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Anterior gradient 2 (AGR2) is often overexpressed in several types of cancer. AGR2 is cytoplasmic or secreted as an extracellular signal. Intracellular AGR2 properties and role in cancer have been well studied, but its extracellular function is largely unclear. It has been shown that extracellular AGR2 activates endothelial cells and fibroblasts in culture, but the mechanism of AGR2 signaling is not well elucidated. Here, we report that tumor secreted or externally added AGR2 translocates into cytoplasm by endocytosis, binds to β-catenin and further co-translocates to the nucleus in NIH3T3 fibroblasts. Externally added AGR2 also increased β-catenin expression, stability, and accumulation in the nucleus in both fibroblasts and cancer cells. External AGR2 rescued the expression of β-catenin, which was suppressed by EGFR inhibitor AG1478 indicating an alternative pathway to regulate β-catenin independent of EGFR signal. These effects were abolished when a monoclonal antibody against AGR2 was added to the experiments, confirming the effects are caused by AGR2 only. Putting together, our results show that extracellular AGR2 signaling pathway involves endocytosis mediated cellular translocation, direct binding and regulating β-catenin nuclear accumulation. It is also a target against tumor initiated AGR2 signaling to form and maintain tumor microenvironment.

Limited by harsh reaction conditions, the activation and utilization of methane were regarded as holy grail reaction. Co-reaction with methanol, successfully realizing mild conversion below 450 °C, provides practical strategies for methane conversion on metal-loaded ZSM-5 zeolites, especially for highly efficient Zn loaded ones. However, Zn species, regarded as active acid sites on the zeolite, have not been sufficiently studied. In this paper, Zn-loaded ZSM-5 zeolite was prepared, and Zn was modified by capacity, loading strategy, and treating atmosphere. Apparent methane conversion achieves 15.3% for 1.0Zn/Z-H2 (16.8% as calculated net conversion) with a significantly reduced loading of 1.0 wt.% against deactivation, which is among the best within related zeolite materials. Besides, compared to the MTA reaction, the addition of methane promotes the high-valued aromatic production from 49.4% to 54.8%, and inhibits the C10+ production from 7.8% to 3.6%. Notably, Zn2+ is found to be another active site different from the reported ZnOH+. Medium strong acid sites are proved to be beneficial for methane activation. This work provides suggestions for the modification of the Zn active site, in order to prepare highly efficient catalysts for methane activation and BTX production in co-reaction with methanol.

SARS-CoV-2 and its variants continue to threaten public health. The virus recognizes the host cell by attaching its Spike receptor-binding domain (RBD) to the host receptor ACE2. Therefore, RBD is a primary target for neutralizing antibodies and vaccines. Here we report the isolation, and biological and structural characterization of two single-chain antibodies (nanobodies, DL4 and DL28) from RBD-immunized alpaca. Both nanobodies bind Spike with affinities that exceeded the detection limit (picomolar) of the biolayer interferometry assay and neutralize the original SARS-CoV- 2 strain with IC50of 0.086 μg mL-1(DL4) and 0.385 μg mL-1(DL28). DL4 and a more potent, rationally designed mutant, neutralizes the Alpha variant as potently as the original strain but only displays marginal activity against the Beta variant. By contrast, the neutralizing activity of DL28, when in the Fc-fused divalent form, was less affected by the mutations in the Beta variant (IC50of 0.414 μg mL-1for Alpha, 1.060 μg mL-1for Beta). Crystal structure studies reveal that DL4 blocks ACE2-binding by direct competition, while DL28 neutralizes SARS-CoV-2 by an uncommon mechanism through which DL28 distorts the receptor-binding motif in RBD and hence prevents ACE2-binding. Our work provides two neutralizing nanobodies for potential therapeutic development and reveals an uncommon mechanism to design and screen novel neutralizing antibodies against SARS-CoV-2.

Currently, prostate cancer is the most frequently diagnosed cancer in males and chemotherapy is often essential for treating advanced prostate cancer. However, common chemotherapies for prostate cancer suffer from serious adverse effects due to poor drug targeting ability and tissue penetration, even with the help of conventional drug delivery systems. Here, encouraged by recent studies showing possible drug retention and tissue penetration advantages of unconventional non-spherical nanoparticles over conventional spherical nanoparticles, we design and construct a novel non-spherical nanodisk drug delivery system for treating prostate cancer. In order to enhance tumor-targeting capability, these nanodisks are further modified with targeting peptide CR(NMe)EKA, which recognizes extracellular matrix fibronectin and its complexes specifically expressed on the walls of tumor vessels and in tumor stroma. Compared with conventional nanospheres, the nanodisks achieve much higher drug accumulation at prostate tumor sites. When loaded with paclitaxel, the CR(NMe)EKA-modified nanodisks display superior antitumor efficacy to free paclitaxel, unmodified nanodisks and nanospheres. In summary, our study provides an attractive therapeutic strategy for targeted therapy against prostate cancer with simple preparation, high efficiency and low toxicity, and supplements a theoretical support for treatments realized by different shaped nanoplatforms. Our study also offers valuable data for understanding biological effects of non-spherical nanodisks and highlights the great potential of unconventional nanoparticles in biomedical applications.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a β-coronavirus, is the causative agent of the COVID-19 pandemic. Like for other coronaviruses, its particles are composed of four structural proteins, namely Spike S, Envelope E, Membrane M and Nucleoprotein N proteins. The involvement of each of these proteins and their interplays during the assembly process of this new virus are poorly-defined and are likely β-coronavirus-type different. Therefore, we sought to investigate how SARS-CoV-2 behaves for its assembly by expression assays of S, in combination with E, M and/or N. By combining biochemical and imaging assays, we showed that E and M regulate intracellular trafficking of S and hence its furin-mediated processing. Indeed, our imaging data revealed that S remains at ERGIC or Golgi compartments upon expression of E or M, like for SARS-CoV-2 infected cells. By studying a mutant of S, we showed that its cytoplasmic tail, and more specifically, its C-terminal retrieval motif, is required for the M-mediated retention in the ERGIC, whereas E induces S retention by modulating the cell secretory pathway. We also highlighted that E and M induce a specific maturation of S N-glycosylation, which is observed on particles and lysates from infected cells independently of its mechanisms of intracellular retention. Finally, we showed that both M, E and N are required for optimal production of virus-like-proteins. Altogether, our results indicated that E and M proteins influence the properties of S proteins to promote assembly of viral particles. Our results therefore highlight both similarities and dissimilarities in these events, as compared to other β-coronaviruses.Author SummaryThe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the COVID-19 pandemic. Its viral particles are composed of four structural proteins, namely Spike S, Envelope E, Membrane M and Nucleoprotein N proteins, though their involvement in the virion assembly remain unknown for this particular coronavirus. Here we showed that presence of E and M influence the localization and maturation of S protein, in term of cleavage and N-glycosylation maturation. Indeed, E protein is able to slow down the cell secretory pathway whereas M-induced retention of S requires the retrieval motif in S C-terminus. We also highlighted that E and M might regulate the N glycosylation maturation of S independently of its intracellular retention mechanism. Finally, we showed that the four structural proteins are required for optimal formation of virus-like particles, highlighting the involvement of N, E and M in assembly of infectious particles. Altogether, our results highlight both similarities and dissimilarities in these events, as compared to other β-coronaviruses.

SARS-CoV-2, the causative agent of COVID-191, recognizes host cells by attaching its receptor-binding domain (RBD) to the host receptor ACE22-7. Neutralizing antibodies that block RBD-ACE2 interaction have been a major focus for therapeutic development8-18. Llama-derived single-domain antibodies (nanobodies, ~15 kDa) offer advantages including ease of production and possibility for direct delivery to the lungs by nebulization19, which are attractive features for bio-drugs against the global respiratory disease. Here, we generated 99 synthetic nanobodies (sybodies) by in vitro selection using three libraries. The best sybody, MR3 bound to RBD with high affinity (KD = 1.0 nM) and showed high neutralization activity against SARS-CoV-2 pseudoviruses (IC50 = 0.40 μg mL-1). Structural, biochemical, and biological characterization of sybodies suggest a common neutralizing mechanism, in which the RBD-ACE2 interaction is competitively inhibited by sybodies. Various forms of sybodies with improved potency were generated by structure-based design, biparatopic construction, and divalent engineering. Among these, a divalent MR3 conjugated with the albumin-binding domain for prolonged half-life displayed highest potency (IC50 = 12 ng mL-1) and protected mice from live SARS-CoV-2 challenge. Our results pave the way to the development of therapeutic nanobodies against COVID-19 and present a strategy for rapid responses for future outbreaks.

IL13Rα2 shows high expression in different types of tumors and can be a target for cancer therapy in humans due to its poor prognosis. The aim of our study is to characterize and investigate the effect of interleukin-13 receptor subunit alpha-2monoclonal antibody mAb15D8 on lung cancer cells in vitro and in vivo by blocking its specific epitope in IL13Rα2 antigen. The mAb15D8 blocking epitope was analyzed through the mutagenesis of IL13Rα2 and confirmed with western blot. We found that the IL13Rα2 epitope recognized by mAb15D8 antibody is a new binding site localized in the fibronectin-III domain-1 of IL13Rα2 antigen. Moreover, the mAb15D8 obviously reduced cell proliferation, migration of H460, A549, SKOV3, and B16F10 cells. Treatment with mAb15D8 significantly reduced the H460 xenograft tumor formation and growth in nude mice and inhibited B16F10 tumor metastasis and increased survival in C57BL/6 mice. Pharmacokinetic and toxicological analysis demonstrated the safety of mAb15D8 as a potential therapeutic agent. We developed a novel mouse monoclonal antibody against IL13Rα2 which binds to specific epitope on IL13Rα2 antigen. In vivo treatment with the antibody significantly reduced tumor growth and lung metastasis and prolonged survival. These results suggest mAb15D8 antibody as a potential therapeutic agent for cancer therapy.

Optical parametric chirped-pulse amplification (OPCPA) provides an efficient route to push ultrafast pulses toward ultrahigh peak powers. However, in high average power regime, the unavoidable thermal effects in nonlinear crystals will intrinsically destroy the phase-matching (PM) condition, which fundamentally limit average power scaling. Here, we present a theoretical design of high average power OPCPA based on simultaneous temperature and wavelength insensitive PM. By regulating the temperature set for PM as well as the wavelength of interacting waves in lithium triborate crystal, the noncollinear angles for temperature insensitive PM and wavelength insensitive PM will coincide and thus ensures simultaneous temperature and wavelength insensitive PM condition. We investigate the performances of the proposed PM scheme in comparison with traditional wavelength insensitive noncollinear PM. Because of the larger temperature bandwidth, higher average power can be anticipated in OPCPA with the proposed PM scheme. Besides, the large spectral bandwidth also allows the amplification of sub-10 fs pulses in the visible spectral range. The proposed PM scheme will provide a promising approach in generating ultrashort pulses with high peak and average powers.

Lignin-based supercapacitors have received more attention for developing renewable biomass energy storage devices due to multiple pseudocapacitive functional groups in the natural lignin biomolecules and their derivatives. Herein, we confirmed the electrochemical activities of lignin-based composite were greatly boosted by coupling of oxidized kraft lignin (OKL) with hierarchical porous nitrogen-dopped carbon (NC). The synergetic effect between pseudocapacitive groups (mainly hydroquinone group) in OKL and macroporous-mesoporous carbon with interpenetration structure and nitrogen doping was verified by FT-IR, XPS and electrochemical characterizations. The capacitance of OKL/NC composite was achieved 412 F g−1 at 1 A g−1 in an acidic system, which is a twice increase compared to the capacitance (154 F g−1) of NC.

Lignin-derived aromatic oligomers (LDAOs) are the primary components of lignin depolymerization products. They are typically utilized as renewable crosslinking agents or resin materials with a considerably lower application value than aromatic monomers. Notably, LDAOs are rich in quinone groups, which enable storage and release of charges. In this work, the feasibility of LDAOs as renewable charge storage materials was investigated. LDAOs were first reacted with formaldehyde to generate a synthetic polymer (SP-AOF) via a phenol-formaldehyde condensation reaction. SP-AOF was subsequently incorporated with reduced graphene oxide (rGO), namely rGO/SP-AOF. As expected, the hybrid electrode exhibited high specific capacitance (250 F/g), which was approximately three times higher than that of rGO (87 F/g). This was due to the presence of quinone groups in SP-AOF, which could contribute to the overall capacitance with pseudocapacitance. Moreover, the hybrid electrode was able to deliver a high specific capacitance of 210 F/g even at a high specific current of 10 A/g. 1H−13C heteronuclear single quantum coherence nuclear magnetic resonance (2D HSQC NMR) and phosphorus nuclear magnetic resonance spectroscopy (31P NMR) analyses revealed that SP-AOF displayed higher quinone content (3.76 mmol/g) than commercially available lignin (organosolv and alkali lignin), which resulted in higher energy storage performance. This study provides a promising strategy for the utilization of aromatic oligomers as raw materials to manufacture high-performance lignin-derived energy storage materials.

Dual-porosity materials containing both macropores and mesopores are highly desired in many fields. In this work, we prepared dual-porosity Mn2O3 cube materials with large-pore mesopores, in which, macropores are made by using carbon spheres as the hard templates, while the mesopores are produced via a template-free route. The attained dual-porosity Mn2O3 materials have 24 nm of large-pore mesopores and 700 nm of macropores. Besides, the achieved materials own cubic morphologies with particle sizes as large as 6.0 μm, making them separable in the solution by a facile natural sedimentation. Dye adsorption measurements reveal that the dual-porosity materials possess a very high maximum adsorption capacity of 125.6 mg/g, much larger than many reported materials. Particularly, the adsorbents can be recycled and the dye removal efficiency can be well maintained at 98% after four cycles. Adsorption isotherm and kinetics show that the Langmuir model and the pseudo-second-order kinetics model can well describe the adsorption process of Congo Red on the dual-porosity Mn2O3 cube materials. In brief, the reported dual-porosity Mn2O3 demonstrates a good example for controlled preparation of dual-porosity materials with large-pore mesopores, and the macropore-mesopore dual-porosity distribution is good for mass transfer in dye adsorption application.

Recent efforts to improve the capacitances of Kraft lignin (KL) in supercapacitors have mainly focused on screening KL substrates, which could either compensate the poor conductivity of KL or directly contribute to the capacitance. However, increasing the pseudocapacitance contributed by KL itself, through hydroquinone/quinone redox cycles, remains a challenge, owing to the roughly fixed content of hydroquinone species in natural KL. In this study, the capacitance of KL is greatly improved by using a functional-group modification strategy in which methoxy groups in KL are selectively converted into phenolic hydroxy groups, which facilitate the formation of additional hydroquinone moieties and thus lead to higher pseudocapacitances. The oxidized KL materials show up to 25.6 % enhancement of the phenolic hydroxy content in comparison to raw KL, which results in 21.9 % capacitance improvement from 322 to 390 F g-1 at 0.5 A g-1 in an acidic system.

A key step to the SARS-CoV-2 infection is the attachment of its Spike receptor-binding domain (S RBD) to the host receptor ACE2. Considerable research has been devoted to the development of neutralizing antibodies, including llama-derived single-chain nanobodies, to target the receptor-binding motif (RBM) and to block ACE2-RBD binding. Simple and effective strategies to increase potency are desirable for such studies when antibodies are only modestly effective. Here, we identify and characterize a high-affinity synthetic nanobody (sybody, SR31) as a fusion partner to improve the potency of RBM-antibodies. Crystallographic studies reveal that SR31 binds to RBD at a conserved and ‘greasy’ site distal to RBM. Although SR31 distorts RBD at the interface, it does not perturb the RBM conformation, hence displaying no neutralizing activities itself. However, fusing SR31 to two modestly neutralizing sybodies dramatically increases their affinity for RBD and neutralization activity against SARS-CoV-2 pseudovirus. Our work presents a tool protein and an efficient strategy to improve nanobody potency., Author summary SARS-CoV-2 relies on the receptor-binding domain (RBD) of its envelope Spike protein to recognize and infect host cells. RBD is therefore an immunological hotspot to generate antibodies for therapeutic and detection purposes. Binding affinity is one of the key characteristics of such antibodies. Here, we report a single-chain antibody (nanobody, ~14 kDa) that binds RBD with nanomolar affinity. The nanobody, dubbed SR31, binds RBD at an epitope distal to the receptor-binding motif (RBM) which is the target of most neutralizing antibodies. SR31 can therefore bind RBD in addition to RBM-binders, and increase their affinity and potency by avidity effects when used as a fusion partner. Compared to other in vitro affinity maturation techniques such as library screening and structure-based design, the fusion strategy offers advantages in speed and simplicity. In addition, SR31, together with RBD-targeting nanobodies recognizing a wide spectrum of epitopes, provides a useful toolkit to probe epitopes of uncharacterized antibodies by competitive binding.

This paper presented a novel microemulsion-based method for the preparation of MgO nanomaterials. Briefly, in a paraffin-in-water microemulsion system, we firstly synthesized Mg5(CO3)4(OH)2·4H2O/paraffin composites, the precursor of MgO, via an interface-controlled homogenous precipitation. By calcinating the composite precursor at different temperatures, MgO nanomaterials with varied morphologies could be obtained. A flower-like 3D hierarchical structure was achieved when applying lower calcination temperatures, which indeed preserves the morphology of the composite precursor. While at higher calcination temperatures, one can get the well-defined MgO nanoparticles. The prepared materials were thoroughly characterized by XRD, SEM and BET methods, and their application as adsorbents to remove Congo red from wastewater was demonstrated.

The flexibility and hydrophilicity of nanogels suggest their potential for the creation of nanocarriers with good colloidal stability and stimulative ability. In the present study, biocompatible AGP and AGPA nanogels with triple-stimulative properties (thermosensitivity, pH sensitivity, and redox sensitivity) were prepared by incorporating poly(N-isopropylacrylamide) (PNIPAM) or poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAM-AA)) into alginate (AG) emulsion nanodrops, followed by fixation with a disulfide-containing molecule (cystamine dihydrochloride (Cys)). Compared to AG/PNIPAM(AGP) nanogels, AG/P(NIPAM-AA) (AGPA) nanogels exhibited more sensitive volumetric expansion by switching the temperature from 40 to 25 °C under physiological medium. This expansion occurs because P(NIPAM-AA) with -COOH groups can be fixed inside the nanogels via chemical bonding with Cys, whereas PNIPAM was encapsulated in the nanogels through simple physical interactions with the AG matrix. AGPA nanogels carrying an anticancer drug tend to easily enter cells upon heating, thereby exerting toxicity through a cold shock and reverse thermally induced release of an anticancer drug. Upon internalization inside cells, the nanogels use the reducible and acidic intracellular environments to effectively release the drug to the nucleus to impart anticancer activity. These results demonstrate that multifunctional nanogels may be used as a general platform for therapeutic delivery.

In order to overcome the multidrug resistance (MDR) of tumor cells, it is very important to develop nanocarriers which can effectively load drugs while releasing them in a sequential way. Herein, nanohybrids with such properties have been fabricated by a first loading of one anticancer drug onto a silicate nanodisk (Laponite (LP), 25 nm in diameter and 0.92 nm in thickness) and a subsequent assembly with a pH sensitive poly(N-vinylpyrrolidone) (PVP) as a protective layer, followed by a loading of with another anticancer drug. The resulting nanohybrids (LDPM) present a high drug encapsulation efficiency and long-term colloidal stability. However, if the two drugs are loaded onto LP before PVP decoration, the formed particles tend to form microsized aggregates with poor colloidal stability. In vitro release study indicates that LDPM can deliver the anticancer drugs in a sequential way, which can be further accelerated under acidic microenvironments mimicking both solid tumor and endo-lysosomal compartments, exerting synergistic anticancer cytotoxicity. The drug-mediated formation of nanocarriers may enlighten a design of novel nanoplatform for co-delivery of therapeutic agents, beyond anticancer drugs, in a combinative way for drug delivery applications.

Targeting cellular metabolism is becoming a hallmark to overcome drug resistance in breast cancer treatment. Activation of fatty acid synthase (FASN) has been shown to promote breast cancer cell growth. However, there is no concrete report underlying the mechanism associated with mitochondrial dysfunction in relation to fatty acid synthase inhibition-induced apoptosis in breast cancer cells. The current study is aimed at exploring the effect of the novel manganese (Mn) complex, labeled as PdpaMn, on lipid metabolism and mitochondrial function in breast cancer cells. Herein, we observed that PdpaMn displayed strong cytotoxicity on breast cancer cell lines and selectively targeted the tumor without affecting the normal organs or cells in vivo. We also observed that PdpaMn could bind to TE domain of FASN and decrease the activity and the level of expression of FASN, which is an indication that FASN could serve as a target of PdpaMn. In addition, we demonstrated that PdpaMn increased intrinsic apoptosis in breast cancer cells relayed by a suppressed the level of expression of FASN, followed by the release of mitochondrial cytochrome c and the activation of caspases-9. Instigated by the above observations, we hypothesized that PdpaMn-induced apoptosis events are dependent on mitochondrial dysfunction. Indeed, we found that mitochondrial membrane potential (MMP) collapse, mitochondrial oxygen consumption reduction and adenosine triphosphate (ATP) release were deeply repressed. Furthermore, our results showed that PdpaMn significantly increased the reactive oxygen species (ROS) production, and the protection conferred by the free radical scavenger N-acetyl-cysteine (NAC) indicates that PdpaMn-induced apoptosis through an oxidative stress-associated mechanism. More so, the above results have demonstrated that mitochondrial dysfunction participated in FASN inhibition-induce apoptosis in breast cancer cells by PdpaMn. Therefore, PdpaMn may be considered as a good candidate for anti-breast cancer therapeutic option.

Optical parametric chirped-pulse amplification (OPCPA) has been demonstrated to be a promising approach for pushing femtosecond pulses towards ultra-high peak powers. However, the future success of OPCPA strongly relies on the ability to manipulate its phase-matching (PM) configuration. When a high average power pump laser is involved, the thermal effects in nonlinear crystals induce phase-mismatch distortions that pose an inherent limitation on the conversion efficiency. Here, we demonstrate that the noncollinear configuration previously adopted for wavelength-insensitive PM can be employed for temperature-insensitive PM when the noncollinear angle is properly reset. Simultaneous temperature- and wavelength-insensitive PM is realized for the first time by imposing such a temperature-insensitive noncollinear configuration with an angularly dispersed seed signal. Based on the lithium triborate crystal, the proposed noncollinear achromatic PM has a thermal acceptance 6 times larger than that of the conventional wavelength-insensitive noncollinear PM and has a sufficient spectral acceptance to support pulse durations of ~20 fs at 800 nm. These achievements open new possibilities for generating ultra-high peak power lasers with high average power.

Slow and fast light are ubiquitous in optical amplifiers. In this Letter, we show for the first time, to the best of our knowledge, that optical parametric amplification (OPA) in chirped quasi-phase-matching structures can act as a platform for group-velocity control in the femtosecond regime. The resonant cascaded nonlinear phase underlies the group-velocity control, which manifests an unusual effect that both slow and fast light can be achieved under the normal condition of signal amplification. As numerically demonstrated in the OPA based on the lithium niobate crystal, the signal and idler pulse can be significantly delayed in time comparable to the signal duration and can also keep high fidelity for durations down to 100 fs until the crystal dispersion becomes effective. The broad bandwidth, large group delay, and direct compatibility with integrated optics will make the proposed platform attractive to both fundamental research and applied science.

In high-average-power second-harmonic generation (SHG) devices, the unavoidable thermal distortion induces a nonuniform phase mismatch that poses an inherent limitation on the conversion efficiency. Here we introduce a temperature-insensitive noncollinear (TIN) phase-matching scheme, which can significantly improve the performance of high-power SHG devices and is versatile to a broad range of laser wavelengths. In the proof-of-principle experiment with a lithium triborate crystal and a 1053 nm nanosecond laser, we demonstrate a large temperature bandwidth of ∼50 K×cm1/2 and a high SHG efficiency of ∼56%. This temperature bandwidth is 13 times that of the conventional collinear phase matching. We also numerically investigate the performance of the proposed TIN phase-matching scheme in high-power lasers. The demonstrated large temperature bandwidth allows efficient SHG in the high-power regime of 5–10 kW. The simplicity, high efficiency, and wavelength versatility will make the TIN phase matching attractive for wide applications in high-power lasers.