Mn(II) Optimized Sono/Chemodynamic Effect of Porphyrin-Metal-Organic Framework Nanosheets for MRI-Guided Colon Cancer Therapy and Metastasis Suppression

Sonodynamic therapy (SDT) offers a remarkable non-invasive ultrasound (US) treatment by activating sonosensitizer and generating reactive oxygen species (ROS) to inhibit tumor growth. The development of multifunctional, biocompatible, and highly effective sonosensitizers remains a current priority for SDT. Herein, the first report that Mn(II) ions chelated Gd-TCPP (GMT) nanosheets (NSs) are synthesized via a simple reflux method and encapsulated with pluronic F-127 to form novel sonosensitizers (GMTF). The GMTF NSs produce a high yield of ROS under US irradiation due to the decreased highest occupied molecular orbital-lowest unoccupied molecular orbital gap energy (2.7-1.28 eV). Moreover, Mn(II) ions endow GMTF with a fascinating Fenton-like activity to produce hydroxyl radicals in support of chemodynamic therapy (CDT). It is also effectively used in magnetic resonance imaging (MRI) with high relaxation rate (r 1: 4.401 mM-1 s-1) to track the accumulation of NSs in tumors. In vivo results indicate that the SDT and CDT in combination with programmed cell death protein 1 antibody (anti-PD-1) show effective metastasis prevention effects, and 70% of the mice in the GMTF + US + anti-PD-1 group survived for 60 days. In conclusion, this study develops a sonosensitizer with promising potential for utilizing both MRI-guided SDT and CDT strategies.

Bionic nanotheranostic for multimodal imaging-guided NIR-II-photothermal cancer therapy

In photothermal therapy (PTT), the photothermal conversion of the second near-infrared (NIR-II) window allows deeper penetration and higher laser irradiance and is considered a promising therapeutic strategy for deep tissues. Since cancer remains a leading cause of deaths worldwide, despite the numerous treatment options, we aimed to develop an improved bionic nanotheranostic for combined imaging and photothermal cancer therapy. We combined a gold nanobipyramid (Au NBP) as a photothermal agent and MnO2 as a magnetic resonance enhancer to produce core/shell structures (Au@MnO2; AM) and modified their surfaces with homologous cancer cell plasma membranes (PM) to enable tumour targeting. The performance of the resulting Au@MnO2@PM (AMP) nanotheranostic was evaluated in vitro and in vivo. AMP exhibits photothermal properties under NIR-II laser irradiation and has multimodal in vitro imaging functions. AMP enables the computed tomography (CT), photothermal imaging (PTI), and magnetic resonance imaging (MRI) of tumours. In particular, AMP exhibited a remarkable PTT effect on cancer cells in vitro and inhibited tumour cell growth under 1064 nm laser irradiation in vivo, with no significant systemic toxicity. This study achieved tumour therapy guided by multimodal imaging, thereby demonstrating a novel strategy for the use of bionic gold nanoparticles for tumour PTT under NIR-II laser irradiation.

Rational Design of Dynamically Super-Tough and Super-Stretchable Hydrogels for Deformable Energy Storage Devices

Hydrogels possess unique polymer networks that offer flexibility/stretchability, high ionic conductivity, and resistance to electrolyte leakage, making them suitable for deformable energy storage devices. Endowing the mechanical functionality of the hydrogel electrolytes focus on either enhancing the stretchability or the toughness. However, the stretchability and the toughness are generally a trade-off that the stretchable gels are intrinsically prone to damage and sensitive to notches and cracks. Here, the regulating strategies on the hydrogel's mechanical properties are provided to develop the designated hydrogel electrolyte, where different polymeric network structures are constructed, including single network structures, semi-interpenetrating network structures, and interpenetrating dual-network structures. A comprehensive comparison of these polymer network structures is conducted to evaluate their mechanical stretchability and toughness. Designing super-tough and super-stretchable hydrogels based on specific application requirements can be realized by striking a balance by regulating the hydrogel structure. In specific, incorporating semi-interpenetrating networks significantly can enhance stretchability to achieve a break elongation up to 1300%, while the interpenetrating dual-networks can largely improve the toughness to realize the extraordinary fracture toughness of 6.843 kJ m-2 . These findings offer valuable designing guidance for designated hydrogel electrolytes and the deformable zinc-silver battery is demonstrated with high mechanical stability and electrochemical performance.

Dual-targeting nanotheranostics for MRI-guided enhanced chemodynamic therapy of hepatoma via regulating the tumor microenvironment

Chemodynamic therapy (CDT), as a reactive oxygen species (ROS)-based therapeutic modality, has attracted much attention in recent years. However, the insufficient therapeutic effect of CDT is due to the antioxidant system in the tumor microenvironment, such as high levels of glutathione (GSH). In this study, we developed a biological/physical dual-targeting nanotheranostic agent (relaxation rate, r1: 6.3 mM-1 s-1 and r2: 13.11 mM-1 s-1) for enhanced CDT of SMCC-7721 tumors. This nanotheranostic agent is composed of a homologous tumor cell membrane (TCM), magnetic ferric oxide, and manganese oxide and is denoted as FM@TCM nanoparticles (NPs). A favorable effect of in vitro CDT on SMCC-7721 cells (IC50: 20 μg mL-1) is demonstrated, attributed to the Fenton reaction and oxidative stress resulting from the reduction of the GSH level. In vivo T1/T2 magnetic resonance imaging (MRI) confirms that the tumor accumulation of FM@TCM NPs is promoted by concurrent bioactive targeting of the homologous TCM and physico-magnetic targeting of tumor tissues with an external magnetic field. Impressive chemodynamic therapeutic effects on SMCC-7721 tumors are demonstrated through the catalysis of endogenous hydrogen peroxide and depletion of GSH to generate high levels of ROS. Dual-targeting FM@TCM NPs inhibit SMCC-7721 tumor growth (∼90.9%) in vivo without any biotoxicity. This nanotheranostic agent has great potential for use in MRI-guided CDT.

Compartmentalized Nano-MOFs as Co-delivery Systems for Enhanced Antitumor Therapy

Therapeutic bioactive macromolecules hold great promise in cancer therapy, but challenges such as low encapsulation efficiency and susceptibility to inactivation during the targeted co-delivery hinder their widespread applications. Compartmentalized nano-metal-organic frameworks (nMOFs) can easily load macromolecules in the innermost layer, protect them from the outside environment, and selectively release them in the target location after stimulation, showing great potential in the co-delivery of biomacromolecules. Herein, the rationally designed (GOx + CAT)/ZIF-8@BSATPZ/ZIF-8 (named GCZ@BTZ) nMOFs with compartmentalized structures are employed to deliver cascaded enzymes and the chemotherapeutic drug tirapazamine (TPZ)-conjugated bovine serum albumin (BSATPZ). Benefiting from the compartmentalized structure and protective shell, the GCZ@BTZ system is stable during blood circulation and preferentially accumulates in the tumor. Furthermore, in response to the acidic tumor environment, GCZ@BTZ effectively released the loading enzymes and BSATPZ. Along with the tumor starvation caused by depletion of glucose, cascaded reactions could also contribute to the enhancement of tumor hypoxia, which further activated BSATPZ-based chemotherapy. Notably, in the mouse tumor models, GCZ@BTZ treatment significantly inhibits tumor survival and metastasis. Such a compartmentalized nMOF delivery system presents a promising avenue for the efficient delivery of bioactive macromolecules.

Rapid controllable synthesis of branched Au superparticles: formation mechanism of toggling the growth mode and their applications in optical broadband absorption

We develop a tunable, ultrafast (5 seconds), and mass-producible seed-mediated synthesis method to prepare branched Au superparticles consisting of multiple small Au island-like nanoparticles by a wet chemical route. We reveal and confirm the toggling formation mechanism of Au superparticles between the Frank-van der Merwe (FM) growth mode and the Volmer-Weber (VW) growth mode. The key factor of this special structure is the frequent toggling between the FM (layer by layer) growth mode and the VW (island) growth mode induced by 3-aminophenol, which is continuously absorbed on the surface of newborn Au nanoparticles, leading to a relatively high surface energy during the overall synthesis process, thus achieving an island on island growth. Such Au superparticles demonstrate broadband absorption from visible to near-infrared regions due to their multiple plasmonic coupling and hence they have important applications in sensors, photothermal conversion and therapy, etc. We also exhibit the excellent properties of Au superparticles with different morphologies, such as NIR-II photothermal conversion and therapy and SERS detection. The photothermal conversion efficiency under 1064 nm laser irradiation was calculated to be as high as 62.6% and they exhibit robust photothermal therapy efficiency. This work provides insight into the growth mechanism of plasmonic superparticles and develops a broadband absorption material for highly efficient optical applications.

Gold nanobipyramid@copper sulfide nanotheranostics for image-guided NIR-II photo/chemodynamic cancer therapy with enhanced immune response

Photothermal therapy (PTT), photodynamic therapy (PDT), and chemodynamic therapy (CDT) can cause cancer cell death through an immunogenic process. However, the study of second near-infrared window (NIR-II)-triggered PTT and PDT combined with CDT to induce an immune response has not been recently reported. Here, we integrated gold nanobipyramids and copper sulfide in a core/shell architecture (AuNBP@CuS). The material displays both photodynamic and photothermal properties under irradiation with a NIR-II laser. The released Cu²⁺ from CuS under an acidic tumor microenvironment can be converted to Cu⁺ by glutathione following a Fenton-like reaction with hydrogen peroxide to generate highly toxic hydroxyl radicals in the tumor region. Both in vitro and in vivo results demonstrated that such multifunctional nanoplatforms could achieve enhanced efficiency for image-guided tumor suppression based on the NIR-II photo/chemodynamic therapy. We found that damage-associated molecular pattern molecules such as adenosine triphosphate, pre-apoptotic calreticulin, and high mobility group box-1 in dying cells induced by the NIR-II photo/chemodynamic therapy could simultaneously trigger adaptive immune responses. This is the first report revealing that NIR-II photo/chemodynamic therapy based on AuNBP@CuS had promising performance on tumor suppressor with an effective immunogenic cell death process. STATEMENT OF SIGNIFICANCE: 1. AuNBP@CuS displays both NIR-II photodynamic and photothermal properties. 2. Cu⁺ following a Fenton-like reaction to generate highly toxic hydroxyl radicals. 3. The NIR-II photo/chemodynamic therapy can trigger adaptive immune responses. 4. Such multifunctional nanoplatforms could achieve enhanced efficiency for tumor suppression.

Fe/MOF based platform for NIR laser induced efficient PDT/PTT of cancer

Introduction: Photodynamic therapy (PDT) and photothermal therapy (PTT) are widely used in the treatment of tumors. However, their application in the treatment of clinical tumors is limited by the complexity and irreversible hypoxia environment generated by tumor tissues. To overcome this limitation, a nanoparticle composed of indocyanine green (ICG) and Fe-MOF-5 was developed. Methods: We prepared F-I@FM5 and measured its morphology, particle size, and stability. Its enzyme like ability and optical effect was verified. Then we used MTT, staining and flow cytometry to evaluated the anti-tumor effect on EMT-6 cells in vitro. Finally, the anti-tumor effect in vivo has been studied on EMT-6 tumor bearing mice. Results: For the composite nanoparticle, we confirmed that Fe-MOF-5 has the best nanozyme activity. In addition, it has excellent photothermal conversion efficiency and generates reactive oxygen species (ROS) under near-infrared light irradiation (808 nm). The composite nanoparticle showed good tumor inhibition effect in vitro and in vivo, which was superior to the free ICG or Fe-MOF-5 alone. Besides, there was no obvious cytotoxicity in major organs within the effective therapeutic concentration. Discussion: Fe-MOF-5 has the function of simulating catalase, which can promote the decomposition of excessive H₂O₂ in the tumor microenvironment and produce oxygen to improve the hypoxic environment. The improvement of tumor hypoxia can enhance the efficacy of PDT and PTT. This research not only provides an efficient and stable anti-tumor nano platform, but also has broad application prospects in the field of tumor therapy, and provides a new idea for the application of MOF as an important carrier material in the field of photodynamic therapy.

Atom Absorption Energy Directed Symmetry-Breaking Synthesis of Au-Ag Hierarchical Nanostructures and Their Efficient Photothermal Conversion

Asymmetric plasmonic hierarchical nanostructures (HNs) are of great significance in optics, catalysis, and sensors, but the complex growth kinetics and lack of fine structure design limit their practical applications. Herein, a new atom absorption energy strategy is developed to achieve a series of Au-Ag HNs with the continuously tuned contact area in Janus and Ag island number/size on Au seeds. Different from the traditional passive growth mode, this strategy endows seed with a hand to capture the hetero atoms in a proactive manner, which is beyond the size, shape, and assembles of Au seed. Density functional theory reveals ththe adsorption of PDDA on Au surface leads to lower formation energy of Au-Ag bonds (-3.96 eV) than FSDNA modified Au surface (-2.44 eV). The competitive adsorption of two ligands on Au seed is the decisive factor for the formation of diverse Au-Ag HNs. In particular, the Au-Ag₂ HNs exhibit outstanding photothermal conversion capability in the near-infrared window, and in vivo experiments verify them as superior photothermal therapy agents. This work highlights the importance of the atom absorption energy strategy in unlocking the diversity of HNs and may push the synthesis and application of superstructures to a higher level.

In situ growing 3D-Cu coating to improve the reversibility and reaction kinetics of Zn metal anodes

The zinc metal anode is the most promising metal anode material in aqueous battery systems due to its low cost and high theoretical capacity. However, it still undergoes irreversible reactions such as premature failure of the dendrites/dead Zn during Zn stripping/plating, resulting in the inferior cycling stability of the Zn-based full cell. Here, we demonstrate a facile 3D-Cu alloy coating to improve Zn reversibility by providing spatial voids to accommodate the plated Zn to form dendrite-free morphology. Combining the larger 3D surface and the alloying–dealloying process, the Zn anode reactions exhibit enhanced reaction kinetics to meet large operating current densities. The 3D-Cu-coated Zn anode can deliver improved cycling stability for 350 h under a large areal capacity of 3 mAh cm⁻². It also enables MnO₂–Zn at the full cell level to achieve a specific capacity of 205 mAh g⁻¹ and longer cycling for 350 cycles with 87.4% retention of the initial capacity. This research provides a new pathway to achieve high reversible Zn metal chemistry.

All-In-One Second Near-Infrared Light-Responsive Drug Delivery System for Synergistic Chemo-Photothermal Therapy

Light-responsive nanocarrier-based drug delivery systems (NDDSs), due to their unique advantages such as safety, minimal cross-reaction, and spatiotemporal precision, have received wide attention. Notably, second near-infrared (NIR-II) light, which has a high penetration depth for manipulating NDDSs to release drugs, is in high demand. Herein, polyethylene glycol (PEG)-modified hollow Cu_xS nanoparticles (NPs) are developed as an all-in-one NIR-II light-responsive NDDS for synergistic chemo-photothermal therapy. First, Cu_xS-PEG NPs were prepared under mild conditions by using Cu₂O NPs as sacrificial templates. The morphology, photothermal effect, drug loading/releasing abilities, and synergistic chemo-photothermal therapy of Cu_xS-PEG NPs have been investigated. The Cu_xS-PEG NPs with hollow structures showed a high drug loading capacity (∼255 μg Dox per mg of Cu_xS NPs) and stimuli-responsive drug release triggered by NIR-II laser irradiation. The synergistic chemo-photothermal therapy based on the Dox/Cu_xS-PEG NPs showed 98.5% tumor elimination. Our study emphasizes the great potential of Cu_xS-PEG NPs as an all-in-one NIR-II light-responsive NDDS for applications in biomedicine.

Rational design of non-toxic GOx-based biocatalytic nanoreactor for multimodal synergistic therapy and tumor metastasis suppression

Rationale: Glucose oxidase (GOx)-based biocatalytic nanoreactors can cut off the energy supply of tumors for starvation therapy and deoxygenation-activated chemotherapy. However, these nanoreactors, including mesoporous silica, calcium phosphate, metal-organic framework, or polymer nanocarriers, cannot completely block the reaction of GOx with glucose in the blood, inducing systemic toxicity from hydrogen peroxide (H₂O₂) and anoxia. The low enzyme loading capacity can reduce systemic toxicity but limits its therapeutic effect. Here, we describe a real 'ON/OFF' intelligent nanoreactor with a core-shell structure (GOx + tirazapamine (TPZ))/ZIF-8@ZIF-8 modified with the red cell membrane (GTZ@Z-RBM) for cargo delivery.

Methods: GTZ@Z-RBM nanoparticles (NPs) were prepared by the co-precipitation and epitaxial growth process under mild conditions. The core-shell structure loaded with GOx and TPZ was characterized for hydrate particle size and surface charge. The GTZ@Z-RBM NPs morphology, drug, and GOx loading/releasing abilities, system toxicity, multimodal synergistic therapy, and tumor metastasis suppression were investigated. The in vitro and in vivo outcomes of GTZ@Z-RBM NPs were assessed in 4T1 breast cancer cells.

Results: GTZ@Z-RBM NPs could spatially isolate the enzyme from glucose in a physiological environment, reducing systemic toxicity. The fabricated nanoreactor with high enzyme loading capacity and good biocompatibility could deliver GOx and TPZ to the tumors, thereby exhausting glucose, generating H₂O₂, and aggravating hypoxic microenvironment for starvation therapy, DNA damage, and deoxygenation-activated chemotherapy. Significantly, the synergistic therapy effectively suppressed the breast cancer metastasis in mice and prolonged life without systemic toxicity. The in vitro and in vivo results provided evidence that our biomimetic nanoreactor had a powerful synergistic cascade effect in treating breast cancer.

Conclusion: GTZ@Z-RBM NPs can be used as an 'ON/OFF' intelligent nanoreactor to deliver GOx and TPZ for multimodal synergistic therapy and tumor metastasis suppression.

Rapid synthesis of monodispersed Au-Ag alloy nanosponges using selective laser melting and dealloying for sensitive near-infrared surface-enhanced Raman scattering

We developed a rapid synthesis method for monodispersed Au-Ag alloy nanosponges (NSs) with high density of 'hotspots' for near-infrared surface enhanced Raman scattering (NIR-SERS) by a selective laser-irradiation melting and chemical dealloying process. Au@Ag core-shell nanocubes were firstin situconverted into solid alloyed Au-Ag nanospheres by a rapid laser irradiation igniting quick fusion and quenching process within two minutes. The alloyed Au-Ag nanospheres transformed into Au-Ag alloy NSs after treated by a chemical dealloying process. Different from traditional thermal annealing, it thus can effectively avoid the heat fusion between nanoparticles, and maintain the alloyed Au-Ag nanospheres and NSs in high monodispersity. Importantly, due to the strong plasmonic coupling in nanopores (pore size less than 10 nm), the obtained Au-Ag alloy NSs show a broad and intense localized surface plasmon resonances absorption ranging from visible to near-Infrared region (500-1200 nm). The accessibly open structures for absorbing targets and high-density of 'NIR-hotspots' endow the Au-Ag alloy NSs substrate with superior sensitivity in NIR-SERS detection of 4-aminothiophenol with an enhancement factor of ∼10⁷. This work not only provides a simple pathway for rapid preparation of NIR-SERS substrate for biosensing, but also might open up a new horizon for fabricating spongy nanostructures with other elements.

Pre- and post-irradiation mild hyperthermia enabled by NIR-II for sensitizing radiotherapy

The clinical application of cancer radiotherapy is critically impeded by hypoxia-induced radioresistance, insufficient DNA damage, and multiple DNA repair mechanisms. Herein we demonstrate a dual-hyperthermia strategy to potentiate radiotherapy by relieving tumor hypoxia and preventing irradiation-induced DNA damage repair. The tumor hyperthermia temperature was well-controlled by a near infrared laser with minimal side effects using PEGylated nanobipyramids (PNBys) as the photo-transducer. PNBys have narrow longitudinal localized surface plasmon resonance peak in NIR-II window with a high extinction coefficient (2.0 × 10¹¹ M^-1 cm^-1) and an excellent photothermal conversion efficiency (44.2%). PNBys-induced mild hyperthermia (MHt) prior to radiotherapy enables vessel dilation, blood perfusion, and hypoxia relief, resulting in an increased susceptibility of tumor cells response to radiotherapy. On the other hand, MHt after radiotherapy inhibits the repair of DNA damage generated by irradiation. The PNBys exert hierarchically superior antitumor effects by the combination of MHt pre- and post-radiotherapy in murine mammary tumor EMT-6 model. Consequently, different from the simple combination of RT and MHt, the coupling of pre- and post-MHt with RT by PNBys open intriguing avenues towards new promising antitumor efficacy.

Dynamically Tunable Plasmonic Band for Reversible Colorimetric Sensors and Surface-Enhanced Raman Scattering Effect with Good Sensitivity and Stability

A colorimetric sensor based on plasmonic nanoparticles (NPs) is a promising and convenient detection tool, but its reproducibility and adjustability remain a challenge because the NPs are mainly random and uncontrollable. Herein, a colorimetric sensor with good reversibility and reproducibility was prepared by embedding the two-dimensional (2D) Au NP arrays on the surface of the polyacrylamide hydrogel film to form 2D Au NP arrays attached a hydrogel composite. For this composite, with the change of the interspacing distance of Au NPs driven by the swelling-shrinking behavior of the hydrogel carrier, the diffraction peaks faded away and plasmonic coupling peaks appeared, accompanied by a series of obvious color changes (iridescence ↔ violet ↔ golden yellow ↔ red), which can be correlated to the applied water content. Importantly, the composite had good reproducibility as a result of a highly ordered array structure. Additionally, this colorimetric sensor with a dynamically tunable plasmonic band can be used as a high-quality surface-enhanced Raman scattering (SERS) substrate because the gap distance of the Au NPs can be uniformly controlled. We demonstrated that, as the active gap distance decreased, the SERS signals can be significantly intensified. When the water content reached 40%, this SERS substrate exhibited high sensitivity (10^-10 M for 4-aminothiophenol and 10^-9 M for thiram) and good reproducibility (relative standard deviation of <20%) using the excitation laser of 785 nm because of the small gap between two adjacent Au NPs and the highly ordered periodic structure. Such 2D Au NP arrays attached to a hydrogel composite could be a new strategy to obtain a high-quality colorimetric sensor and dynamic SERS substrate.

Nanoplatforms with Remarkably Enhanced Absorption in the Second Biological Window for Effective Tumor Thermoradiotherapy

Thermoradiotherapy acts as an important antitumor modality because heating can increase the blood flow and improve the oxygen level in tumor, thus remission of hypoxia-associated resistance for radiotherapy (RT). However, most agents for thermoradiotherapy are used either in the first near-infrared biological window or low photothermal conversion efficiency. Here, a facile method to prepare Cu_xS/Au nanocomposites via reduction methods from Cu_xS templates in mild synthetic conditions (i.e., aqueous solution and room temperature) is presented. After the growth of Au nanoparticles, the Cu_xS/Au nanocomposites have greater benefits for photothermal efficiency than that of Cu_xS nanoparticles due to the enhanced absorbance in the second near-infrared window. Moreover, biocompatibility and stability of these nanocomposites are greatly improved by lipoic acid poly(ethylene glycol). After the tumors were irradiated with a 1064 nm laser, their oxygenation status is subsequently improved, and the combination of photothermal therapy and RT achieves remarkable synergistic therapeutic effects. This work provides a novel idea to design a new-generation nanomedicine for tumor thermoradiotherapy.

High vitamin levels ameliorate negative effect of rapeseed meal in meat ducks by improving antioxidant activity

The purpose of this study was to test the hypothesis that a high level of a vitamin premix would prevent the deleterious effects of rapeseed meal (RSM) when added to the diet of Pekin meat ducks. A total of 674 fifteen-day-old ducks were randomly allocated to 6 treatments with 7 cages of 16 ducks each. Three diets were formulated that contained 5, 10, or 20% RSM to compensate for reducing levels of soybean meal. Each RSM level diet was then supplemented with either a low level (low) or a high level (high) of a vitamin premix providing a total of 6 experimental diets. Ducks were fed one of the 6 experimental diets (N = 7 pens per diet) from days 15 to 35 at which time they were euthanized. Ducks were analyzed for antioxidant activity, liver biochemistry, thyroid hormone levels, and liver and thyroid histopathology. Addition of the high vitamin premixes to the 5 or 10% RSM diets improved BW (P < 0.05), BW gain (BWG; P < 0.05), and feed to gain ratio (F/G; P < 0.05) compared to the low vitamin premix; however, neither vitamin premix level had effects on production variables of ducks fed the 20% RSM diet. The high vitamin premix level also improved antioxidant capacity as evidenced by increased (P < 0.05) serum and liver superoxide dismutase activities over that of the low vitamin premix diets. Furthermore, the high level of vitamin premix prevented liver and thyroid pathologies in diets that contain RSM compared to diets with the low vitamin premix. These results suggested that high vitamin premix could prevent the negative effects of a 5 or 10% RSM diet in ducks by improving antioxidative capacities and alleviating liver and thyroid damage.

Au@Prussian Blue Hybrid Nanomaterial Synergy with a Chemotherapeutic Drug for Tumor Diagnosis and Chemodynamic Therapy

Recently, the chemodynamic therapy (CDT) has been widely reported and applied to tumor therapy. However, only low level hydroxyl radicals (^•OH) generated by the endogenous hydrogen peroxide alone are insufficient to kill the cancer cells. To overcome the insufficient therapeutic effect, this study reports a novel CDT based on Fenton catalyst Au@Prussian blue nanocubes (Au@PB NCs), subsequently encapsulated with doxorubicin (Dox). The in vitro and in vivo results indicate that the Dox-Au@PB NCs can take synergistic effects on tumor suppressor by CDT. In addition, Au@PB NCs possess high X-ray computed tomography contrast enhanced efficiency about ∼27.13 HU·mL·mg^-1. This study highlights a great potential of the Dox-Au@PB NCs for tumor diagnosis and CDT.

ROS-sensitive biomimetic nanocarriers modulate tumor hypoxia for synergistic photodynamic chemotherapy

The biomimetic NPs@i-RBM have the potential to overcome hypoxia-limited PDT, and significantly improve the anticancer efficacy by synergistic PDT and hypoxia-activated chemotherapy.

Periodic Porous Alloyed Au-Ag Nanosphere Arrays and Their Highly Sensitive SERS Performance with Good Reproducibility and High Density of Hotspots

Periodic porous alloyed Au-Ag nanosphere (NS) arrays with different periodic lengths and tunable composition ratios were prepared on Si substrates on a large scale (∼cm²) using stepwise metal deposition-annealing and subsequent chemical corrosion from a monolayer of colloidal polystyrene (PS) microspheres as the initial template. The porous alloyed Au-Ag NSs possessed a high porosity and bicontinuous morphology composed of hierarchically interconnected ligaments, which were obtained from an optimized dealloying process in nitric acid. Interestingly, when the dealloying time was prolonged, the average size of the porous alloyed NSs slightly decreased, and the width of the ligaments gradually increased. The periodic length of the array could be facilely changed by controlling the initial particle size of the PS template. Moreover, the porous alloyed Au-Ag NS arrays were explored as a platform for the surface-enhanced Raman scattering (SERS) detection of 4-aminothiophenol (4-ATP) and exhibited excellent reproducibility and high sensitivity because of the periodic structure of the arrays and the abundance of inherent "hotspots". After optimization experiments, a low concentration of 10^-10 M 4-ATP could be detected on these porous Au-Ag NS array substrates. Such highly reproducible SERS activity is meaningful for improving the practical application of portable Raman detection equipment.

Controlled synthesis of Cu nanoparticle arrays with surface enhanced Raman scattering effect performance

Herein, we report the synthesis of a 350 nm Cu nanoparticle array with different period combinations by a method based on a monolayer and have further investigated its surface-enhanced Raman scattering (SERS) properties experimentally.

Mo doped Ni2P nanowire arrays: an efficient electrocatalyst for the hydrogen evolution reaction with enhanced activity at all pH values

We report the successful synthesis of Mo doped Ni₂P nanowires (NWs) on a Ni foam (NF) substrate by a two-step strategy, which could be used as an efficient and stable hydrogen evolution reaction (HER) electrocatalyst over the whole pH range (0-14). Electrochemical investigations demonstrated that Mo doping made the catalytic activity of Ni₂P significantly enhanced. To achieve a current density of 10 mA cm^-2, Mo-Ni₂P NWs/NF required an overpotential of 67 mV in acidic solution, 78 mV in alkaline solution and 84 mV in neutral solution. It also showed superior stability with negligible activity decay after its use in the HER under different pH conditions for 24 h. Such excellent HER activity might originate from the synergistic effect between molybdenum (Mo) and nickel (Ni) atoms. The present work provides a valuable route for the design and synthesis of inexpensive and efficient all-pH HER electrocatalysts.

Optical sensing properties of Au nanoparticle/hydrogel composite microbeads using droplet microfluidics

Uniform Au nanoparticle (NP)/poly (acrylamide-co-acrylic acid) [P(AAm-co-AA)] hydrogel microbeads were successfully prepared using droplet microfluidics technology. The microbeads exhibited a good stimuli-responsive behavior to pH value. Particularly in the pH value ranging from pH 2-pH 9, the composite microbead sizes gradually increased along with the increase of pH value. The homogeneous Au NPs, which were encapsulated in the P(AAm-co-AA) hydrogel microbeads, could transform the volume changes of hydrogel into optical signals by a tested single microbead with a microspectrometre system. The glucose was translated into gluconic acid by glucose oxidase. Thus, the Au NP/P(AAm-co-AA) hydrogel microbeads were used for detecting glucose based on pH effects on the composite microbeads. For this, the single Au NP/P(AAm-co-AA) hydrogel microbead could act as a good pH- or glucose-visualizing sensor.

Rapid and Efficient Self-Assembly of Au@ZnO Core-Shell Nanoparticle Arrays with an Enhanced and Tunable Plasmonic Absorption for Photoelectrochemical Hydrogen Generation

High-quality Au@ZnO core-shell nanoparticle (NP) array films were easily and efficiently fabricated through an air/water interfacial self-assembly. These materials have remarkable visible light absorption capacity and fascinating performance in photoelectrochemical (PEC) water splitting with a photocurrent density of ∼3.08 mA/cm² at 0.4 V, which is superior to most ZnO-based photoelectrodes in studies. Additionally, the interesting PEC performance could be effectively adjusted by altering the thickness of the ZnO shell and/or the layer number of the array films. Results indicated that the bilayer film based on Au@ZnO NPs with 25 nm shell thickness displayed optimal behavior. The remarkable PEC capability could be ascribed to the enhanced light-harvesting ability of the Au@ZnO structured NPs by the SPR effect and the optimum film thickness. This work demonstrates a desirable paradigm for preparing photoelectrodes based on the synergistic effect of plasmatic NPs as the core and a visible optical absorbent and semiconductor as the shell. Moreover, this work provides a new approach for fabricating optoelectronic anode thin film devices through a self-assembly method.

Effective SERS-active substrates composed of hierarchical micro/nanostructured arrays based on reactive ion etching and colloidal masks

A facile route has been proposed for the fabrication of morphology-controlled periodic SiO2 hierarchical micro/nanostructured arrays by reactive ion etching (RIE) using monolayer colloidal crystals as masks. By effectively controlling the experimental conditions of RIE, the morphology of a periodic SiO2 hierarchical micro/nanostructured array could be tuned from a dome-shaped one to a circular truncated cone, and finally to a circular cone. After coating a silver thin layer, these periodic micro/nanostructured arrays were used as surface-enhanced Raman scattering (SERS)-active substrates and demonstrated obvious SERS signals of 4-Aminothiophenol (4-ATP). In addition, the circular cone arrays displayed better SERS enhancement than those of the dome-shaped and circular truncated cone arrays due to the rougher surface caused by physical bombardment. After optimization of the circular cone arrays with different periodicities, an array with the periodicity of 350 nm exhibits much stronger SERS enhancement and possesses a low detection limit of 10(-10) M 4-ATP. This offers a practical platform to conveniently prepare SERS-active substrates.

A novel process to prepare a thin silica shell on the PDDA-stabilized spherical Au nanoparticles assisted by UV light irradiation

The monodispersed PDDA-stabilized Au nanospheres can be coated with a thin silica shell assisted by UV light irradiation.

Effect of clopidogrel with or without omeprazole in patients with carotid artery stenting

BACKGROUND

Recent concerns have been raised about the potential for proton pump inhibitors (PPIs) to blunt the efficacy of clopidogrel. We observed the effect of clopidogrel plus aspirin with or without omeprazole in patients with carotid stenoses after they received placement of carotid stents.

METHODS

Sixty-four consecutive patients treated with percutaneous carotid artery stenting (CAS) comprised the sample. All enrolled patients underwent the C13 urea breath test (C13 UBT) before CAS. Patients with Helicobacter pylori infection and a history of peptic ulcer were assigned dual antiplatelet combination with omeprazole. Others received dual antiplatelet without omeprazole. Transcranial Doppler and ultrasonography were performed to assess the middle cerebral artery and carotid artery in follow-up at three months and six months.

RESULTS

Eight patients had gastrointestinal bleeding; the event rate was 22.6% without omeprazole and 3.8% with omeprazole. The rate of gastrointestinal bleeding was reduced with omeprazole as compared without omeprazole (p = 0.026, p < 0.05). The two groups did not differ significantly in the rate of in-stent restenosis and thrombus through transcranial Doppler and ultrasonography.

CONCLUSION

Among patients receiving dual antiplatelet therapy, prophylactic use of omeprazole reduced the rate of upper gastrointestinal bleeding. There was no apparent interaction between clopidogrel and omeprazole in patients with carotid artery stenting.

The 'innate' host response protects and damages the infected urinary tract

Symptoms of infection and tissue pathology are caused by the host response; not by the microbe per se. The same response is also critical for the defence and is needed to clear infection. It is therefore essential to understand how the host response is activated and to identify the critical effector mechanisms of the defence. We have studied these issues in the urinary tract infection (UTI) model. The symptoms of UTI and the host defence both rely on the so-called 'innate' immune system, making this one of the best characterized human disease models of 'innate immunity. We discuss the critical molecular events that determine whether the host response will be activated by P-fimbriated uropathogenic Escherichia coli as well as factors determining whether the patient develops acute pyelonephritis or asymptomatic bacteriuria. We will describe the glycoconjugate receptors used by the P-fimbriated bacteria adhering to host tissues, the recruitment of TLR4 co-receptors and the signalling pathways that allow progression to symptomatic disease, and discuss how these mechanisms are altered in asymptomatic carriers, presenting the possible genetic basis for unresponsiveness. We have shown that neutrophils are the critical effectors of the host defence and that neutrophil dysfunctions lead to acute pyelonephritis and renal scarring. Here we discuss the mechanisms of neutrophil-mediated, chemokine receptor (CXCR1)-dependent clearance, and the defect in interleukin-8 receptor homolog knock-out (IL-8Rh KO) mice and describe the data linking low CXCR1 expression to recurrent pyelonephritis in man, as well as the information on the genetic basis for low CXCR1 expression in affected patients. Finally, the mechanisms of renal scarring in IL8Rh KO mice will be discussed in relation to human disease. Our studies hold the promise to provide a molecular and genetic explanation for disease susceptibility in some patients with UTI and to offer more precise tools for the diagnosis and therapy of these infections.

Neutrophil recruitment, chemokine receptors, and resistance to mucosal infection

Neutrophil migration to infected mucosal sites involves a series of complex interactions with molecules in the lamina propria and at the epithelial barrier. Much attention has focussed on the vascular compartment and endothelial cells, but less is known about the molecular determinants of neutrophil behavior in the periphery. We have studied urinary tract infections (UTIs) to determine the events that initiate neutrophil recruitment and interactions of the recruited neutrophils with the mucosal barrier. Bacteria activate a chemokine response in uroepithelial cells, and the chemokine repertoire depends on the bacterial virulence factors and on the specific signaling pathways that they activate. In addition, epithelial chemokine receptor expression is enhanced. Interleukin (IL)-8 and CXCR1 direct neutrophil migration across the epithelial barrier into the lumen. Indeed, mIL-8Rh knockout mice showed impaired transepithelial neutrophil migration, with tissue accumulation of neutrophils, and these mice developed renal scarring. They had a defective antibacterial defense and developed acute pyelonephritis with bacteremia. Low CXCR1 expression was also detected in children with acute pyelonephritis. These results demonstrate that chemokines and chemokine receptors are essential to orchestrate a functional antimicrobial defense of the urinary tract mucosa. Mutational inactivation of the IL-8R caused both acute disease and chronic tissue damage.

P-fimbriae trigger mucosal responses to Escherichia coli in the human urinary tract

Uropathogenic Escherichia coli elicit a host response that determines the severity of urinary tract infection (UTI). Specific adherence mechanisms allow the bacteria to initiate this process by targeting epithelial cells in the urinary tract mucosa. Epidemiological studies show a strong association of P-fimbriae with disease severity, suggesting that adherence mediated by these organelles has a direct effect on mucosal inflammation in vivo. The present study examined the ability of P-fimbriae to induce inflammation in the human urinary tract. Patients were subjected to intravesical inoculation with a non-fimbriated E. coli strain or transformants of this strain expressing P-fimbriae. The inflammatory response was analysed as a function of P-fimbrial expression. The P-fimbriated transformants invariably caused higher interleukin (IL)-8, IL-6 and neutrophil responses in the urinary tract than the ABU strain. Furthermore, loss of P-fimbrial expression in vivo was accompanied by a return to background levels of neutrophils, IL-6 and IL-8 in individual patients. The results demonstrate that the pap sequences confer on a non-fimbriated, avirulent strain the ability to induce a host response in the human urinary tract. P-fimbriae thus fulfil the 'molecular Koch-Henle postulates' linking a single virulence factor to host response induction.

Type 1 fimbriae deliver an LPS- and TLR4-dependent activation signal to CD14-negative cells

Fimbriae target bacteria to different mucosal surfaces and enhance the inflammatory response at these sites. Inflammation may be triggered by the fimbriae themselves or by fimbriae-dependent delivery of other host activating molecules such as lipopolysaccharide (LPS). Although LPS activates systemic inflammation through the CD14 and Toll-like receptor 4 (TLR4) pathways, mechanisms of epithelial cell activation by LPS are not well understood. These cells lack CD14 receptors and are unresponsive to pure LPS, but fimbriated Escherichia coli overcome this refractoriness and trigger epithelial cytokine responses. We now show that type 1 fimbriae can present an LPS- and TLR4-dependent signal to the CD14-negative epithelial cells. Human uroepithelial cells were shown to express TLR4, and type 1 fimbriated E. coli strains triggered an LPS-dependent response in those cells. A similar LPS- and fimbriae-dependent response was observed in the urinary tract of TLR4-proficient mice, but not in TLR4-defective mice. The moderate inflammatory response in the TLR4-defective mice was fimbriae dependent but LPS independent. The results demonstrate that type 1 fimbriae present LPS to CD14-negative cells and that the TLR4 genotype determines this response despite the absence of CD14 on the target cells. The results illustrate how the host "sees" LPS and other microbial products not as purified molecules but as complexes, and that fimbriae determine the molecular context in which LPS is presented to host cells.

Interleukin-8 receptor knockout mice have subepithelial neutrophil entrapment and renal scarring following acute pyelonephritis

Interleukin (IL)-8 receptor knockout (KO) mice were shown to have a dysfunctional neutrophil response to urinary tract infection and to develop renal scarring. Intravesical Escherichia coli infection stimulated epithelial chemokine secretion and IL-8 receptor expression in control mice. Neutrophils migrated through the tissues and crossed the epithelial barrier into the urinary tract lumen. In murine IL-8 receptor homologue (mIL-8Rh) KO mice, infection triggered a chemokine response, and neutrophils were recruited but failed to traverse the mucosal barrier and accumulated under the epithelium. After 7 days, control mice were healthy, and infection was cleared, but mIL-8Rh KO mice had swollen kidneys, with neutrophil abscesses and high numbers of bacteria. After 35 days, they developed kidney pathology and renal scarring. The results demonstrate that chemokine receptors drive transepithelial neutrophil migration. In their absence, the neutrophils are trapped, and the tissues are destroyed. This molecular deficiency may determine the progression from acute pyelonephritis to renal scarring.

Transepithelial neutrophil migration is CXCR1 dependent in vitro and is defective in IL-8 receptor knockout mice

Neutrophil migration across infected mucosal surfaces is chemokine dependent, but the role of chemokine receptors has not been investigated. In this study, chemokine receptors were shown to be expressed by epithelial cells lining the urinary tract, and to play an essential role for neutrophil migration across the mucosal barrier. Uroepithelial CXCR1 and CXCR2 expression was detected in human urinary tract biopsies, and in vitro infection of human uroepithelial cell lines caused a dramatic increase in both receptors. As a consequence, there was higher binding of IL-8 to the cells and the IL-8-dependent neutrophil migration across the infected epithelial cell layers was enhanced. Abs to IL-8 or to the CXCR1 receptor inhibited this increase by 60% (p<0.004), but anti-CXCR2 Abs had no effect, suggesting that CXCR1 was the more essential receptor in this process. Similar observations were made in the mouse urinary tract, where experimental infection stimulated epithelial expression of the murine IL-8 receptor, followed by a rapid flux of neutrophils into the lumen. IL-8 receptor knockout mice, in contrast, failed to express the receptor, their neutrophils were unable to cross the epithelial barrier, and accumulated in massive numbers in the tissues. These results demonstrate that epithelial cells express CXC receptors and that infection increases receptor expression. Furthermore, we show that CXCR1 is required for neutrophil migration across infected epithelial cell layers in vitro, and that the murine IL-8 receptor is needed for neutrophils to cross the infected mucosa of the urinary tract in vivo.

Interleukin 8 receptor deficiency confers susceptibility to acute experimental pyelonephritis and may have a human counterpart

Neutrophils migrate to infected mucosal sites that they protect against invading pathogens. Their interaction with the epithelial barrier is controlled by CXC chemokines and by their receptors. This study examined the change in susceptibility to urinary tract infection (UTI) after deletion of the murine interleukin 8 receptor homologue (mIL-8Rh). Experimental UTIs in control mice stimulated an epithelial chemokine response and increased chemokine receptor expression. Neutrophils migrated through the tissues to the epithelial barrier that they crossed into the lumen, and the mice developed pyuria. In mIL-8Rh knockout (KO) mice, the chemokine response was intact, but the epithelial cells failed to express IL-8R, and neutrophils accumulated in the tissues. The KO mice were unable to clear bacteria from kidneys and bladders and developed bacteremia and symptoms of systemic disease, but control mice were fully resistant to infection. The experimental UTI model demonstrated that IL-8R-dependent mechanisms control the urinary tract defense, and that neutrophils are essential host effector cells. Patients prone to acute pyelonephritis also showed low CXC chemokine receptor 1 expression compared with age-matched controls, suggesting that chemokine receptor expression may also influence the susceptibility to UTIs in humans. The results provide a first molecular clue to disease susceptibility of patients prone to acute pyelonephritis.

Neutrophil recruitment and resistance to urinary tract infection

This study examined the role of neutrophil leukocytes for the antibacterial defense at mucosal infection sites. Urinary tract infection (UTI) was established by injection into the bladder lumen of Escherichia coli 1177, a fully virulent clinical isolate. Infection of C3H/HeN (lpsn, lpsn) mice recruited neutrophils into the urinary tract, and bacteria were cleared from kidneys and bladders. The neutrophil response was absent in C3H/HeJ (lpsd, lpsd) mice, and bacteria persisted in the tissues. Peripheral neutrophil depletion of C3H/HeN mice was subsequently achieved by pretreatment with the granulocyte-specific antibody RB6-8C5. The E. coli-induced neutrophil recruitment was inhibited, as shown by immunohistochemistry and tissue myeloperoxidase quantitation. As a consequence, bacterial clearance from kidneys and bladders was drastically impaired. Antibody treatment of C3H/HeJ mice had only a marginal effect. The results show that neutrophils are essential for bacterial clearance from the urinary tract and that the neutrophil recruitment deficiency in C3H/HeJ mice explains their susceptibility to gram-negative UTI.

P fimbriae-dependent, lipopolysaccharide-independent activation of epithelial cytokine responses

Cells in the mucosal barrier are equipped to sense and respond to microbes in the lumen and translate this molecular information into signals that can reach local or distant sites. The interaction of P-fimbriated Escherichia coli with human uroepithelial cells is a model to study the molecular mechanism of epithelial cell activation by mucosal pathogens. Here, we examine the role of lipopolysaccharide (LPS) as a co-stimulatory molecule in epithelial cell activation by P-fimbriated E. coli. P-fimbriated clinical isolates or recombinant strains were shown to trigger a fimbriae-dependent epithelial cell cytokine response. Mutational inactivation of the msbB sequences that control lipid A myristoylation drastically impaired monocyte stimulation but not epithelial responses to P-fimbriated bacteria. Polymyxin B or bactericidal/permeability increasing factor (BPI) neutralized the effects of lipid A in the monocyte assay, but did not reduce epithelial responses. Finally, isolated LPS of the smooth, rough and deep rough chemotypes were poor epithelial cell activators. The cells were shown to lack surface CD14 or CD14 mRNA as well as the CD14 co-receptor function and were also very poor LPS responders in the presence of human serum. These results demonstrate that epithelial cell responses to P-fimbriated E. coli are CD14 and LPS independent, and suggest that attaching pathogens can overcome the LPS unresponsiveness of epithelial cells by fimbriae-dependent activation mechanisms.

Macrophage inflammatory protein-2 is required for neutrophil passage across the epithelial barrier of the infected urinary tract

IL-8 is a major human neutrophil chemoattractant at mucosal infection sites. This study examined the C-X-C chemokine response to mucosal infection, and, specifically, the role of macrophage inflammatory protein (MIP)-2, one of the mouse IL-8 equivalents, for neutrophil-epithelial interactions. Following intravesical Escherichia coli infection, several C-X-C chemokines were secreted into the urine, but only MIP-2 concentrations correlated to neutrophil numbers. Tissue quantitation demonstrated that kidney MIP-2 production was triggered by infection, and immunohistochemistry identified the kidney epithelium as a main source of MIP-2. Treatment with anti-MIP-2 Ab reduced the urine neutrophil numbers, but the mice had normal tissue neutrophil levels. By immunohistochemistry, the neutrophils were found in aggregates under the pelvic epithelium, but in control mice the neutrophils crossed the urothelium into the urine. The results demonstrate that different chemokines direct neutrophil migration from the bloodstream to the lamina propria and across the epithelium and that MIP-2 serves the latter function. These findings suggest that neutrophils cross epithelial cell barriers in a highly regulated manner in response to chemokines elaborated at this site. This is yet another mechanism that defines the mucosal compartment and differentiates the local from the systemic host response.

Cytokine repertoire of epithelial cells lining the human urinary tract

PURPOSE

To examine the cytokine profile of epithelial cells lining the human urinary tract with the aim of differentiating between the constitutive and disease-related cytokine production in these tissues.

MATERIALS AND METHODS

Sections from the renal pelvis, ureter, bladder or urethra were obtained from 22 patients undergoing urinary tract surgery and were stained with monoclonal antibodies to interleukin(IL)-1beta, IL-4, IL-6, IL-8, interferon gamma (IFNgamma) and transforming growth factor beta (TGFbeta). Sections were classified according to the presence or absence of disease in the tissue.

RESULTS

Epithelial cells lining the renal pelvis, ureter, bladder or urethra all stained for IL-8 and TGFbeta (100%) in disease-free tissues and sections with cancer or interstitial cystitis (IC). In contrast, staining for IL-1beta, IL-4, IL-6 and IFNgamma varied with the disease state of the patient. Epithelial IL-1beta staining was absent (0%) in sections from healthy bladder, but positive in tissues with IC or cancer-associated pathology (50 to 100%). IL-6 staining was detected in the epithelial layer of several patients with IC or cancer related pathology, but only in cells with non-epithelial morphology and not in disease-free tissues. IFNgamma and IL-4 staining were only observed in patients with IC and only in cells with non-epithelial morphology.

CONCLUSIONS

The results show that epithelial cells from all parts of the urinary tract constitutively produce IL-8 and TGFbeta and suggest that the production of other cytokines varies with the disease of the patient. Constitutive cytokine production provides the basis for a rapid host response, in the defense against mucosal attack by microbes or toxic agents.

Immunoregulatory cytokines modify Escherichia coli induced uroepithelial cell IL-6 and IL-8 responses

This study analysed the effects of immunoregulatory cytokines on uroepithelial cell cytokine responses. The A-498 human kidney cell line was treated with the interleukins IL-2, IL-4, IL-5, IL-10, IL-12, IL-13, interferon gamma (IFN-alpha) and transforming growth factor beta (TGF-beta 1). Secreted IL-6 and IL-8 were quantitated by enzyme-linked immunoabsorbent assay (ELISA) and bioassay; IL-6 and IL-8 mRNA species were quantitated by reverse transcriptase polymerase chain reaction (RT-PCR). IL-4, IL-13, IFN-gamma, and TGF-beta 1, but not IL-2, IL-5, IL-10 or IL-12, stimulated IL-6 secretion. At high concentrations, IL-4 and IL-13 stimulated low levels of IL-8 secretion. Immunoregulatory cytokines were analysed for their ability to modify the A-498 cells' IL-6 and IL-8 secretion in response to Escherichia coli. IL-5, IL-12, IL-13 and TGF-beta 1 additively enhanced the bacterially induced IL-6 secretion, but they did not affect IL-8 secretion. The strongest affects on uroepithelial cell IL-6 and IL-8 responses in the presence of bacteria were observed in conjunction with IL-4 and IFN-alpha. IL-4 induced IL-6 production in synergy with E. coli. IFN-alpha both enhanced and inhibited IL-6 and IL-8 responses in combination with E. coli, depending on the order of stimulant addition. The results demonstrate that immunoregulatory cytokines can modify the uroepithelial cell responses to bacteria in vitro. In this way, T cells may regulate the cytokine responses of uroepithelial and possibly other mucosal epithelial cells in vivo.

Determination of interleukin 6 in human urine and epithelial cell supernatants

Interleukin 6 (IL-6) is a cytokine with many biological functions. It is produced by different tissues in response to infection and is secreted into the local body fluids. The aim of this study was to find a suitable assay to measure IL-6 in human urine. IL-6 was quantitated by a bioassay and by immunoassays based on neutralizing or nonneutralizing antibodies. The effect of human urine on the quantitation of IL-6 by these assays was analyzed using pooled human urine with added recombinant or natural human IL-6. Urine was found to disturb the growth of the B9 cells. When fractions from gel-filtered human urine were tested, a fraction corresponding to a protein molecular weight range of 10,000-1,000 was found to have a strong inhibitory effect in the B9 assay. In contrast, the low molecular weight fractions containing salts and pigments were not found to disturb the assay. The inhibitory effect of urine was avoided by diluting the samples > 80 times (final dilution in the test plate) or by dialysis. Furthermore, we analyzed IL-6 in urine samples from patients with urinary tract infection and supernatants from epithelial cells stimulated with bacteria in vitro. The B9 assay and the immunoassay based on non-neutralizing anti-IL-6 antibodies were more sensitive than the immunoassays based on neutralizing antibodies. While most of the B9 activity in the urine samples and supernatants could be neutralized by anti-IL-6 antibodies, some samples contained unneutralizable activity. These components remain to be defined. The results demonstrate considerable variation between assays used to quantitate natural IL-6.

Autoimmune mice and stimulated normal mice make lambda 1 with increased V region diversity

Previous studies of the genetic bases of murine SLE have defined gene segments that encode the H chain and the kappa L chain of anti-DNA, anti-Sm, and anti-IgG autoantibodies. As a result of these studies, the genetic origins of autoantibody H chains and kappa L chains are better understood, but little remains known about the genetic bases of autoantibody lambda-chains. Thus, we have analyzed serologically the germ-line and somatic origins of lambda 1 L chains in antibodies of normal mice and in both antibodies and autoantibodies of autoimmune mice. This study finds an increased lambda 1 diversity in both Ag-stimulated mice and autoimmune mice. This study also finds that the lambda 1 L chains in antibodies of unstimulated normal mice have the gene segment-encoded variable region, V lambda 1. In contrast, additional genetic processes appear to make the lambda 1 V regions of antibodies in Ag-stimulated normal mice and the lambda 1 V regions of both antibodies and autoantibodies in autoimmune mice. The increased lambda 1 diversity that we found in both Ag-stimulated mice and autoimmune mice might be caused by mutational processes creating antibody diversities. Therefore, the same somatic processes might be able to make both antibody and autoantibody lambda 1 diversities.

Autoimmune mice and stimulated normal mice make lambda 1 with increased V region diversity

Previous studies of the genetic bases of murine SLE have defined gene segments that encode the H chain and the kappa L chain of anti-DNA, anti-Sm, and anti-IgG autoantibodies. As a result of these studies, the genetic origins of autoantibody H chains and kappa L chains are better understood, but little remains known about the genetic bases of autoantibody lambda-chains. Thus, we have analyzed serologically the germ-line and somatic origins of lambda 1 L chains in antibodies of normal mice and in both antibodies and autoantibodies of autoimmune mice. This study finds an increased lambda 1 diversity in both Ag-stimulated mice and autoimmune mice. This study also finds that the lambda 1 L chains in antibodies of unstimulated normal mice have the gene segment-encoded variable region, V lambda 1. In contrast, additional genetic processes appear to make the lambda 1 V regions of antibodies in Ag-stimulated normal mice and the lambda 1 V regions of both antibodies and autoantibodies in autoimmune mice. The increased lambda 1 diversity that we found in both Ag-stimulated mice and autoimmune mice might be caused by mutational processes creating antibody diversities. Therefore, the same somatic processes might be able to make both antibody and autoantibody lambda 1 diversities.

Lack of relationship between serum gp70 levels and the severity of systemic lupus erythematosus in MRL/l mice

In the MRL/l mouse, gp70 apparently plays a role as an autoantigen in the development of SLE. However, while gp70 may be an important pathogenetic element, it is not essential to MRL SLE, since elimination of most of the serum gp70 and virtually all of the immune complex gp70 from MRL/l-low gp70 congenic lines had no observable effect on the course or nature of the disease. Thus, while gp70 in the MRL/l mouse appears to be a convenient autoantigenic target when present in significant levels, in its absence the host appears capable of directing its aberrant immunologic responsiveness elsewhere with undiminished pathogenicity.