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In order to adapt to the rapid development of green plant extract corrosion inhibitors, spinach extract (SPE) was selected as a corrosion inhibitor for Q235 steel in citric acid (CA) environment. SPE was extracted using a simple ethanol reflux method, and its main components, as well as their stability in CA, were confirmed through Fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible spectroscopy (UV-Vis). The corrosion inhibition performance of SPE on Q235 steel in 0.5 mol/L CA solution was investigated using various methods including weight loss, dynamic potential polarization (PDP), linear polarization resistance (LPR), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and contact angle measurements. Effects of temperature on the activation parameters (Ea, were studied by calculation. Results showed that chlorophyll was the main component of SPE, which exhibited good stability in a 0.5 mol/L CA solution. Furthermore, SPE significantly reduced the corrosion rate of Q235 steel in the 0.5 mol/L CA medium, acting as a mixed corrosion inhibitor for both cathodic and anodic reactions. With the increase of SPE concentration, both cathodic and anodic currents were reduced, active corrosion sites were blocked, the corrosion rate was decreased, and the corrosion inhibition efficiency was enhanced. The corrosion inhibition efficiency of Q235 steel obtained by weight loss method, PDP, LPR and EIS was more than 80% with 2.134 g/L of SPE concentration at 303 K. With the increase of system temperature, the corrosion inhibition efficiency of SPE on Q235 steel decreased, but the change was smaller. Compared to the blank system, the activation energy (Ea) of the system significantly increased after the addition of SPE. The effective components of SPE adsorped to the surface of Q235 steel in accordance with the Langmuir isotherm, predominantly through physical adsorption, and were characterized as monolayer adsorption. SPE exhibited good corrosion inhibition performance for Q235 steel in a 0.5 mol/L CA solution system, which was a green corrosion inhibitor with good application prospects in the pickling field. It could provide certain guidance for the development of plant extract-based corrosion inhibitors.

The key challenge in the manufacture of advanced high-temperature piezoceramic energy harvesters (HT-PEHs) with excellent electromechanical conversion capability is the development of piezoceramic materials with a large piezoelectric coefficient (d33) and a high depolarization temperature (Td). Herein, a (1 − x − y)BiScO3–xBiYbO3–yPbTiO3 ((1 − x − y)BS–xBY–yPT) ternary perovskite piezoelectric system with a Curie temperature of more than 425 °C is reported. The x/y = 0.01/0.61 ceramic at the morphotropic phase boundary (MPB) displays a large high-temperature d33 value of 665 pC N−1 and a high Td of 348 °C, which are far better than the corresponding values for many existing typical Pb(Zr, Ti)O3- and BS–PT-based perovskite piezoceramics. These remarkable high-temperature piezoelectric properties can be ascribed to vertical MPB and to the improved tetragonal phase structure with its thermally stable domains. Furthermore, the HT-PEH assembled using the 0.38BS–0.01BY–0.61PT MPB specimen demonstrates an excellent power generation capacity under harsh high-temperature conditions at 200–350 °C, and the converted electrical energy can light up commercial light-emitting diodes. The above results demonstrate that (1 − x − y)BS–xBY–yPT are highly competitive potential stock materials for the preparation of PEHs that are suitable for harsh high-temperature environments. [ABSTRACT FROM AUTHOR]

Neutralizing antibodies exert a potent inhibitory effect on viral entry; however, they are less effective in therapeutic models than in prophylactic models, presumably because of their limited efficacy in eliminating virus-producing cells via Fc-mediated cytotoxicity. Herein, we present a SARS-CoV-2 spike-targeting bispecific T-cell engager (S-BiTE) strategy for controlling SARS-CoV-2 infection. This approach blocks the entry of free virus into permissive cells by competing with membrane receptors and eliminates virus-infected cells via powerful T cell-mediated cytotoxicity. S-BiTE is effective against both the original and Delta variant of SARS-CoV2 with similar efficacy, suggesting its potential application against immune-escaping variants. In addition, in humanized mouse model with live SARS-COV-2 infection, S-BiTE treated mice showed significantly less viral load than neutralization only treated group. The S-BiTE strategy may have broad applications in combating other coronavirus infections. A SARS-CoV-2 spike-targeting bispecific T-cell engager (S-BiTE) strategy is presented that effectively reduces SARS-CoV-2 viral load in a humanized mouse model. [ABSTRACT FROM AUTHOR]

While chimeric antigen receptor-modified T (CAR-T) cells have shown great success for the treatment of B cell leukemia, their efficacy appears to be compromised in B cell derived lymphoma and solid tumors. Optimization of the CAR design to improve persistence and cytotoxicity is a focus of the current CAR-T study. Herein, we established a novel CAR structure by adding a full length 4-1BB co-stimulatory receptor to a 28Z-based second generation CAR that targets CD20. Our data indicated that this new 2028Z-4-1BB CAR-T cell showed improved proliferation and cytotoxic ability. To further understand the mechanism of action, we found that constitutive 4-1BB sensing significantly reduced the apoptosis of CAR-T cells, enhanced proliferation, and increased NF-κB pathway activation. Consistent with the enhanced proliferation and cytotoxicity in vitro , this new structure of CAR-T cells exhibited robust persistence and anti-tumor activity in a mouse xenograft lymphoma model. This work provides evidence for a new strategy to optimize the function of CAR-T against lymphoma. [ABSTRACT FROM AUTHOR]

Intuitive CD8+ T cells sense DNA: Stimulator of interferon genes (STING) agonism is an area of active exploration for cancer immunotherapy. Li et al. examined the cGAS-STING DNA sensing cascade in antitumor CD8+ T cells. They observed dampened STING activity in CD8+ T cells from patients with cancer or mice implanted with tumors. STING signaling supported a stem-like memory phenotype in the T cells, which is known to be beneficial for responses to immunotherapy. Cytosolic DNA was enriched in activated T cells, and STING agonism improved efficacy of adoptive cell therapy in multiple mouse models. These results highlight that CD8+ T cell DNA sensing could be exploited for therapeutic benefit in immunotherapy. Although cGAS-STING–mediated DNA sensing in tumor cells or phagocytes is central for launching antitumor immunity, the role of intrinsic cGAS-STING activation in T cells remains unknown. Here, we observed that peripheral blood CD8+ T cells from patients with cancer showed remarkably compromised expression of the cGAS-STING cascade. We demonstrated that the cGAS-STING cascade in adoptively transferred CD8+ T cells was essential for antitumor immune responses in the context of T cell therapy in mice. Mechanistically, cell-autonomous cGAS and STING promoted the maintenance of stem cell–like CD8+ T cells, in part, by regulating the transcription factor TCF1 expression. Moreover, autocrine cGAS-STING–mediated type I interferon signaling augmented stem cell–like CD8+ T cell differentiation program mainly by restraining Akt activity. In addition, genomic DNA was selectively enriched in the cytosol of mouse CD8+ T cells upon in vitro and in vivo stimulation. STING agonism enhanced the formation of stem-like central memory CD8+ T cells from patients with cancer and potentiated antitumor responses of CAR-T cell therapy in a xenograft model. These findings advance our understanding of inherent cGAS-STING activation in T cells and provide insight into the development of improved T cell therapy by harnessing the cGAS-STING pathway for cancer immunotherapy. [ABSTRACT FROM AUTHOR]

The emergence of the novel human severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to the pandemic of coronavirus disease 2019 (COVID-19), which has markedly affected global health and the economy. Both uncontrolled viral replication and a proinflammatory cytokine storm can cause severe tissue damage in patients with COVID-19. SARS-CoV-2 utilizes angiotensin-converting enzyme 2 (ACE2) as its entry receptor. In this study, we generated ACE2 extracellular domain-Fc and single-chain variable fragment-interleukin 6 (IL-6) single-chain variable fragment against IL-6 receptor (scFv-IL6R)-Fc fusion proteins to differentially neutralize viruses and ameliorate the cytokine storm. The human ACE2 (hACE2) 1-740 -Fc fusion protein showed a potent inhibitory effect on pseudo-typed SARS-CoV-2 entry and a good safety profile in mice. In addition, scFv-IL6R-Fc strongly blocked IL-6 signal activation. We also established a mesenchymal stromal cell (MSC)-based hACE2 1-740 -Fc and scFv-IL6R-Fc delivery system, which could serve as a potential therapy strategy for urgent clinical needs of patients with COVID-19., Competing Interests: The authors declare no competing interests., (© 2021 The Author(s).)

While chimeric antigen receptor-modified T (CAR-T) cells have shown great success for the treatment of B cell leukemia, their efficacy appears to be compromised in B cell derived lymphoma and solid tumors. Optimization of the CAR design to improve persistence and cytotoxicity is a focus of the current CAR-T study. Herein, we established a novel CAR structure by adding a full length 4-1BB co-stimulatory receptor to a 28Z-based second generation CAR that targets CD20. Our data indicated that this new 2028Z-4-1BB CAR-T cell showed improved proliferation and cytotoxic ability. To further understand the mechanism of action, we found that constitutive 4-1BB sensing significantly reduced the apoptosis of CAR-T cells, enhanced proliferation, and increased NF-κB pathway activation. Consistent with the enhanced proliferation and cytotoxicity in vitro , this new structure of CAR-T cells exhibited robust persistence and anti-tumor activity in a mouse xenograft lymphoma model. This work provides evidence for a new strategy to optimize the function of CAR-T against lymphoma., (Copyright © 2020 Dai, Han, Qi, Li, Li, Fan, Zhang, Zhang and Yang.)