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Human platelets (PLTs) are vulnerable to unfavorable conditions, and their adequate supply is limited by strict transportation conditions. We report here that PLTs preserved under three-dimensional (3D) conditions using novel biomimetic nanofiber peptides showed reduced apoptosis compared with classical PLTs stored at 22 °C and facilitated the storage and transportation of PLTs. The mechanism of PLT 3D preservation involves the formation of cross-links and a 3D nanofibrous network by a self-assembled peptide scaffold material at physiological conditions after initiation by triggers in plasma. PLTs adhere to the surface of the nanofibrous network to facilitate the 3D distribution of PLTs. The 3D microstructure, rheological properties, and effect on the inflammatory response and hemolysis were evaluated. Compared to traditional PLTs stored at 22 °C, PLTs subjected to 3D preservation showed similar morphology, number, aggregation activity, and reduced apoptosis. The detection of the reactive oxygen species (ROS) levels demonstrated that both reduced intracellular and mitochondrial ROS levels were correlated with reduced apoptosis. This study reveals a new 3D preservation method for PLTs based on the use of novel biomimetic nanofiber peptides that presents an attractive opportunity for various biomedical applications.

The sulfur-coordinated organoiridium(III) complexes pbtIrSS and ppyIrSS, which contain C,N and S,S (dithione) chelating ligands, were found to inhibit breast cancer tumorigenesis and metastasis by targeting Wnt/β-catenin signaling for the first time. Treatment with pbtIrSS and ppyIrSS induces the degradation of LRP6, thereby decreasing the protein levels of DVL2, β-catenin and activated β-catenin, resulting in downregulation of Wnt target genes CD44 and survivin. Additionally, pbtIrSS and ppyIrSS can suppress cell migration and invasion of breast cancer cells. Furthermore, both complexes show the ability to inhibit sphere formation and mediate the stemness properties of breast cancer cells. Importantly, pbtIrSS exerts potent anti-tumor and anti-metastasis effects in mouse xenograft models through the blockage of Wnt/β-catenin signaling. Taken together, our results indicate that pbtIrSS has great potential to be developed as a breast cancer therapeutic agent with a novel mechanism.

Hydrophobic interaction chromatography (HIC) as an indispensable method for protein purification has attracted considerable attentions of researchers as well as biopharmaceutical industries. However, the operation pressure-drop and flow rate of the typical HIC porous resin beads are less than satisfactory. To address these issues, composite nanofibrous membranes (CNFMs) with controllable wettability have been developed by multi-component electrospinning of polystyrene/polyacrylonitrile (PS/PAN), and further by regulating the solution properties and introducing SiO 2 nanoparticles in, CNFMs with proper wettability and large surface area of 23.6 m−2 g−1 were fabricated. The obtained CNFMs showed a high static adsorption capacity of 78 mg g−1 and fast adsorption process within 30 min. Additionally, a high saturation dynamic binding capacity of 39.6 mg ml−1 was obtained under a low pressure-drop of 200 Pa, which surpassed the commercial HIC membrane media. Moreover, these membranes have a selectivity toward the protein with higher hydrophobicity , and proteins adsorbed on the membranes can be eluted with 10 wt% ethanol aqueous solution. Therefore, such a successful fabrication of nanofibrous membranes with outstanding hydrophobic protein adsorption performance could provide a promising platform to prepare economical and inspiring HIC media in the future.

Background The pathogenesis of transfusion-related acute lung injury (TRALI) progress is incompletely understood, and specific therapies for TRALI are lacking. Alveolar macrophages (AMs) are critical for initiation and resolution of lung inflammation. However, the role of AMs in the pathogenesis of TRALI-associated lung failure is poorly understood. Study design and methods Mouse model for in vivo imaging of interleukin (IL)-6 activation in AMs was established by intratracheal instillation of a lentiviral vector carrying the luciferase reporter gene. The TRALI mouse model was produced by intraperitoneal lipopolysaccharide plus intravenous major histocompatibility complex Class I monoclonal antibody treatment. We focused on the changes in AMs in the lung during TRALI and examined whether targeting AMs is an effective strategy to alleviate this condition. Measurements and main results We confirmed that TRALI progress is accompanied by IL-6 activation in AMs. Further study showed that AMs undergo M1 activation during TRALI progress. AM depletion protected mice from TRALI, and transfusion of M1-polarized AMs into 34-1-2 s-treated mice elevated acute lung injury, indicating that the severity of TRALI was able to be ameliorated by targeting AM polarization. Next, we showed that α1 -antitrypsin (AAT) expression improved lung injury by modulating the production of IL-6 in AMs and decreased polarization of AMs toward the M1 phenotype. Conclusions M1-polarized AMs are crucial in a mouse model of TRALI, and AAT may serve as a future treatment for TRALI by regulating the polarization of AMs.

The development of chromatographic media with superb adsorption capacity and large processing throughput is of great importance for highly efficient protein adsorption and separation, yet still faces a huge challenge. Herein, a new kind of butane tetracarboxylic acid (BTCA) functionalized ethylene vinyl alcohol (EVAL) nanofibrous membranes (BTCA@EVAL NFM)-based chromatographic media is fabricated, for the first time, by combining blend electrospinning technique with in-situ modification technology. The resulting BTCA@EVAL NFM possesses an enhanced equilibrium protein adsorption capability (716 mg g−1), a high saturated dynamic protein binding capacity (490 mg g−1), and a distinctive selectivity towards positively charged proteins, which are attributed to the synergistic effects of the hydrophilic EVAL nanofibrous matrix and the plentiful carboxyl groups introduced by BTCA. Besides, benefiting from its stable physical and chemical structures, the membrane also presents excellent acid and alkaline resistance as well as good reusability. Significantly, the BTCA@EVAL NFM can directly extract lysozyme from egg white with a relatively large capture capability of 353 mg g−1, highlighting its superb potential practicability. We sincerely hope that this new design concept and the highly effective nanofiber-based chromatographic media can provide some guidance for the further development of bio-separation and purification.

Hydrophobic interaction chromatography (HIC) as an indispensable method for protein purification has attracted considerable attentions of researchers as well as biopharmaceutical industries. However, the low binding capacity and slow adsorption rate of the currently available HIC media lead to a little supply and high price of the highly purified proteins. Herein, nanofibrous membranes with hydrophobic binding sites were developed for HIC by directly coupling phenyl glycidyl ether on the hydrolyzed cellulose acetate nanofiber membrane (cellulose-phenyl NFM). Scanning electron microscope (SEM), water contact angle (WCA), Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET) surface area analysis and capillary flow porometer (CFP) were applied to evaluate the physically and chemically structural transformation. The obtained cellulose-phenyl NFMs showed a proper hydrophilcity (WCA = 37°), a relatively high BET surface area (3.6 times the surface area of commercial fibrous membranes), and tortuous-channel structure with through-hole size in the range of 0.25–1.2 μm, which led to a little non-specificity adsorption, high bovine serum albumin adsorption capacity of 118 mg g−1, fast adsorption process within 12 h, good long-term stability and reusability. Moreover, compared with traditional modification methods which always include activation and graft two steps, direct coupling method is more efficient for HIC media fabrication. Therefore, cellulose-phenyl NFMs with outstanding protein adsorption performance could be a kind of promising candidate for HIC.

The sulfur-coordinated organoiridium(III) complexes pbtIrSS and ppyIrSS, which contain C,N and S,S (dithione) chelating ligands, were found to inhibit breast cancer tumorigenesis and metastasis by targeting Wnt/β-catenin signaling for the first time. Treatment with pbtIrSS and ppyIrSS induces the degradation of LRP6, thereby decreasing the protein levels of DVL2, β-catenin and activated β-catenin, resulting in downregulation of Wnt target genes CD44 and survivin. Additionally, pbtIrSS and ppyIrSS can suppress cell migration and invasion of breast cancer cells. Furthermore, both complexes show the ability to inhibit sphere formation and mediate the stemness properties of breast cancer cells. Importantly, pbtIrSS exerts potent anti-tumor and anti-metastasis effects in mouse xenograft models through the blockage of Wnt/β-catenin signaling. Taken together, our results indicate that pbtIrSS has great potential to be developed as a breast cancer therapeutic agent with a novel mechanism.

Creating adsorptive materials for the fast, efficient, and high-throughput adsorption and purification of proteins is critical to meet the great demands for highly purified proteins, yet it has proven to be a highly challenging task. Here, we report that cross-linked and highly carboxylated poly(vinyl alcohol) (PVA) nanofibrous membranes were fabricated by a combination of electrospinning and the in situ graft polymerization of PVA and maleic anhydride (MAH) under mild conditions. Taking advantage of the large surface area available for protein binding, the highly tortuous porous structure, and the robust mechanical properties, the resultant PVA/MAH nanofibrous membranes exhibited a good integrated adsorption performance towards lysozyme, including a superior adsorption capacity of 177 mg g-1, fast adsorption equilibrium within 4 h, good selectivity, and good reversibility. Moreover, the saturation dynamic adsorption amount towards lysozyme reached 159 mg g-1 under 750 Pa driven solely by gravity, which conformed to the specified requirements for high adsorption capacity under relatively low pressure drops. Furthermore, the adsorption performance towards a protein mixture was analyzed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and the resultant PVA/MAH nanofibrous membranes retained excellent stability under depyrogenation conditions. The successful fabrication of such fascinating nanofibrous materials by using this simple and intriguing approach may provide new insights into the design and development of adsorptive materials for the purification of proteins with superior adsorption performance.

Fabricating metal-chelating affinity materials with excellent protein adsorption and isolation properties is of great significance in numerous biotechnological fields, yet still face huge challenges. Herein, we successfully developed a new kind of nanofiber based metal-chelating affinity membranes by orderly modifying the electrospun regenerated cellulose nanofibrous membranes (RC NFMs) with intermediate bridging agent of cyanuric chloride (CC), chelating agent of iminodiacetic acid (IDA) and affinity ligand of Fe3+ ions. The resultant Fe3+ ions immobilized RC NFMs (RC-CC-IDA-Fe3+ NFMs) exhibited a high lysozyme adsorption amount of 365 mg g-1 within the fast equilibrium adsorption time of 4 hours. Meanwhile, the performance of RC-CC-IDA-Fe3+ NFMs could be facilely regulated by controlling the properties and concentration of protein solutions. Moreover, the obtained nanofibrous affinity materials also possessed superior cycle performance and excellent regeneration ability. Undoubtedly, the successful fabrication of efficient RC-CC-IDA-Fe3+ NFMs might provide a new kind of affinity adsorbent for protein purification and other potential biotechnological fields.

Construction ion-exchange membranes with superb biomolecules adsorption and purification performance plays a greatly important role in the fields of biotechnological and biopharmaceutical industry, yet still remains an extremely challenging. Herein, we in situ synthesized the cis-butenedioic anhydride grafted poly(vinyl alcohol) hydrogel nanofibrous membranes (CBA-g-PVA HNFM) by combining electrospinning technique with the grafting-copolymerization crosslinking. Taking advantages of the large specific surface area which could provide numerous sites available for functional groups and biomolecules binding, highly tortuous and interconnected porous channel for biomolecules transfer, and enhanced mechanical strength, the resultant CBA-g-PVA HNFM exhibited relatively high binding amount of 170 mg g−1, rapid equilibrium time of 8 h towards the biomolecule template of lysozyme, and the performance could be tailored by regulating the buffer properties and protein concentrations. Additionally, the resultant functional HNFM also possessed superior acid resistance property, excellent reversibility and regeneration performance. More importantly, the obtained CBA-g-PVA HNFM could directly extract lysozyme from fresh chicken eggs with capacity of 125 mg g−1, exhibiting excellent practical application properties. The fabrication of proposed CBA-g-PVA HNFM offers a feasible alternative for construction of ion-exchange chromatograph column for bio-separation and purification engineering.

With the objective of investigating the acute activation of inflammatory cascades upon exposure to gold nanoparticles (GNPs) as well as detailing the mechanisms, a reporter mouse model that allows for non-invasive and longitudinal imaging of hepatic acute-phase serum amyloid A (SAA) activation is constructed. The model is able to visualize SAA activation at the transcriptional stage, with higher sensitivity than serum protein detection by ELISA. GNPs of various sizes (10-80 nm) and geometries are assessed using the reporter mice with results demonstrating that 50 nm nanospheres (GNS50) possess the highest capacity to induce hepatic SAA activation. Detailed analysis uncovers that resident macrophages in the liver are the main origins of these cytokines and that the exposure to GNS50 significantly induces the M1 macrophage phenotype. Moreover, those M1-polarized macrophages, together with the subsequently secreted pro-inflammatory cytokines, exert effects on hepatocytes and then initiate SAA transcription through the NF-κB signal pathway. The results detail the sequential reactions to GNPs among macrophages, inflammatory mediators, and SAA-synthesizing hepatocytes, which shed light on the acute effects of GNPs on the body. In addition, the established in situ and highly sensitive SAA detection system is expected to have vast applications in evaluating NP-induced acute inflammatory reactions.

Daylight-driven antimicrobial nanomaterials serve as a novel barrier for transmission of emerging infectious diseases., Emerging infectious diseases (EIDs) are a significant burden on global economies and public health. Most present personal protective equipment used to prevent EID transmission and infections is typically devoid of antimicrobial activity. We report on green bioprotective nanofibrous membranes (RNMs) with rechargeable antibacterial and antiviral activities that can effectively produce biocidal reactive oxygen species (ROS) solely driven by the daylight. The premise of the design is that the photoactive RNMs can store the biocidal activity under light irradiation and readily release ROS under dim light or dark conditions, making the biocidal function “always online.” The resulting RNMs exhibit integrated properties of fast ROS production, ease of activity storing, long-term durability, robust breathability, interception of fine particles (>99%), and high bactericidal (>99.9999%) and virucidal (>99.999%) efficacy, which enabled to serve as a scalable biocidal layer for protective equipment by providing contact killing against pathogens either in aerosol or in liquid forms. The successful synthesis of these fascinating materials may provide new insights into the development of protection materials in a sustainable, self-recharging, and structurally adaptive form.

Construction of adsorptive materials for simple, efficient, and high-throughput adsorption of proteins is critical to meet the great demands of highly purified proteins in biotechnological and biopharmaceutical industry; however, it has proven extremely challenging. Here, we report a cost-effective strategy to create carbonyl groups surface-functionalized nanofibrous membranes under mild conditions for positively charged protein adsorption. Our approach allows maleic anhydride to in situ graft on cellulose nanofibrous membranes (CMA) to construct adsorptive membranes with large surface area and tortuous porous structure. Thereby, the resultant CMA membranes exhibited high adsorption capacity of 160 mg g(-1), fast equilibrium within 12 h, and good reversibility to lysozyme. Moreover, the dynamic adsorption was performed under low pressure-drops (750 Pa), with a relatively high saturation adsorption amount of 118 mg g(-1), which matched well with the requirements for proteins purification. Considering the excellent adsorption performance of the as-prepared adsorptive membranes, this simple and intriguing approach may pave a way for the design and development of robust and cost-effective adsorption membranes to meet the great demands for fast and efficient adsorption of positively charged proteins.

In the current work, a one-step, washing-free, homogeneous nanosensor assay has been constructed to sensitively detect hepatitis B surface antigen (HBsAg) based on the light scattering property of gold nanoparticles (GNPs) through a sandwich model. The two nanoprobes in this study were designed by conjugating monoclonal and polyclonal hepatitis B surface antibody (HBsAb) onto the GNPs of different diameters. First, the detection behavior of the combinations of different sizes of GNPs was evaluated and the optimized combination was determined. In analyzing HBsAg in Tris-HCl buffer, such bioassay composed of GNPs of approximately 50 and 100 nm has a limit of detection (LOD) as high as 0.005 IU/ml and a dose-dependent response ranging from 0.005 to 1 IU/ml, which indicates its good diagnostic capability and provides a useful means to analyze protein biomarkers with low virus loads. Observation with transmission electron microscopy (TEM) provides direct evidence that the increase of hydrodynamic diameters resulted from the aggregation induced by immunological reactions. The bioassay also exhibits satisfactory specificity in analyzing HBsAg in serum media. Therefore, with its simple preparation, easy readout, and good stability, this bioassay has the potential to be developed into an automated and widely used biosensor assay.

A novel gold nanorods (GNRs) biosensor based on the localized surface plasmon resonance (LSPR) behavior was designed to detect the hepatitis B surface antigen (HBsAg) which indicates active viral replication of hepatitis B virus (HBV). The surface of GNRs was modified with monoclonal hepatitis B surface antibody (HBsAb) through physical adsorption. Raman spectrum, dynamic light scattering (DLS) and zeta potential measurement were conducted to access the nature of the GNRs after antibody modification. The binding of analyte to the molecular probe was monitored by the longitudinal wavelength shift of LSPR peak in the UV-Vis extinction spectrum resulting from the changes of local refractive index induced by the immunological reaction. The biosensor could be utilized in quantitative analysis in Tris buffers, which has dose-dependence response ranging from 0.01 IU/mL to 1 IU/mL. Further, the biosensor was suited for qualitative analysis of HBsAg in the actual media of blood serum and plasma. The ease of operation, high sensitivity, and its generality offer specific advantages over other GNRs-based immunoassay methods.

It remains challenging to detect unknown pathogenic bacteria in diagnostic, clinical and environmental fields. This work describes the approach to the development of a sensitive, broad-range genosensing assay targeting the conserved 16S rDNA region existing in most bacteria, by monitoring the aggregation level of gold nanorods (GNRs)-based nanoprobes through their localized surface plasmon resonance (LSPR) property. In the quantitative detection of artificial sequence, the limit of detection (LOD) of such a bioassay is demonstrated to reach the 5 pM level. This pair of universal GNRs-based nanoprobes can further identify at least 6 species of bacteria that were most prevalent in platelet concentrates (PCs) and have no cross-reaction with other pathogens. Moreover, it also exhibits higher sensitivity than other broad-range methods in analysing Serratia marcescens-spiked PCs. Therefore, the presented strategy not only provides a novel and effective DNA analysis method to detect multiple bacterial contaminations in PCs, but also opens up possibilities for its future use of detecting unknown bacteria in other systems, such as food and water, even at ultralow levels.

In the present study, we aimed to develop a nucleic acid lateral-flow method for the rapid and sensitive detection of multiple bacteria that contaminate platelet concentrations (PCs). Polymerase chain reaction (PCR) amplicons were produced by a set of board-range primers that recognize the conserved region of bacteria 16S rDNA, followed by hybridization with both an FITC (fluorescein isothiocyanate)-labelled probe and biotin-labelled probe, and then a nucleic acid lateral-flow dipstick (LFD) assay. The LFD accurately identified 7 species of bacteria, but had no cross-reactivity with human genomic DNA. The limit of detection (LOD) of the LFD assay was as low as 10(1) copies/µL of 16S rDNA for plasmid. In the case of spiked PCs without enrichment, the detection limit of LFD for K. pneumonia was 5 CFU/mL, 6.5 × 10(4) CFU/mL for the S. epidermidis and 35 CFU/mL for P. aeruginosa.

The identification and quantitative analysis of protein-protein interactions are essential to the functional characterization of proteins in the post-proteomics era. The methods currently available are generally time-consuming, technically complicated, insensitive and/or semi-quantitative. The lack of simple, sensitive approaches to precisely quantify protein-protein interactions still prevents our understanding of the functions of many proteins. Here, we develop a novel dual luciferase reporter pull-down assay by combining a biotinylated Firefly luciferase pull-down assay with a dual luciferase reporter assay. The biotinylated Firefly luciferase-tagged protein enables rapid and efficient isolation of a putative Renilla luciferase-tagged binding protein from a relatively small amount of sample. Both of these proteins can be quantitatively detected using the dual luciferase reporter assay system. Protein-protein interactions, including Fos-Jun located in the nucleus; MAVS-TRAF3 in cytoplasm; inducible IRF3 dimerization; viral protein-regulated interactions, such as MAVS-MAVS and MAVS-TRAF3; IRF3 dimerization; and protein interaction domain mapping, are studied using this novel assay system. Herein, we demonstrate that this dual luciferase reporter pull-down assay enables the quantification of the relative amounts of interacting proteins that bind to streptavidin-coupled beads for protein purification. This study provides a simple, rapid, sensitive, and efficient approach to identify and quantify relative protein-protein interactions. Importantly, the dual luciferase reporter pull-down method will facilitate the functional determination of proteins.