Expansion of Human NK Cells Using K562 Cells Expressing OX40 Ligand and Short Exposure to IL-21

Background: Natural Killer (NK) cell-based immunotherapy used to treat cancer requires the adoptive transfer of a large number of activated NK cells. Here, we report a new effective method to expand human NK cells ex vivo using K562 cells genetically engineered (GE) to express OX40 ligand (K562-OX40L) in combination with a short exposure to soluble IL-21. In addition, we describe a possible mechanism of the NK cell expansion through the OX40 receptor-OX40 ligand axis which is dependent on NK cell homotypic interaction.Methods: K562-OX40L cells were generated by lentiviral transduction and were used as feeder cells to expand and activate NK cells from PBMCs in the presence of IL-2/IL-15. Soluble IL-21 was also added in various concentrations only once at the beginning of the culture. NK cells were expanded for 4–5 weeks, and the purity, expansion rate, phenotype and function (cytotoxicity, antibody-dependent cell-mediated cytotoxicity (ADCC), cytokine production, CD107a degranulation) of these expanded NK cells were compared to those generated by using K562 feeder cells.Results: The culture of NK cells with K562-OX40L cells in combination with the transient exposure to IL-21 highly enhanced NK cell expansion to approximately 2,000-fold after 4 weeks of culture, compared to a 303-fold expansion using the conventional K562 cells. Mechanistically, the OX40-OX40L axis between the feeder cells and NK cells as well as the homotypic interaction between NK cells through the OX40-OX40L axis were both necessary for NK cell expansion. The short exposure of NK cells to IL-21 had a synergistic effect with OX40 signaling for NK cell expansion. Apart from their enhanced expansion, NK cells grown with K562-OX40L feeder cells were similar to those grown with conventional K562 cells in regard to the surface expression of various receptors, cytotoxicity, ADCC, cytokine secretion, and CD107 degranulation.Conclusion: Our data suggest that OX40 ligand is a potent co-stimulant for the robust expansion of human NK cells and the homotypic NK cell interactions through the OX40-OX40L axis is a mechanism of NK cell expansion

Differentially Expressed Potassium Channels Are Associated with Function of Human Effector Memory CD8+T cells

The voltage-gated potassium channel, Kv1.3, and the Ca2+-activated potassium channel, KCa3.1, regulate membrane potentials in T cells, thereby controlling T cell activation and cytokine production. However, little is known about the expression and function of potassium channels in human effector memory ( EM) CD8+ T cells that can be further divided into functionally distinct subsets based on the expression of the interleukin ( IL)-7 receptor alpha ( IL-7R alpha) chain. Herein, we investigated the functional expression and roles of Kv1.3 and KCa3.1 in EM CD8+ T cells that express high or low levels of the IL-7 receptor alpha chain ( IL-7R alpha(high) and IL-7R alpha(low), respectively). In contrast to the significant activity of Kv1.3 and KCa3.1 in IL-7Rahigh EM CD8+ T cells, IL-7Ralow EM CD8+ T cells showed lower expression of Kv1.3 and insignificant expression of KCa3.1. Kv1.3 was involved in the modulation of cell proliferation and IL-2 production, whereas KCa3.1 affected the motility of EM CD8+ T cells. The lower motility of IL-7Ralow EM CD8+ T cells was demonstrated using transendothelial migration and motility assays with intercellular adhesion molecule 1-and/or chemokine stromal cell-derived factor-1 alpha-coated surfaces. Consistent with the lower migration property, IL-7Ralow EM CD8+ T cells were found less frequently in human skin. Stimulating IL-7Ralow EM CD8+ T cells with IL-2 or IL-15 increased their motility and recovery of KCa3.1 activity. Our findings demonstrate that Kv1.3 and KCa3.1 are differentially involved in the functions of EM CD8+ T cells. The weak expression of potassium channels in IL-7Ralow EM CD8+ T cells can be revived by stimulation with IL-2 or IL-15, which restores the associated functions. This study suggests that IL-7Rahigh EM CD8+ T cells with functional potassium channels may serve as a reservoir for effector CD8+ T cells during peripheral inflammation.112Ysciescopu

Rational Design of Semiconductor Heterostructures for Energy Conversion

Increasing worldwide energy consumption has imposed strain on natural energy sources and given rise to an energy crisis on our society. The development of efficient solar energy conversion to augment other renewable energy approaches is one of the grand challenges in our time. Water splitting, or the disproportionation of Hv2O into energy‐dense fuels, Hv2 and Ov2, is undoubtedly a promising strategy. However, solar water splitting has been a long challenge in the scientific community since the process involves the concerted transfer of four electrons and four protons, which requires the synergistic operation of solar light harvesting, charge separation, mass and charge transport, and redox catalysis processes. In the first thrust, we explore the development of tunable and programmable heterostructures comprised of MvxVv2Ov5 nanowires (where M = Pb^2+, Sn^2+) and cadmium chalogenide quantum dots (QDs: CdS, CdSe, and CdTe) designed to extract photoexcited holes from the valence band of quantum dot to mid-gap state of MvxVv2Ov5 nanowires to facilitate water oxidation at low overpotentials. Thermodynamic energetic band offsets and the relative band alignment of MxV2O5/QD heterostructures have been studied by hard X-ray photoelectron spectroscopy and density functional theory, whereas the dynamics of charge transfer kinetics has been examined by ultrafast transient absorption spectroscopy. These heterostructures demonstrate the remarkable utility of stereoactive lone pairs of post-transition-metal (p-block) cations in mediating solar energy conversion by dint of precise tunability of their energy positioning. In the second thrust, we develop an alternative palette of light harvesting semiconductors through the establishment of dimensional control over lead halide perovskites. The nucleation and growth processes are finely tuned with the help of added surface ligands in order to precisely control size and thus optical properties of the nanocrystals. Dimensional control is a key to engineering optical, electronic, and magnetic properties of materials owing to quantum confinement effects, selective elimination of symmetry elements, and the pronounced role of surface energy. Utilizing ligand-mediated synthetic approaches, such as ligand-assisted reprecipitation and hot colloidal methods, allows for control over nucleation/growth kinetics and consequently enables precise modulation of nanocrystal dimensions. In this dissertation, we have been successful at synthesizing precisely tunable 2D methylammonium lead bromide (MAPbBr3) nanoplatelets by controlling the surface-capping ligands. Utilizing a variety of spectroscopic tools, we have derived mechanistic understanding and structure— function correlations of the role of surface-capping ligands in mediating the growth of all-inorganic 2D CvsPbBrv3 nanoplatelets as a function of reaction temperature and concentration

Dataset of enhanced UV-C emitting properties of Pr3+-activated rare earth phosphates driven by structural lattice distortion through a substitutional doping strategy

Ongoing global pandemic crisis of coronavirus (COVID-19) and its fast- and wide-spreading into entire worlds, critically intimidating our current and future lives, put more emphasis on the development of efficient UV-C emitting phosphors for the germicidal and medical applications due to the intense UV-C emission, which can effectively deactivate such viruses. In this regard, UV-C emitting Pr3+-activated three presentative rare earth phosphate such as YPO4, LaPO4, and La (x mol.%, x =0-0.21)-doped YPO4 have been systematically investigated in terms of crystallographic evolution and their impact on the UV-C emitting properties. Scanning electron microscopy (SEM) images along with X-ray diffraction (XRD) patterns attested the substitutional doping of La into YPO4 host matrices. Optical properties mainly investigated using the photoluminescence (PL) emission spectroscopy in the spectral range from 220-300 nm corresponding to UV-C energy region clearly demonstrated that the substitutional doping of La into YPO4:Pr3+ leads to the increase in transition probability of UV-C emission, resulted from the electronic transition of activator corresponding to [Xe]4f15d1→[Xe]4f2. The data presented here are related to the research article entitled “Structural distortion induced enhancement in UV-C emitting properties of Pr3+-activated La-substituted yttrium phosphates (Y1-xLaxPO4:Pr3+)”

Effect of Coaching on Laparoscopic Surgical Task Performance in Laparoscopic Trainees and Experts

From the Washington University Undergraduate Research Digest: WUURD, Volume 11, 2015-2016. Published by the Office of Undergraduate Research, Joy Zalis Kiefer Director of Undergraduate Research and Assistant Dean in the College of Arts & Sciences; Lindsey Paunovich, Editor; Kristin Sobotka, Editor; Jennifer Kohl. Mentor: Michael Awar

Assessing the clinical requirement of 2.5% phenylephrine for diagnostic pupil examination

Purpose: To evaluate whether the standard dilating drop regimen consisting of phenylephrine, tropicamide, and proparacaine produces clinically significant improvement in pupil size compared to tropicamide and proparacaine during diagnostic eye examination. Methods: Sixty-three adult patients at Washington University School of Medicine Eye Clinic were enrolled in this prospective, randomized trial. Each patient received one of two dilating drop regimens: phenylephrine + tropicamide + proparacaine (PE+T+PP), which is considered the standard therapy, or tropicamide + proparacaine (T+PP). Main outcome measures were the proportion of pupils able to achieve successful clinical examination without need for additional dilating drops and change in predilation to postdilation pupil size. Comparisons were made using McNemar's test, repeated measures analysis of variance, and Fisher's test to determine whether PE is a necessary component of the standard eye examination. Results: There were no statistically significant differences between the PE+T+PP and T+PE treatment groups in predilation to postdilation changes in average resting pupil size (1.58 ± 0.66 and 2.61 ± 0.79; P = 0.57) or constricted pupil size (2.52 ± 0.93 and 3.56 ± 0.96; P = 0.15). There was no statistically significant difference between patients who obtained a successful dilated pupil examination between those receiving PE+T+PP and those receiving T+PP as determined by the examining physicians (Fisher's, P = 0.67). Conclusion: The addition of phenylephrine to tropicamide and proparacaine did not improve pupillary dilation size or ability to conduct a clinical examination. A single dilating agent using tropicamide should be considered in clinical practice

Fast-Response Colorimetric UVC Sensor Made of a Ga2O3 Photocatalyst with a Hole Scavenger

A fast-response colorimetric ultraviolet-C (UVC) sensor was demonstrated using a gallium oxide (Ga2O3) photocatalyst with small amounts of triethanolamine (TEOA) in methylene blue (MB) solutions and a conventional RGB photodetector. The color of the MB solution changed upon UVC exposure, which was observed using an in situ RGB photodetector. Thereby, the UVC exposure was numerically quantified as an MB reduction rate with the R value of the photodetector, which was linearly correlated with the measured spectral absorbance using a UV-Vis spectrophotometer. Small amount of TEOA in the MB solution served as a hole scavenger, which resulted in fast MB color changes due to the enhanced charge separation. However, excessive TEOA over 5 wt.% started to block the catalytical active site on the surface of Ga2O3, prohibiting the chemical reaction between the MB molecules and catalytic sites. The proposed colorimetric UVC sensor could monitor the detrimental UVC radiation with high responsivity at a low cost

Clinical Trends in Management of Locally Advanced ESCC: Real-World Evidence from a Large Single-Center Cohort Study

Neoadjuvant chemoradiation followed by surgery (NCRT+S) has been widely applied to patients with locally advanced esophageal squamous cell carcinoma (ESCC); however, treatment trends and their survival outcomes in a real-world clinical setting are poorly understood. This study aimed to analyze real-world evidence to understand treatment patterns and outcomes for patients with ESCC. We analyzed the treatment pattern and 5-year overall survival (5yOS) by synthesizing the individuals’ general characteristics, cancer information, and treatment records extracted from the Clinical Data Warehouse from 1994 to 2018. Of a total of 2151 patients, most patients received upfront surgery and 5yOS was 36.8% (31.4–43.1%). From 2003 to 2012, the use of NCRT increased, and 5yOS was improved to 42.2% (38.8–45.7%). Notably, after 2013, the proportion of NCRT+S markedly increased up to >50% of patients: 5yOS was much improved to 56.3% (53.2–59.6%). With regard to treatment, patients with NCRT+S had the most favorable 5yOS of 58.1% (53–63.7%), although that for patients with upfront surgery was 48.6% (45.9–51.5%, p < 0.001). Moreover, patients who received adjuvant therapy after surgery had better OS than those with surgery alone (58.4% (52.7–64.7%) vs. 47.3% (44.1–50.7%), p < 0.001). This analysis of real-world data demonstrated a significantly improved survival outcome for locally advanced ESCC over time since NCRT prior to surgery had been routinely applied. We revealed that NCRT+S was the most effective treatment for locally advanced ESCC and that adjuvant chemotherapy may be an encouraging therapeutic option for patients with positive nodes after upfront surgery