Analysis of multifunctional CD4
T cells is fundamental for characterizing the immune responses to vaccination or infection. Major histocompatibility complex (MHC)/peptide tetramers represent a ...powerful technology for the detection of antigen-specific T cells by specific binding to their T-cell receptor, and their combination with functional assays is fundamental for characterizing the antigen-specific immune response. Here we optimized a protocol for the detection of multiple intracellular cytokines within epitope-specific CD4
T cells identified by the MHC class II tetramer technology. The optimal procedure for assessing the functional activity of tetramer-binding CD4
T cells was based on the simultaneous intracellular staining with both MHC tetramers and cytokine-specific antibodies upon
restimulation of cells with the vaccine antigen. The protocol was selected among procedures that differently combine the steps of cellular restimulation and tetramer staining with intracellular cytokine labeling. This method can be applied to better understand the complex functional profile of CD4
T-cell responses upon vaccination or infection.
The
in vitro
stimulation of immune system cells with live or killed bacteria is essential for understanding the host response to pathogens. In the present study, we propose a model combining ...transcriptomic and cytokine assays on murine splenocytes to describe the immune recall in the days following pneumococcal lung infection. Mice were sacrificed at days 1, 2, 4, and 7 after
Streptococcus pneumoniae
(TIGR4 serotype 4) intranasal infection and splenocytes were cultured in the presence or absence of the same inactivated bacterial strain to access the transcriptomic and cytokine profiles. The stimulation of splenocytes from infected mice led to a higher number of differentially expressed genes than the infection or stimulation alone, resulting in the enrichment of 40 unique blood transcription modules, including many pathways related to adaptive immunity and cytokines. Together with transcriptomic data, cytokines levels suggested the presence of a recall immune response promoting both innate and adaptive immunity, stronger from the fourth day after infection. Dimensionality reduction and feature selection identified key variables of this recall response and the genes associated with the increase in cytokine concentrations. This model could study the immune responses involved in pneumococcal infection and possibly monitor vaccine immune response and experimental therapies efficacy in future studies.
Post-kala-azar dermal leishmaniasis (PKDL) is a chronic, stigmatizing skin condition occurring frequently after apparent clinical cure from visceral leishmaniasis. Given an urgent need for new ...treatments, we conducted a phase IIa safety and immunogenicity trial of ChAd63-KH vaccine in Sudanese patients with persistent PKDL. LEISH2a (ClinicalTrials.gov: NCT02894008) was an open-label three-phase clinical trial involving sixteen adult and eight adolescent patients with persistent PKDL (median duration, 30 months; range, 6–180 months). Patients received a single intramuscular vaccination of 1 × 1010 viral particles (v.p.; adults only) or 7.5 × 1010 v.p. (adults and adolescents), with primary (safety) and secondary (clinical response and immunogenicity) endpoints evaluated over 42–120 days follow-up. AmBisome was provided to patients with significant remaining disease at their last visit. ChAd63-KH vaccine showed minimal adverse reactions in PKDL patients and induced potent innate and cell-mediated immune responses measured by whole-blood transcriptomics and ELISpot. 7/23 patients (30.4%) monitored to study completion showed >90% clinical improvement, and 5/23 (21.7%) showed partial improvement. A logistic regression model applied to blood transcriptomic data identified immune modules predictive of patients with >90% clinical improvement. A randomized controlled trial to determine whether these clinical responses were vaccine-related and whether ChAd63-KH vaccine has clinical utility is underway.
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Post-kala-azar dermal leishmaniasis (PKDL) is a chronic parasitic disease with limited treatment options. Here, Musa and colleagues report on a phase IIa therapeutic trial of the adenoviral-vectored leishmaniasis vaccine ChAd63-KH. Single-dose vaccination with ChAd63-KH was safe and induced innate and T cell responses in Sudanese patients with PKDL.
This paper presents the results of a systematic laboratory investigation on the static behavior of silica sand containing various amounts of either plastic or nonplastic fines. Specimens were ...reconstituted using a new technique suitable for element testing of homogeneous specimens of sands containing fines deposited in water (e.g., alluvial deposits, hydraulic fills, tailings dams, and offshore deposits). The fabric of sands containing fines was examined using the environmental scanning electron microscope (ESEM). Static, monotonic, isotropically consolidated, drained triaxial compression tests were performed to evaluate the stress-strain-volumetric response of these soils. Piezoceramic bender element instrumentation was developed and integrated into a conventional triaxial apparatus; shear-wave velocity measurements were made to evaluate the small-strain stiffness of the sands tested at various states. The intrinsic parameters that characterize critical state, dilatancy, and small-strain stiffness of clean, silty, and clayey sands were determined. All aspects of the mechanical behavior investigated in this study (e.g., stress-strain-volumetric response, shear strength, and small-strain stiffness) are affected by both the amount and plasticity of the fines present in the sand. Microstructural evaluation using the ESEM highlighted the importance of soil fabric on the overall soil response.
Gram-negative bacteremia (GNB) is a major cause of illness and death after hematopoietic stem cell transplantation (HSCT), and updated epidemiological investigation is advisable.
We prospectively ...evaluated the epidemiology of pre-engraftment GNB in 1118 allogeneic HSCTs (allo-HSCTs) and 1625 autologous HSCTs (auto-HSCTs) among 54 transplant centers during 2014 (SIGNB-GITMO-AMCLI study). Using logistic regression methods. we identified risk factors for GNB and evaluated the impact of GNB on the 4-month overall-survival after transplant.
The cumulative incidence of pre-engraftment GNB was 17.3% in allo-HSCT and 9% in auto-HSCT. Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa were the most common isolates. By multivariate analysis, variables associated with GNB were a diagnosis of acute leukemia, a transplant from a HLA-mismatched donor and from cord blood, older age, and duration of severe neutropenia in allo-HSCT, and a diagnosis of lymphoma, older age, and no antibacterial prophylaxis in auto-HSCT. A pretransplant infection by a resistant pathogen was significantly associated with an increased risk of posttransplant infection by the same microorganism in allo-HSCT. Colonization by resistant gram-negative bacteria was significantly associated with an increased rate of infection by the same pathogen in both transplant procedures. GNB was independently associated with increased mortality at 4 months both in allo-HSCT (hazard ratio, 2.13; 95% confidence interval, 1.45-3.13; P <.001) and auto-HSCT (2.43; 1.22-4.84; P = .01).
Pre-engraftment GNB is an independent factor associated with increased mortality rate at 4 months after auto-HSCT and allo-HSCT. Previous infectious history and colonization monitoring represent major indicators of GNB.
NCT02088840.
NGC 796 is a massive young cluster located 59 kpc from us in the diffuse intergalactic medium of the 1/5-1/10 Z☉ Magellanic Bridge, allowing us to probe variations in star formation and stellar ...evolution processes as a function of metallicity in a resolved fashion, and providing a link between resolved studies of nearby solar-metallicity and unresolved distant metal-poor clusters located in high-redshift galaxies. In this paper, we present adaptive optics griH imaging of NGC 796 (at 0 5, which is ∼0.14 pc at the cluster distance) along with optical spectroscopy of two bright members to quantify the cluster properties. Our aim is to explore whether star formation and stellar evolution vary as a function of metallicity by comparing the properties of NGC 796 to higher-metallicity clusters. We find an age of 20 − 5 + 12 Myr from isochronal fitting of the cluster main sequence in the color-magnitude diagram. Based on the cluster luminosity function, we derive a top-heavy stellar initial mass function (IMF) with a slope = 1.99 0.2, hinting at a metallicity and/or environmental dependence of the IMF, which may lead to a top-heavy IMF in the early universe. Study of the H emission-line stars reveals that classical Be stars constitute a higher fraction of the total B-type stars when compared with similar clusters at greater metallicity, providing some support to the chemically homogeneous theory of stellar evolution. Overall, NGC 796 has a total estimated mass of 990 200 M , and a core radius of 1.4 0.3 pc, which classifies it as a massive young open cluster, unique in the diffuse interstellar medium of the Magellanic Bridge.
Orthorexia nervosa (ON) is defined as the excessive attention on healthy eating, and studies especially focused on food quality ON prevalence in university students can be extremely variable. The ...objective of this study is to investigate whether there was a difference in ON risk between health-scientific, economic-humanistic, sport sciences and dietetics and nutrition students, and to evaluate if lifestyle-related ON risk factors (dieting, physical activity, drugs and supplements use) could have an impact in different ways in determining ON risk among students attending these four programs. Participants were recruited at the University of Pavia and received a two-section questionnaire including demographic and lifestyle information and the ORTO-15 questionnaire. A total of 671 students (54% F e 46% M) completed the questionnaire (median age 21.00 (IQR 20.00−23.00), median BMI 21.77 kg/m2 (IQR 20.06−23.66 kg/m2)). The 31.2% had ORTO-15 test scores < 35, and were considered at risk of having ON. No differences were found in ON risk among the students attending the four university courses. Dieting was confirmed as the major ON risk factor for health-scientific, economic-humanistic and sport sciences students. The type of sport practiced was an important determinant of ON risk only for the economic-humanistic course, while supplements use was statistically different between sport sciences students with or without ON. Our findings may suggest that lifestyle-related risk factors of orthorexia can differ among the students of distinct university courses, but these results need to be supported by further longitudinal and prospective studies.
Summary
Background
Understanding genetic variations is important in predicting treatment response and forms the basis for identifying new pharmacogenetic and pharmacogenomic targets for psoriasis ...treatment. There are limited data on the efficacy of secukinumab in relation to genetic markers.
Objectives
To evaluate the efficacy and safety of secukinumab 300 mg in HLA‐Cw6‐positive (Cw6‐POS) and HLA‐Cw6‐negative (Cw6‐NEG) patients with moderate‐to‐severe chronic plaque‐type psoriasis.
Methods
SUPREME was a 24‐week, phase IIIb study with an extension period up to 72 weeks. Primary end point was Psoriasis Area Severity Index (PASI) 90 response rate after 16 weeks.
Results
In total, 434 patients were recruited: 185 (42·6%) were Cw6‐POS and 246 (56·7%) were Cw6‐NEG (three not assessed). Mean ± SD age was 45·2 ± 13·2 years (Cw6‐POS 42·7 ± 13·1; Cw6‐NEG 47·2 ± 12·9). The baseline PASI score was comparable between the cohorts Cw6‐POS 20·7 ± 8·99; Cw6‐NEG 21·5 ± 9·99 (P = 0·777). At week 16, PASI 90 was achieved in 80·4% of Cw6‐POS and 79·7% of Cw6‐NEG patients (difference 0·76; 95% confidence interval −7·04 to 8·23). No differences in absolute PASI at week 16 (Cw6‐POS 1·36 ± 3·58; Cw6‐NEG 1·18 ± 2·29) were observed. The overall safety profile of secukinumab was consistent with that previously reported. No statistically significant difference was detected in the rate of treatment‐emergent adverse events Cw6‐POS 42·7%; Cw6‐NEG 49·6% (P = 0·295). A high PASI 90 response was achieved with secukinumab with a fast reduction in absolute PASI.
Conclusions
Determination of HLA‐Cw6 status for secukinumab therapy is unnecessary, as it is highly effective regardless of HLA‐Cw6 status.
What's already known about this topic?
HLA‐Cw6 is associated with the phenotypic features of psoriasis and positive response to ustekinumab and is present in approximately 40–80% of cases.
Secukinumab is a fully human monoclonal antibody neutralizing interleukin‐17A and it has demonstrated a rapid onset of action and sustained responses with a favourable safety profile in moderate‐to‐severe psoriasis, psoriatic arthritis and ankylosing spondylitis.
What does this study add?
Although HLA‐Cw6‐positive and HLA‐Cw6‐negative patients have distinct clinical features, the present study showed that secukinumab achieved similar clinical responses in both cohorts after 24 weeks of treatment.
There was no difference in efficacy regarding HLA‐Cw6 status.
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