HIV infection induces phenotypic and functional changes to CD8+ T cells defined by the coordinated upregulation of a series of negative checkpoint receptors that eventually result in T cell ...exhaustion and failure to control viral replication. We report that effector CD8+ T cells during HIV infection in blood and SIV infection in lymphoid tissue exhibit higher levels of the negative checkpoint receptor TIGIT. Increased frequencies of TIGIT+ and TIGIT+ PD-1+ CD8+ T cells correlated with parameters of HIV and SIV disease progression. TIGIT remained elevated despite viral suppression in those with either pharmacological antiretroviral control or immunologically in elite controllers. HIV and SIV-specific CD8+ T cells were dysfunctional and expressed high levels of TIGIT and PD-1. Ex-vivo single or combinational antibody blockade of TIGIT and/or PD-L1 restored viral-specific CD8+ T cell effector responses. The frequency of TIGIT+ CD4+ T cells correlated with the CD4+ T cell total HIV DNA. These findings identify TIGIT as a novel marker of dysfunctional HIV-specific T cells and suggest TIGIT along with other checkpoint receptors may be novel curative HIV targets to reverse T cell exhaustion.
The ongoing severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) pandemic has a drastic impact on national health care systems. Given the overwhelming demand on facility capacity, the impact ...on all health care sectors has to be addressed. Solid organ transplantation represents a field with a high demand on staff, intensive care units, and follow‐up facilities. The great therapeutic value of organ transplantation has to be weighed against mandatory constraints of health care capacities. In addition, the management of immunosuppressed recipients has to be reassessed during the ongoing coronavirus disease 2019 (COVID‐19) pandemic. In addressing these crucial questions, transplant physicians are facing a total lack of scientific evidence. Therefore, the aim of this study was to offer an approach of consensus‐based guidance, derived from individual information of 22 transplant societies. Key recommendations were extracted and the degree of consensus among different organizations was calculated. A high degree of consensus was found for temporarily suspending nonurgent transplant procedures and living donation programs. Systematic polymerase chain reaction‐based testing of donors and recipients was broadly recommended. Additionally, more specific aspects (eg, screening of surgical explant teams and restricted use of marginal donor organs) were included in our analysis. This study offers a novel approach to informed guidance for health care management when a priori no scientific evidence is available.
This study summarizes recommendations of international societies on the management of transplant patients during the SARS‐CoV‐2 pandemic.
Purpose
Clinicians use tamsulosin, an α1‐adrenoceptor antagonist, to manage symptomatic benign prostatic hyperplasia (BPH). Because α1‐adrenoceptors are also present in the brain, the potential ...exists for adverse effects on cognitive functions. We explored the association between tamsulosin use and dementia risk.
Methods
We used Medicare data (2006–2012) to conduct a cohort study among patients aged ≥65 years and diagnosed with BPH. Men taking tamsulosin (n = 253 136) were matched at a 1:1 ratio using propensity‐scores to each of 6 comparison cohorts: patients who used no BPH‐medication (n = 180 926), and patients who used the following alternative‐BPH‐medications: doxazosin (n = 28 581), terazosin (n = 23 858), alfuzosin (n = 17 934), dutasteride (n = 34 027), and finasteride (n = 38 767). Assessment began following the first fill of BPH‐medication to identify incident dementia by ICD‐9 diagnosis codes. We estimated hazard ratios (HR) and 95% confidence intervals (CI) for dementia using Cox proportional hazard regression for each of the 6 propensity‐score‐matched cohort‐pairs.
Results
The median follow‐up period for all cohorts was 19.8 months. After propensity‐score matching, the tamsulosin cohort had an incidence of dementia of 31.3/1000 person‐years compared with only 25.9/1000 person‐years in the no‐BPH‐medication cohort. The risk of dementia was significantly higher in the tamsulosin cohort, when compared with the no‐BPH‐medication cohort (HR 95% CI: 1.17 1.14, 1.21) and each of the alternative‐BPH‐medication cohorts: doxazosin (1.20 1.12, 1.28), terazosin (1.11 1.04, 1.19), alfuzosin (1.12 1.03, 1.22), dutasteride (1.26 1.19, 1.34), and finasteride (1.13 1.07, 1.19). The significance of these findings persisted in sensitivity analyses.
Conclusion
Tamsulosin may increase the risk of dementia in older men with BPH.
Abstract Background The food environment shapes individual diets, and as food options change, energy and sodium intake may also shift. Understanding whether and how restaurant menus evolve in ...response to labeling laws and public health pressures could inform future efforts to improve the food environment. Objectives To track changes in the energy and sodium content of US chain restaurant main entrées between spring 2010 (when the Affordable Care Act was passed, which included a federal menu labeling requirement) and spring 2011. Design Nutrition information was collected from top US chain restaurants' websites, comprising 213 unique brands. Descriptive statistics and regression analysis evaluated change across main entrées overall and compared entrées that were added, removed, and unchanged. Tests of means and proportions were conducted for individual restaurant brands to see how many made significant changes. Separate analyses were conducted for children's menus. Results Mean energy and sodium did not change significantly overall, although mean sodium was 70 mg lower across all restaurants in added vs removed menu items at the 75th percentile. Changes were specific to restaurant brands or service model: family-style restaurants reduced sodium among higher-sodium entrées at the 75th percentile, but not on average, and entrées still far exceeded recommended limits. Fast-food restaurants decreased mean energy in children's menu entrées by 40 kcal. A few individual restaurant brands made significant changes in energy or sodium, but the vast majority did not, and not all changes were in the healthier direction. Among those brands that did change, there were slightly more brands that reduced energy and sodium compared with those that increased it. Conclusions Industry marketing and pledges may create a misleading perception that restaurant menus are becoming substantially healthier, but both healthy and unhealthy menu changes can occur simultaneously. Our study found no meaningful changes overall across a 1-year time period. Longer-term studies are needed to track changes over time, particularly after the federal menu labeling law is implemented.
The present study aimed to (i) describe the availability of nutrition information in major chain restaurants, (ii) document the energy and nutrient levels of menu items, (iii) evaluate relationships ...with restaurant characteristics, menu labelling and trans fat laws, and nutrition information accessibility, and (iv) compare energy and nutrient levels against industry-sponsored and government-issued nutrition criteria.
Descriptive statistics and multivariate regression analysis of the energy, total fat, saturated fat, trans fat, sodium, carbohydrate and protein levels of 29 531 regular and 1392 children's menu items corrected.
Energy and nutrition information provided on restaurant websites or upon request, and secondary databases on restaurant characteristics.
The top 400 US chain restaurants by sales, based on the 2009 list of the Restaurants & Institutions magazine.
Complete nutrition information was reported for 245 (61 %) restaurants. Appetizers had more energy, fat and sodium than all other item types. Children's menu specialty beverages had more fat, saturated fat and carbohydrates than comparable regular menu beverages. The majority of main entrées fell below one-third of the US Department of Agriculture's estimated daily energy needs, but as few as 3 % were also within limits for sodium, fat and saturated fat. Main entrées had significantly more energy, fat and saturated fat in family-style restaurants than in fast-food restaurants. Restaurants that made nutrition information easily accessible on websites had significantly lower energy, fat and sodium contents across menu offerings than those providing information only upon request.
The paper provides a comprehensive view of chain restaurant menu nutrition prior to nationwide labelling laws. It offers baseline data to evaluate how restaurants respond after laws are implemented.
Despite the success of antiretroviral therapy (ART) to halt viral replication and slow disease progression, this treatment is not curative and there remains an urgent need to develop approaches to ...clear the latent HIV reservoir. The human IL-15 superagonist N-803 (formerly ALT-803) is a promising anti-cancer biologic with potent immunostimulatory properties that has been extended into the field of HIV as a potential "shock and kill" therapeutic for HIV cure. However, the ability of N-803 to reactivate latent virus and modulate anti-viral immunity in vivo under the cover of ART remains undefined. Here, we show that in ART-suppressed, simian-human immunodeficiency virus (SHIV)SF162P3-infected rhesus macaques, subcutaneous administration of N-803 activates and mobilizes both NK cells and SHIV-specific CD8+ T cells from the peripheral blood to lymph node B cell follicles, a sanctuary site for latent virus that normally excludes such effector cells. We observed minimal activation of memory CD4+ T cells and no increase in viral RNA content in lymph node resident CD4+ T cells post N-803 administration. Accordingly, we found no difference in the number or magnitude of plasma viremia timepoints between treated and untreated animals during the N-803 administration period, and no difference in the size of the viral DNA cell-associated reservoir post N-803 treatment. These results substantiate N-803 as a potent immunotherapeutic candidate capable of activating and directing effector CD8+ T and NK cells to the B cell follicle during full ART suppression, and suggest N-803 must be paired with a bona fide latency reversing agent in vivo to facilitate immune-mediated modulation of the latent viral reservoir.
Chemically inducible dimerization (CID) uses a small molecule to induce binding of two different proteins. CID tools such as the FK506-binding protein-FKBP-rapamycin-binding- (FKBP-FRB)-rapamycin ...system have been widely used to probe molecular events inside and outside cells. While various CID tools are available, chemically inducible trimerization (CIT) does not exist, due to inherent challenges in designing a chemical that simultaneously binds three proteins with high affinity and specificity. Here, we developed CIT by rationally splitting FRB and FKBP. Cellular and structural datasets showed efficient trimerization of split pairs of FRB or FKBP with full-length FKBP or FRB, respectively, by rapamycin. CIT rapidly induced tri-organellar junctions and perturbed intended membrane lipids exclusively at select membrane contact sites. By conferring one additional condition to what is achievable with CID, CIT expands the types of manipulation in single live cells to address cell biology questions otherwise intractable and engineer cell functions for future synthetic biology applications.
Abstract
Molecular switches that respond to a biochemical stimulus in cells have proven utility as a foundation for developing molecular sensors and actuators that could be used to address important ...biological questions. Developing a molecular switch unfortunately remains difficult as it requires elaborate coordination of sensing and actuation mechanisms built into a single molecule. Here, we rationally designed a molecular switch that changes its subcellular localization in response to an intended stimulus such as an activator of protein kinase A (PKA). By arranging the sequence for Kemptide in tandem, we designed a farnesylated peptide whose localization can dramatically change upon phosphorylation by PKA. After testing a different valence number of Kemptide as well as modulating the linker sequence connecting them, we identified an efficient peptide switch that exhibited dynamic translocation between plasma membranes and internal endomembranes in a PKA activity dependent manner. Due to the modular design and small size, our PKA switch can have versatile utility in future studies as a platform for visualizing and perturbing signal transduction pathways, as well as for performing synthetic operations in cells.
Protein Kinase A (PKA) exists as a tetrameric holoenzyme which activates with increase of cAMP and plays an important role in many physiological processes including cardiac physiology, neuronal ...development, and adipocyte function. Although this kinase has been the subject of numerous biosensor designs, a single-fluorophore reporter that performs comparably to Förster resonance energy transfer (FRET) has not yet been reported. Here, we have used basic observations of electrostatic interactions in PKA substrate recognition mechanism and nucleus localization sequence motif to design a phosphorylation switch that shuttles between the cytosol and the nucleus, a strategy that should be generalizable to all basophilic kinases. The resulting reporter yielded comparable kinetics and dynamic range to the PKA FRET reporter, AKAR3EV. We also performed basic characterization and demonstrated its potential use in monitoring multiple signaling molecules inside cells using basic fluorescence microscopy. Due to the single-fluorophore nature of this reporter, we envision that this could find broad applications in studies involving single cell analysis of PKA activity.
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