp settings. Critical, though, is that the transition to positive δ13C values postdates the appearance of calcified metazoans, indicating that the onset of biomineralization did not occur under post-excursion conditions.
Significantly, we find that anoxic and ferruginous deeper water column conditions were prevalent during and after the transition to positive δ13C that marks the end of the Shuram/Wonoka excursion. Thus, if the C isotope trend reflects the transition to global-scale oxygenation in the aftermath of the oxidation of a large-scale, isotopically light organic carbon pool, it was not sufficient to fully oxygenate the deep ocean.
Both sub-basins reveal highly dynamic redox structures, where shallow, inner ramp settings experienced transient oxygenation. Anoxic conditions were caused either by episodic upwelling of deeper anoxic waters or higher rates of productivity. These settings supported short-lived and monospecific skeletal metazoan communities. By contrast, microbial (thrombolite) reefs, found in deeper inner- and mid-ramp settings, supported more biodiverse communities with complex ecologies and large skeletal metazoans. These long-lived reef communities, as well as Ediacaran soft-bodied biotas, are found particularly within transgressive systems, where oxygenation was persistent. We suggest that a mid-ramp position enabled physical ventilation mechanisms for shallow water column oxygenation to operate during flooding and transgressive sea-level rise. Our data support a prominent role for oxygen, and for stable oxygenated conditions in particular, in controlling both the distribution and ecology of Ediacaran skeletal metazoan communities.
We study the linear and non-linear bias parameters which determine the mapping between the distributions of galaxies and the full matter density fields, comparing different measurements and ...predictions. Associating galaxies with dark matter haloes in the Marenostrum Institut de Ciencies de l'Espai (MICE) Grand Challenge N-body simulation, we directly measure the bias parameters by comparing the smoothed density fluctuations of haloes and matter in the same region at different positions as a function of smoothing scale. Alternatively, we measure the bias parameters by matching the probability distributions of halo and matter density fluctuations, which can be applied to observations. These direct bias measurements are compared to corresponding measurements from two-point and different third-order correlations, as well as predictions from the peak-background model, which we presented in previous papers using the same data. We find an overall variation of the linear bias measurements and predictions of ~5 per cent with respect to results from two-point correlations for different halo samples with masses between ~10... and 10... h... M... at the redshifts z = 0.0 and 0.5. Variations between the second- and third-order bias parameters from the different methods show larger variations, but with consistent trends in mass and redshift. The various bias measurements reveal a tight relation between the linear and the quadratic bias parameters, which is consistent with results from the literature based on simulations with different cosmologies. Such a universal relation might improve constraints on cosmological models, derived from second-order clustering statistics at small scales or higher order clustering statistics. (ProQuest: ... denotes formulae/symbols omitted.)
Initiation, growth, recurrence, and metastasis of head and neck squamous cell carcinomas (HNSCC) have been related to the behavior of cancer stem cells (CSC) that can be identified by their ...aldehyde-dehydrogenase-isoform-1 (ALDH1) activity. We quantified and enriched ALDH1(+) cells within HNSCC cell lines and subsequently characterized their phenotypical and functional properties like invasion capacity and epithelial-mesenchymal transition (EMT). Spheroid culture enriched CSC from five HNSCC cell lines by up to 5-fold. In spheroid-derived cells (SDC) and the parental monolayer-derived cell line ALDH1, CD44, CD24, E-Cadherin, α-SMA, and Vimentin expression was compared by flow-cytometry and immunofluorescence together with proliferation and cell cycle analysis. Invasion activity was evaluated by Matrigel assay and expression of stemness-related transcription factors (TF) Nanog, Oct3/4, Sox2 and EMT-related genes Snail1 and 2, and Twist by real-time PCR. All cell lines formed spheroids that could self-renew and be serially re-passaged. ALDH1 expression was significantly higher in SDC. ALDH1(+) cells showed increased colony-formation. The proportion of cells with a putative CSC marker constellation of CD44(+)/CD24(-) was highly variable (0.5% to 96%) in monolayer and spheroid cultures and overlapped in 0%-33% with the CD44(+)/CD24(-)/ALDH1(+) cell subset. SDC had significantly higher invading activity. mRNA of the stemness-related genes Sox2, Nanog, and Oct3/4 was significantly increased in SDC of all cell lines. Twist was significantly increased in two while Snail2 showed a significant increase in one and a significant decrease in SDC of two cell lines. SDC had a higher G0 phase proportion, showed high-level expression of α-SMA and Vimentin, but significantly decreased E-Cadherin expression. HNSCC-lines harbor potential CSC, characterized by ALDH1 and stemness marker TF expression as well as properties like invasiveness, quiescence, and EMT. CSC can be enriched by anchorage-independent culture techniques, which may be important for the investigation of their contribution to therapy resistance, tumor recurrence and metastasis.
Surgical removal of the larynx (total laryngectomy) offers a curative approach to patients with advanced laryngeal and hypopharyngeal (squamous cell) cancer without distant metastases. Particularly ...in T4a carcinoma, laryngectomy seems prognostically superior to primary radio(chemo)therapy. Further relevant indications for laryngectomy include massive laryngeal dysfunction associated with aspiration and recurrence after radio(chemo)therapy, resulting in salvage surgery. The surgical procedure including neck dissection is highly standardised and safe. The resulting aphonia can be compensated by functional rehabilitation (e.g., voice prosthesis) associated with a significant quality of life improvement. This article presents an overview of indications, preoperative diagnostics, surgical procedures, including new developments (robotics), possible complications, the choice of adjuvant treatment, alternative therapeutic approaches, rehabilitation and prognosis. In summary, total laryngectomy still represents a relevant surgical procedure in modern head and neck oncology.
The efficacy of deep brain stimulation in treating movement disorders depends critically on electrode localization, which is conventionally described by using coordinates relative to the ...midcommissural point. This approach requires manual measurement and lacks spatial normalization of anatomic variances. Normalization is based on intersubject spatial alignment (coregistration) of corresponding brain structures by using different geometric transformations. Here, we have devised and evaluated a scheme for automated subcortical optimization of coregistration (ASOC), which maximizes patient-to-atlas normalization accuracy of postoperative structural MR imaging into the standard Montreal Neurologic Institute (MNI) space for the basal ganglia.
Postoperative T2-weighted MR imaging data from 39 patients with Parkinson disease and 32 patients with dystonia were globally normalized, representing the standard registration (control). The global transformations were regionally refined by 2 successive linear registration stages (RSs) (ASOC-1 and 2), focusing progressively on the basal ganglia with 2 anatomically selective brain masks, which specify the reference volume (weighted cost function). Accuracy of the RSs was quantified by spatial dispersion of 16 anatomic landmarks and their root-mean-square errors (RMSEs) with respect to predefined MNI-based reference points. The effects of CSF volume, age, and sex on RMSEs were calculated.
Mean RMSEs differed significantly (P < .001) between the global control (4.2 +/- 2.0 mm), ASOC-1 (1.92 +/- 1.02 mm), and ASOC-2 (1.29 +/- 0.78 mm).
The present method improves the registration accuracy of postoperative structural MR imaging data into MNI space within the basal ganglia, allowing automated normalization with increased precision at stereotactic targets, and enables lead-contact localization in MNI coordinates for quantitative group analysis.
In patients with ulcerative colitis (UC), alterations of the intestinal microbiota, termed dysbiosis, have been postulated to contribute to intestinal inflammation. Fecal microbiota transplantation ...(FMT) has been used as effective therapy for recurrent Clostridium difficile colitis also caused by dysbiosis. The aims of the present study were to investigate if patients with UC benefit from FMT and if dysbiosis can be reversed.
Six patients with chronic active UC nonresponsive to standard medical therapy were treated with FMT by colonoscopic administration. Changes in the colonic microbiota were assessed by 16S rDNA-based microbial community profiling using high-throughput pyrosequencing from mucosal and stool samples.
All patients experienced short-term clinical improvement within the first 2 weeks after FMT. However, none of the patients achieved clinical remission. Microbiota profiling showed differences in the modification of the intestinal microbiota between individual patients after FMT. In 3 patients, the colonic microbiota changed toward the donor microbiota; however, this did not correlate with clinical response. On phylum level, there was a significant reduction of Proteobacteria and an increase in Bacteroidetes after FMT.
FMT by a single colonoscopic donor stool application is not effective in inducing remission in chronic active therapy-refractory UC. Changes in the composition of the intestinal microbiota were significant and resulted in a partial improvement of UC-associated dysbiosis. The results suggest that dysbiosis in UC is at least in part a secondary phenomenon induced by inflammation and diarrhea rather than being causative for inflammation in this disease.
Purpose
In recent years Magnetic Resonance Elastography (MRE) emerged into a clinically applicable imaging technique. It has been shown that MRE is capable of measuring global changes of the ...viscoelastic properties of cerebral tissue. The purpose of our study was to evaluate a spatially resolved three-dimensional multi-frequent MRE (3DMMRE) for assessment of the viscoelastic properties of intracranial tumours.
Methods
A total of 27 patients (63±13 years) were included. All examinations were performed on a 3.0 T scanner, using a modified phase-contrast echo planar imaging sequence. We used 7 vibration frequencies in the low acoustic range with a temporal resolution of 8 dynamics per wave cycle. Post-processing included multi-frequency dual elasto-visco (MDEV) inversion to generate high-resolution maps of the magnitude |
G
*| and the phase angle φ of the complex valued shear modulus.
Results
The tumour entities included in this study were: glioblastoma (
n
= 11), anaplastic astrocytoma (
n
= 3), meningioma (
n
= 7), cerebral metastasis (
n
= 5) and intracerebral abscess formation (
n
= 1). Primary brain tumours and cerebral metastases were not distinguishable in terms of |
G
*| and φ. Glioblastoma presented the largest range of |
G
*| values and a trend was delineable that glioblastoma were slightly softer than WHO grade III tumours. In terms of φ, meningiomas were clearly distinguishable from all other entities.
Conclusions
In this pilot study, while analysing the viscoelastic constants of various intracranial tumour entities with an improved spatial resolution, it was possible to characterize intracranial tumours by their mechanical properties. We were able to clearly delineate meningiomas from intraaxial tumours, while for the latter group an overlap remains in viscoelastic terms.
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