SARS-CoV-2 spike-based virus-like particles incorporate influenza H1/N1 antigens and induce dual immunity in mice.

A vaccine effective against both SARS-CoV-2 and influenza A (IAV) viruses could represent a cost-effective strategy to reduce their combined public health burden as well as potential complications arising from co-infection. Based on previous findings that full-length SARS-CoV-2 spike (S) expression can induce high-level, enveloped VLP (eVLP) production in CHO cells, we tested whether IAV H1N1 hemagglutinin (H1) and neuraminidase (N1) could also be displayed on these particles. We found that co-incorporation of the IAV surface antigens in spike VLPs (S-VLPs) was highly efficient: upon transient co-expression of S + H1 or S + H1 + N1 in CHO cells, the resulting VLPs contained similar amounts of the SARS-CoV-2 S and IAV antigens.

Fabrication of thermo-responsive multicore microcapsules using a facile extrusion process.

A process employing extrusion was used to produce multicore microcapsules composed of multiple beads. The inner beads were made from κ-carrageenan (κ-c), a thermo-responsive linear sulphated polymer whose gelling temperature ranges at 40-60 °C, depending on the concentration of κ-c polymer and the amount of potassium chloride used for gelation. The resulting beads were then enveloped by chitosan through gelation with sodium triphosphate.

The Effect of Bismuth and Tin on Methane and Acetate Production in a Microbial Electrosynthesis Cell Fed with Carbon Dioxide.

This study investigates the impacts of bismuth and tin on the production of CH and volatile fatty acids in a microbial electrosynthesis cell with a continuous CO supply. First, the impact of several transition metal ions (Ni, Fe, Cu, Sn, Mn, MoO, and Bi) on hydrogenotrophic and acetoclastic methanogenic microbial activity was evaluated in a series of batch bottle tests incubated with anaerobic sludge and a pre-defined concentration of dissolved transition metals. While Cu is considered a promising catalyst for the electrocatalytic conversion of CO to short chain fatty acids such as acetate, its presence as a Cu ion was demonstrated to significantly inhibit the microbial production of CH and acetate.

Production, purification and immunogenicity of Gag virus-like particles carrying SARS-CoV-2 components.

The virus-like particle (VLP) platform is a robust inducer of humoral and cellular immune responses; hence, it has been used in vaccine development for several infectious diseases. In the current work, VLPs carrying SARS-CoV-2 Spike (S) protein (Wuhan strain) with an HIV-1 Gag core were produced using suspension HEK 293SF-3F6 cells by transient transfection. The Gag was fused with green fluorescent protein (GFP) for rapid quantification of the VLPs.

Preclinical evaluation of manufacturable SARS-CoV-2 spike virus-like particles produced in Chinese Hamster Ovary cells.

Background: As the COVID-19 pandemic continues to evolve, novel vaccines need to be developed that are readily manufacturable and provide clinical efficacy against emerging SARS-CoV-2 variants. Virus-like particles (VLPs) presenting the spike antigen at their surface offer remarkable benefits over other vaccine antigen formats; however, current SARS-CoV-2 VLP vaccines candidates in clinical development suffer from challenges including low volumetric productivity, poor spike antigen density, expression platform-driven divergent protein glycosylation and complex upstream/downstream processing requirements. Despite their extensive use for therapeutic protein manufacturing and proven ability to produce enveloped VLPs, Chinese Hamster Ovary (CHO) cells are rarely used for the commercial production of VLP-based vaccines.

Effect of Surface Functionality on the Rheological and Self-Assembly Properties of Chitin and Chitosan Nanocrystals and Use in Biopolymer Films.

Chitin nanocrystals (ChNCs) are unique to all other bio-derived nanomaterials in one aspect: the inherent presence of a nitrogen moiety. By tuning the chemical functionality of this nanomaterial, and thus its charge and hydrogen bonding capacity, one can heavily impact its macroscopic properties such as its rheological and self-assembly characteristics. In this study, two types of ChNCs are made using acid hydrolysis (AH-ChNCs) and oxidative (OX-ChNCs) pathways, unto which deacetylation using a solvent-free procedure is utilized to create chitosan nanocrystals (ChsNCs) of varying degree of deacetylation (DDA).

Inducible HEK293 AAV packaging cell lines expressing Rep proteins.

Packaging or producer cell lines for scalable recombinant adeno-associated virus (rAAV) production have been notoriously difficult to create due in part to the cytostatic nature of the Rep proteins required for AAV production. The most difficult challenge being creating AAV packaging cell lines using HEK293 parental cells, currently the best mammalian platform for rAAV production due to the constitutive expression of in HEK293 cells, a key transcription activator. Using suspension and serum-free media adapted HEK293SF carrying a gene expression regulation system induced by addition of cumate and coumermycin, we were able to create -expressing AAV packaging cells.

Carboxylated Cellulose Nanocrystals Decorated with Varying Molecular Weights of Poly(diallyldimethylammonium chloride) as Sustainable Antibacterial Agents.

Cationic nanomaterials are promising candidates for the development of effective antibacterial agents by taking advantage of the nanoscale effects as well as other exceptional physicochemical properties of nanomaterials. In this study, carboxylated cellulose nanocrystals (cCNCs) derived from softwood pulp were coated with cationic poly(diallyldimethylammonium chloride) of varying molecular weights. The resulting cationic carboxylated cellulose nanocrystals coated with poly(diallyldimethylammonium chloride) (cCNCs-PDDA) nanomaterials were characterized for their structural and morphological properties using Fourier transform infrared spectroscopy, dynamic light scattering, zeta potential, elemental analysis, transmission electron microscopy, and thermogravimetric analysis.

Exploring the functional attributes and in vitro starch and protein digestibility of pea flours having a wide range of amylose content.

In this study, ten pea flours covering a broad range of amylose content (37.2-77.6 %, dsb) were characterized for functional and nutritional properties.

Design of chitosan nanocrystals decorated with amino acids and peptides.

Antimicrobial peptides (AMPs) offer a great promise in designing new therapeutics due to their ability to interfere in bacterial growth by penetrating the cell wall. The overuse of antibiotics has resulted into antibiotic-resistant bacteria and AMPs could be an alternative to circumvent this resistance. Chitosan nanocrystals (ChsNCs) are rod-shaped polysaccharide-based nanomaterials, formed by deacetylation of seafood waste.

Evaluation of biocathode materials for microbial electrosynthesis of methane and acetate.

This study compares carbon felt (CF), granular activated carbon (GAC), and a conductive acrylonitrile butadiene styrene (cABS) polymer cathodes for CH and acetate production in a microbial electrosynthesis (MES) cell. At an applied voltage of 2.8 V and continuous CO flow, the CF biocathode MES cell showed the highest CH production rate of 1420 ± 225 mL V d (V = cathode volume), also producing acetate at a rate of 710 ± 110 mg V d.

High-Humidity Shaker Aging to Access Chitin and Cellulose Nanocrystals.

To unlock nature's potential for functional biomaterials, many efforts have been devoted to isolating the nanocrystalline domains within the supramolecular structure of polysaccharides. Yet, low reactivity and yield in aqueous systems along with excessive solvent usage hinders its development. In this report, the first solvent-free pathway to access carboxylated chitin and cellulose nanocrystals with excellent mass balance is described, relying on a new method coined high-humidity shaker aging (HHSA).

Selenite and selenate removal in a permeable flow-through bioelectrochemical barrier.

This study demonstrated the removal of selenite and selenate in flow-through permeable bioelectrochemical barriers (microbial electrolysis cells, MECs). The bioelectrochemical barriers consisted of cathode and anode electrode compartments filled with granular carbon or metallurgical coke. A voltage of 1.

Synthesis and Cytotoxicity Studies of Wood-Based Cationic Cellulose Nanocrystals as Potential Immunomodulators.

Polysaccharides have been shown to have immunomodulatory properties. Modulation of the immune system plays a crucial role in physiological processes as well as in the treatment and/or prevention of autoimmune and infectious diseases. Cellulose nanocrystals (CNCs) are derived from cellulose, the most abundant polysaccharide on the earth.

Carboxylated Chitosan Nanocrystals: A Synthetic Route and Application as Superior Support for Gold-Catalyzed Reactions.

In this study, we demonstrate for the first time the fabrication of carboxylated chitosan nanocrystals (ChsNC) with high degree of deacetylation (DDA) at >80% and narrow size distribution. We also studied its application as a sustainable support material for metal-based catalysts. Carboxylated chitin nanocrystals (ChNCs) were initially prepared through partial cleavage of glycosidic bonds in chitin by ammonium persulfate, with concurrent oxidation of chitin C6 primary alcohols to produce carboxylate groups on the surface of the ChNCs.

One-step antibody immobilization-based rapid and highly-sensitive sandwich ELISA procedure for potential in vitro diagnostics.

An improved enzyme-linked immunosorbent (ELISA) assay using one-step antibody immobilization has been developed for the detection of human fetuin A (HFA), a specific biomarker for atherosclerosis and hepatocellular carcinoma. The anti-HFA formed a stable complex with 3-aminopropyltriethoxysilane (APTES) by ionic and hydrophobic interactions. The complex adsorbed on microtiter plates exhibited a detection range of 4.

Preparation of well-dispersed gold/magnetite nanoparticles embedded on cellulose nanocrystals for efficient immobilization of papain enzyme.

A nanocomposite consisting of magnetite nanoparticles (Fe3O4NPs) and Au nanoparticles (AuNPs) embedded on cellulose nanocrystals (CNCs) was used as a magnetic support for the covalent conjugation of papain and facilitated recovery of this immobilized enzyme. Fe3O4NPs (10-20 nm in diameter) and AuNPs (3-7 nm in diameter) were stable and well-dispersed on the CNC surface. Energy-dispersive spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy were used to evaluate the surface composition and structure of CNC/Fe3O4NPs/AuNPs.

Catalysis using gold nanoparticles decorated on nanocrystalline cellulose.

A novel nanocomposite was prepared by deposition of carbonate-stabilized Au nanoparticles (AuNPs) onto the surface of poly(diallyldimethyl ammonium chloride) (PDDA)-coated carboxylated nanocrystalline cellulose (NCC). The hybrid material possessed AuNPs (1.45% by weight) with an average diameter of 2.

Effect of surface charge on the cellular uptake and cytotoxicity of fluorescent labeled cellulose nanocrystals.

Probing of cellular uptake and cytotoxicity was conducted for two fluorescent cellulose nanocrystals (CNCs): CNC-fluorescein isothiocyanate (FITC) and newly synthesized CNC-rhodamine B isothiocyanate (RBITC). The positively charged CNC-RBITC was uptaken by human embryonic kidney 293 (HEK 293) and Spodoptera frugiperda (Sf9) cells without affecting the cell membrane integrity. The cell viability assay and cell-based impedance spectroscopy revealed no noticeably cytotoxic effect of the CNC-RBITC conjugate.

Cellulose nanocrystal/gold nanoparticle composite as a matrix for enzyme immobilization.

A novel nanocomposite consisting of cellulose nanocrystals (CNCs) functionalized with gold nanoparticles (AuNPs) serving as an excellent support for enzyme immobilization with phenomenally high loading is presented in this work. As testing models, cyclodextrin glycosyl transferase (CGTase) and alcohol oxidase were conjugated on an activated CNC/AuNP matrix. This catalytic platform exhibits significant biocatalytic activity with excellent enzyme stability and without apparent loss of the original activity.

Selective nanomolar detection of dopamine using a boron-doped diamond electrode modified with an electropolymerized sulfobutylether-beta-cyclodextrin-doped poly(N-acetyltyramine) and polypyrrole composite film.

N-acetyltyramine was synthesized and electropolymerized together with a negatively charged sulfobutylether-beta-cyclodextrin on a boron-doped diamond (BDD) electrode followed by the electropolymerization of pyrrole to form a stable and permselective film for selective dopamine detection. The selectivity and sensitivity of the formed layer-by-layer film was governed by the sequence of deposition and the applied potential. Raman results showed a decrease in the peak intensity at 1329 cm(-1) (sp(3)), the main feature of BDD, upon each electrodeposition step.