Structural Insights into the Stability and Recognition Mechanism of the Antiquinalphos Nanobody for the Detection of Quinalphos in Foods.

Nanobodies (Nbs) have great potential in immunoassays due to their exceptional physicochemical properties. With the immortal nature of Nbs and the ability to manipulate their structures using protein engineering, it will become increasingly valuable to understand what structural features of Nbs drive high stability, affinity, and selectivity. Here, we employed an anti-quinalphos Nb as a model to illustrate the structural basis of Nbs' distinctive physicochemical properties and the recognition mechanism. The results indicated that the Nb-11A-ligand complexes exhibit a "tunnel" binding mode formed by CDR1, CDR2, and FR3. The orientation and hydrophobicity of small ligands are the primary determinants of their diverse affinities to Nb-11A. In addition, the primary factors contributing to Nb-11A's limited stability at high temperatures and in organic solvents are the rearrangement of the hydrogen bonding network and the enlargement of the binding cavity. Importantly, Ala 97 and Ala 34 at the active cavity's bottom and Arg 29 and Leu 73 at its entrance play vital roles in hapten recognition, which were further confirmed by mutant Nb-F3. Thus, our findings contribute to a deeper understanding of the recognition and stability mechanisms of anti-hapten Nbs and shed new light on the rational design of novel haptens and directed evolution to produce high-performance antibodies.

Hybrid M13 bacteriophage-based vaccine platform for personalized cancer immunotherapy.

Although cancer vaccines exhibit great advances in the field of immunotherapy, developing an efficient vaccine platform for personalized tumor immunotherapy is still a major challenge. Here we demonstrate that a bioactive vaccine platform (HMP@Ag) fabricated with hybrid M13 phage and personal tumor antigens can facilitate delivery of antigens into lymph nodes and activate antigen-presenting cells (APCs) through the Toll-like receptor 9 (TLR9) signaling pathway, which boosts both innate and adaptive immune response. As an adjuvant platform, hybrid M13 phages can deliver various tumor-specific antigens through simple adsorption to support the current development of personalized vaccines for cancers. Notably, the HMP@Ag vaccine not only prevented the tumors, but also delayed the tumor growth in established (subcutaneous and orthotopic) and metastatic tumor-bearing models while synergy with immune checkpoint blockade (ICB) therapy. Moreover, HMP@Ag triggered a robust neoantigen-based specific immune response in tumor-specific mutation models. In a clinically relevant surgery model, using autologous cell membrane from primary tumors-based HMP@Ag cooperation with ICB dramatically inhibited the post-operation recurrence, and elicited a long-term immune memory effect simultaneously. These findings imply that the M13 phage represents a powerful tool to develop a bio-activated hybrid platform for personalized therapy.

Bioinspired nano-vaccine construction by antigen pre-degradation for boosting cancer personalized immunotherapy.

Cancer vaccines-based cancer immunotherapy has drawn widespread concern. However, insufficient cancer antigens and inefficient antigen presentation lead to low immune response rate, which greatly restrict the practical application of cancer vaccines. Here, inspired by intracellular proteasome-mediated protein degradation pathway, we report an antigen presentation simplification strategy by extracellular degradation of antigen proteins into peptides with proteolytic enzyme for improving the utilization of cancer antigens and arousing restricted cancer immunity. The pre-degraded antigen peptides are first validated to exhibit an increased capacity on antigen-presenting cell (APC) stimulation compared with proteins and still reserve antigen specificity and major histocompatibility complex (MHC) affinity. Furthermore, by coordinating the pre-degraded peptides with calcium phosphate nanoparticles (CaP), a CaP-peptide vaccine (CaP-Pep) is constructed, which is verified to induce an efficient personalized immune response in vivo for multi-model anti-cancer therapy. Notably, this bioinspired strategy based on extracellular enzymatic hydrolysis for vaccine construction is not only applicable for multiple types of cancers, but also shows great potential in expanding immunology fields and translational medicine.

A Strategy Based on the Enzyme-Catalyzed Polymerization Reaction of Asp-Phe-Tyr Tripeptide for Cancer Immunotherapy.

Immunotherapy has provided a promising strategy for the treatment of cancers. However, even in tumors with high antigen burdens, the systemic inhibition of the antigen presentation still greatly restricts the application of immunotherapy. Here, we construct a tumor protein-engineering system based on the functional tripeptide, Asp-Phe-Tyr (DFY), which can automatically collect and deliver immunogenetic tumor proteins from targeted cells to immune cells. Through a tyrosinase-catalyzed polymerization, the DFY tripeptide selectively accumulates in tyrosinase high-expressed melanoma cells. Then quinone-rich intermediates are covalently linked with tumor-specific proteins by Michael addition and form tumor protein-carried microfibers that could be engulfed by antigen-presenting cells and exhibited tumor antigenic properties for boosting immune effect. In melanoma cells with deficient antigen presentation, this system can successfully enrich and transport tumor antigen-containing proteins to immune cells. Furthermore, in the in vivo study on murine melanoma, the transdermal delivery of the DFY tripeptide suppressed the tumor growth and the postsurgery recurrence. Our findings provide an avenue for the regulation of the immune system on an organism by taking advantage of certain polymerization reactions by virtue of chemical biology.

An RGB-emitting molecular cocktail for the detection of bacterial fingerprints.

Accumulating evidence indicates that colonized microbes play a crucial role in regulating health and disease in the human body. Detecting microbes should be essential for understanding the relationship between microbes and diseases, as well as increasing our ability to detect diseases. Here, a combined metabolic labeling strategy was developed to identify different bacterial species and microbiota by the use of three different fluorescent metabolite derivatives emitting red, green, and blue (RGB) fluorescence. Upon co-incubation with microbes, these fluorescent metabolite derivatives are incorporated into bacteria, generating unique true-color fingerprints for different bacterial species and different microbiota. A portable spectrometer was also fabricated to automate the colorimetric analysis in combination with a smartphone to conveniently identify different bacterial species and microbiota. Herein, the effectiveness of this system was demonstrated by the identification of certain bacterial species and microbiota in mice with different diseases, such as skin infections and bacteremia. By analyzing the microbiota fingerprints of saliva samples from clinical patients and healthy people, this system was proved to precisely distinguish oral squamous cell carcinoma (OSCC, n = 29) samples from precancerous (n = 10) and healthy (n = 5) samples.

Controllable gelation of artificial extracellular matrix for altering mass transport and improving cancer therapies.

Global alterations in the metabolic network provide substances and energy to support tumor progression. To fuel these metabolic processes, extracellular matrix (ECM) plays a dominant role in supporting the mass transport and providing essential nutrients. Here, we report a fibrinogen and thrombin based coagulation system to construct an artificial ECM (aECM) for selectively cutting-off the tumor metabolic flux. Once a micro-wound is induced, a cascaded gelation of aECM can be triggered to besiege the tumor. Studies on cell behaviors and metabolomics reveal that aECM cuts off the mass transport and leads to a tumor specific starvation to inhibit tumor growth. In orthotopic and spontaneous murine tumor models, this physical barrier also hinders cancer cells from distant metastasis. The in vivo gelation provides an efficient approach to selectively alter the tumor mass transport. This strategy results in a 77% suppression of tumor growth. Most importantly, the gelation of aECM can be induced by clinical operations such as ultrasonic treatment, surgery or radiotherapy, implying this strategy is potential to be translated into a clinical combination regimen.

Enzyme Mimicking Based on the Natural Melanin Particles from Human Hair.

Natural enzymes are mainly composed by the protein part and metallic cofactor part, both of which work cooperatively to achieve high catalytic activity. Here, natural melanin particles (NMPs) were extracted from human hair and further bound with metal ions to mimic natural enzymes. The different metal-bound NMPs (M-NMPs) exhibited different enzyme-like activities with great promise in diverse biomedical applications. It was found that Fe-bound NMPs (Fe-NMPs) showed outstanding peroxidase (POD)-like activity that possessed potential in antibacterial applications, and Mn-bound NMPs (Mn-NMPs) displayed catalase (CAT)-like activity with a remarkable radiotherapy sensitization effect in cancer therapy. Besides, Cu-bound NMPs (Cu-NMPs) could serve as combined POD, superoxide dismutase (SOD), and CAT alternatives, which exhibited prominent reactive oxygen species (ROS) scavenging ability, revealing great potential in anti-inflammation. The versatile enzyme-like activities of M-NMPs derived from hair might give extensive perspective for designing biomedical materials and provide a promising tool in solving biomedical problems.

Photo-Powered Artificial Organelles for ATP Generation and Life-Sustainment.

Adenosine triphosphate (ATP) is the most important immediate energy source for driving intracellular biochemical reactions in nearly all life forms. Controllable generation of ATP in life is still an unrealized goal. Here, thylakoid fragments are recombined with lipid molecules to synthesize a synthetic/biological hybrid proteoliposome, named highly efficient life-support intracellular opto-driven system (HELIOS) for the generation of ATP. With red light irradiation, HELIOS can improve the intracellular ATP concentration to 1.38-2.45 times in various cell lines. Moreover, it is noticed that HELIOS-mediated ATP generation can comprehensively promote cell functions such as protein synthesis and insulin secretion. At organ and individual levels, it is also proved that HELIOS can rescue a mouse heart from myocardial infarction and sustain life of fasting zebrafish Danio rerio models. The photo-powered artificial organelle can deepen our understanding of metabolism and enable the development of optical therapy that targets intracellular energy supply.

Normalizing Tumor Microenvironment Based on Photosynthetic Abiotic/Biotic Nanoparticles.

Tumor hypoxia has attained the status of a core hallmark of cancer that globally affects the entire tumor phenotype. Reversing tumor hypoxia might offer alternative therapeutic opportunities for current anticancer therapies. In this research, a photosynthetic leaf-inspired abiotic/biotic nano-thylakoid (PLANT) system was designed by fusing the thylakoid membrane with synthetic nanoparticles for efficient O2 generation in vivo. Under 660 nm laser irradiation, the PLANT system exhibited intracellular O2 generation and the anaerobic respiration of the multicellular tumor spheroid was suppressed by PLANT as well. In vivo, it was found that PLANT could not only normalize the entire metabolic network but also adjust the abnormal structure and function of the tumor vasculature. It was demonstrated that PLANT could significantly enhance the efficacy of phototherapy or antiangiogenesis therapy. This facile approach for normalizing the tumor microenvironment will find great potential in tumor therapy.

Effect of piglitazone and metformin on retinol-binding protein-4 and adiponectin in patients with type 2 diabetes mellitus complicated with non-alcohol fatty acid liver diseases.

OBJECTIVE: To compare the effects of piglitazone and metformin on retinol-binding protein-4 (RBP-4) and adiponcetin (APN) in patients with type 2 diabetes mellitus (T2DM) complicated with Non alcohol fatty acid liver disease (NAFLD). METHODS: Totally 60 T2DM patients complicated with NAFLD were equally and randomly divided into pioglitazone group and metform group. The levels of biochemical indicators including body mass index (BMI), glucose hemoglobin A1C (GHbA1C), insulin resistance (HOMA-IR), fasting blood glucose (FBG), fasting insulin (FIns), and serum triglycerides (TG) as well as serum RBP-4 and APN level were measured pre-treatment and 12 weeks after treatments. RESULTS: After 12 weeks of treaments, BMI, FBG, HOMA-IR, GHbA1C, FIns, and TG decreased (all P<0.05) in both piglitazone group and metform group. APN increased (all P<0.05) in both groups. RBP-4 decreased (P<0.05) in piglitazone group. Compare with the metform group, the levels of RBP-4, FIns ,and HOMA-IR decreased and BMI increased in piglitazone group (P<0.05). CONCLUSION: Piglitazone is superior to metoform in decreasing RBP-4 level and HOMA-IR in patients with T2DM complicated with NAFLD.

Generation of transgene-free induced pluripotent stem cells with non-viral methods.

Induced pluripotent stem (iPS) cells were originally generated from mouse fibroblasts by enforced expression of Yamanaka factors (Oct3/4, Sox2, Klf4, and c-Myc). The technique was quickly reproduced with human fibroblasts or mesenchymal stem cells. Although having been showed therapeutic potential in animal models of sickle cell anemia and Parkinson's disease, iPS cells generated by viral methods do not suit all the clinical applications. Various non-viral methods have appeared in recent years for application of iPS cells in cell transplantation therapy. These methods mainly include DNA vector-based approaches, transfection of mRNA, and transduction of reprogramming proteins. This review summarized these non-viral methods and compare the advantages, disadvantages, efficiency, and safety of these methods.

Correlation of T lymphocyte subsets with blood glucose level and the first-phase insulin secretion in patients with type 2 diabetes mellitus.

OBJECTIVE: To explore the relationship between the T cell subsets and glucose level and first-phase insulin secretion function in patients with type 2 diabetes mellitus (T2DM). METHODS: We determined the oral glucose tolerance (OGTT), insulin release test(IRT), body mass index(BMI), glycohemoglobin A1c (HbA1c), T lymphocyte subsets (CD4(+),CD8(+)), and activity of natural kill(NK) cell and ⊿I(30)/⊿G(30) in 78 newly diagnosed T2DM patients, 60 impaired glucose tolerance (IGT) patients, and 60 normal controls. RESULTS: DM and IGT patients had significantly lower levels of CD4(+), CD4(+)/CD8(+)ratio, activity of NK cell, and ⊿I(30)/⊿G(30) and significantly higher levels of HbA1c and CD8(+)compared with normal controls(all P<0.05). Patients in DM group had significantly lower level of CD4(+),⊿I(30)/⊿G(30) and significantly higher levels of FBG and HbA1c compared with IGT group. There was no significant difference in terms of CD8(+), CD4(+)/CD8(+)ratio, and activity of NK cell between IGT and DM groups, whereas CD4(+) T cells were negatively correlated with FBG and HbA1c and positively with ⊿I(30)/⊿G(30) . Multiple regression stepwise analysis showed that CD4(+) was independently associated with HbA1c and ⊿I(30)/⊿G(30). CONCLUSION: T2DM patients tends to have disorders in cellular immunity, which is correlated with blood glucose level and the insulin secretion function.

[The epidemiological study of work-related musculoskeletal disorders and related factors among automobile assembly workers].

OBJECTIVE: To investigate the work-related musculoskeletal disorders among automobile assembly workers, to discusses the related risk factors and their relationship. METHOD: The selected 1508 automobile assembly workers from a north car manufacturing company were regarded as the study object. The hazard zone jobs checklist, Nordic musculoskeletal symptom questionnaire (NMQ) and pain questionnaire were used to perform the epidemiological cross-sectional and retrospective survey and study for the General status, awkward ergonomics factors and related influencing factors, and musculoskeletal disorders of workers. RESULTS: The predominant body sites of occurring WMSDs among automobile assembly workers were mainly low back, wrist, neck and shoulders, the predominant workshop section of occurring WMSDs were mostly concentrated in engine compartment, interior ornament, door cover, chassis and debugging section. The predominant body site of WMSDs among engine compartment and chassis section workers was low back, interior ornament workers were low back and wrist, door cover workers was wrist, chassis workers was low back, debugging workers were neck and low back. Neck musculoskeletal disorders had the trend with the increase of a body height; Smoking may increase the occurrence of musculoskeletal disorders. CONCLUSION: The WMSDs appears to be a serious ergonomic proble assem among automobile assembly workers, predominant occurring site of WMSDs is with different workshop section, its characteristics is quite obvious, probably related to its existing awkward work position or activities. The worker height and smoking habits may be important factors which affect musculoskeletal disorders happen.

Model AVSWAT apropos of simulating non-point source pollution in Taihu lake basin.

Accelerated eutrophication and nutrient loads in the lakes are of major concern for human health and environment. This study was undertaken for modeling the non-point source pollution of Taihu lake basin in eastern China. The SWAT model having an interface in ArcView GIS was employed. Model sensitive parameters related to hydrology and water quality were obtained by sensitivity analysis, and then calibrated and validated by comparing model predictions with field data. The GIS showed good potential for parameterization of hill-slopes, channels, and representative slope profiles for SWAT model simulations. In a monthly and daily time step, the model's Nash-Sutcliffe coefficient (E) and the coefficient of determination (R(2)) indicated that values of simulated runoff, NH(4)(+)-N and total phosphorus were acceptably closer to the measured data. Surface water parameters especially CN, Soil-AWC and ESCO were the most sensitive and had more recognition in the model. It is concluded that runoff carrying N and P nutrients from chemical fertilizer inputs in agricultural areas is the major contributor to NPSP in the lake basin. So, decrease in excessive use of N and P fertilizers and their synergism with organic manures is recommended that would significantly reduce nutrient pollution in the lake ecosystem.

[Studies on the chemical constituents of the leaves of Polygonum multiflorum].

OBJECTIVE: To study the chemical constituents of the leaves of Polygonum multiflorum. METHODS: The chemical constituents were extracted with water and separated by manifold chromatography technique, and their structures were determined by spectral analysis. RESULTS: Eleven compounds were isolated and identified as physcion (I), emodin (II), noreugenin (III), apigenin (IV), hyperoside (V), rutin (VI), vitexin (VII), 2,3,5 ,4'-tetrahydroxy-stibene-2-O-beta-D-glucoside (VIII), beta-amyrin (IX), beta-sitosterol (X), daucosterol( XI). CONCLUSION: Among these compounds, I - IV, VI - XI are isolated from the leaves of Polygonum multiflorum for the first time.

[Studies on chemical constituents from rattan of Polygonum multiflorum].

OBJECTIVE: To study on the chemical constituents from rattan of Polygonum multiflorum. METHODS: The chemical constituents were extracted with alcohol and were separated with manifold chromatography technique. Their structures were determined by spectral analysis. RESULTS: Thirteen compounds were isolated and identified as Chrysophanol(I), Physcion(II), Emodin(III), Aloeemodin(IV), Rhein(V), Physcion-8-O-beta-D-glucoside(VI), Emodin-8-O-beta-D-glucoside (VII),2,3,5,4'-Tetrahydroxy-stibene-2-O-beta-D-glucoside(VIII), Noreugenin(IX), Apigenin(X), Daucosterol(XI), beta-Sitosterol(XII), Stearic acid(XIII). CONCLUSION: Among these, compounds I, IV-VI, VIII-XI, XIII are isolated from rattan of Polygonum multiflorum for the first time.

[Effect of electroacupuncture on mitochondrial membrane potential and apoptosis in the cerebral cortex in rats with focal cerebral ischemia/reperfusion injury].

OBJECTIVE: To investigate the effect of electroacupuncture (EA) on mitochondrial membrane potential and neuronal apoptosis in the cerebral cortex of rats with focal cerebral ischemia/reperfusion (CI/R) injury. METHODS: Thirty-six male SD rats were uniformly randomized into sham operation (sham), CI/R and CI/R + EA groups. CI/R model was established by middle cerebral artery occlusion (MCAO) and reperfusion. EA (2/15 Hz, 1 mA) was applied to "Shuigou" (GV 26) and "Baihui" (GV 20) for 30 min after CI/R. The mitochondrial membrane potential and neuronal apoptosis in the cerebral cortex (fronto-parietal lobes) in each group were detected by flow cytometer (FCM). RESULTS: In comparison with sham group, the mitochondrial membrane potential of CI/R group decreased significantly (P<0.01), while compared with CI/R group, it increased remarkably in CI/R + EA group (P<0.01). The percentage of neuronal apoptosis in CI/R group was significantly higher than that in sham group (P<0.01), and that of CI/R + EA group was significantly lower than that of CI/R group (P<0.01). CONCLUSION: EA can alleviate CI/R injury partially by up-regulating the mitochondrial membrane potential, which may contribute to its effect in reducing cerebral neuronal apoptosis.