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Pecan has been widely recognized for its high phenolic content and related health benefits. Previous studies indicated that pecan consumption might be beneficial in treating type 2 diabetes mellitus (T2DM). The objective of this study was to investigate the enzyme inhibitory activities of pecan phenolic compounds (PPC) and the effect in starch hydrolysis by in vitro simulation digestion. PPC was extracted with a solvent mixture from pecan powder and freeze-dried. PPC was tested for the inhibitory effects on α-amylase and α-glucosidase via enzyme kinetics study. Static in vitro digestion trials were conducted to evaluate the effect of intake of PPC and pecan powder on starch digestion. PPC displayed a potent inhibition effect against α-amylase and α-glucosidase with IC 50 of 77.9 μg/mL and 9.02 μg/mL, respectively. Both PPC and pecan powder inhibited starch hydrolysis during in vitro digestion. However, the level of inhibition was lower than that from the catalytic kinetics study, and PPC exhibited a higher inhibition effect than pecan powder. The results confirmed the potential of PPC as a novel enzyme inhibitor for T2DM management. The information is helpful to promote the intake of pecan nuts for health-enhancing effects. • Pecan phenolic compounds (PPC) exhibited a potent inhibitory effect against α-amylase and α-glucosidase. • PPC significantly reduced starch digestion in an in vitro model. • Pecan powder exerted a limited inhibitory effect on starch digestion. • PPC could be used as a potential enzyme inhibitor to regulate blood glucose levels [ABSTRACT FROM AUTHOR]

Integrity and privacy are two important secure matrices in cyber security. Due to the limited resources and computing capability of the sensor nodes, it is challenging to simultaneously satisfy these two matrices for top-k querying in two-tiered sensor networks. To solve this problem, this paper proposes a weight-bind-based secure top-k query processing scheme (WBB-TQ), which utilises both the order-preserving symmetric encryption scheme (OPES) and the pairwise-key encryption technique to ensure data privacy in top-k querying. Since OPES can keep the size orders of the sensed data items unchanged before and after they are encrypted, the upper-layer storage nodes in the network can process top-k queries without knowing the exact values of the sensed data items. To guarantee the completeness of query results, we propose a novel method to establish chaining relationship among all the data items generated by each sensor node. By checking whether the relationship holds on not, Sink can find out whether adversaries drop and/or tamper with part or all of the qualified top-k data items in the query results. Theoretical analyses show that WBB-TQ can preserve data integrity and privacy of the top-k query results. Extensive simulation results further demonstrate that, WBB-TQ incurs very low computational and communication cost in securing top-k querying. [ABSTRACT FROM AUTHOR]

Ultrathin zinc phthalocyanine/graphene/BiVO4 heterojunctions have been successfully synthesized for efficient wide visible-light catalytic conversion of CO2 to CO with 14-time photoactivity improvement compared to the bare BiVO4 nanosheet, attributed to the strengthened Z-scheme charge transfer and separation by increasing the optimized amount of highly dispersed ZnPc via the pre-modified graphene-modulated assembly. [ABSTRACT FROM AUTHOR]

Cascade charge transfer was realized by a H‐bond linked zinc phthalocyanine/BiVO4 nanosheet (ZnPc/BVNS) composite, which subsequently works as an efficient wide‐visible‐light‐driven photocatalyst for converting CO2 into CO and CH4, as shown by product analysis and 13C isotopic measurement. The optimized ZnPc/BVNS nanocomposite exhibits a ca. 16‐fold enhancement in the quantum efficiency compared with the reported BiVO4 nanoparticles at the excitation of 520 nm with an assistance of 660 nm photons. Experimental and theoretical results show the exceptional activities are attributed to the rapid charge separation by a cascade Z‐scheme charge transfer mechanism formed by the dimension‐matched ultrathin (ca. 8 nm) heterojunction nanostructure. The central Zn2+ in ZnPc could accept the excited electrons from the ligand and then provide a catalytic function for CO2 reduction. This Z‐scheme is also feasible for other MPc, such as FePc and CoPc, together with BVNS. [ABSTRACT FROM AUTHOR]

Cascade charge transfer was realized by a H‐bond linked zinc phthalocyanine/BiVO4 nanosheet (ZnPc/BVNS) composite, which subsequently works as an efficient wide‐visible‐light‐driven photocatalyst for converting CO2 into CO and CH4, as shown by product analysis and 13C isotopic measurement. The optimized ZnPc/BVNS nanocomposite exhibits a ca. 16‐fold enhancement in the quantum efficiency compared with the reported BiVO4 nanoparticles at the excitation of 520 nm with an assistance of 660 nm photons. Experimental and theoretical results show the exceptional activities are attributed to the rapid charge separation by a cascade Z‐scheme charge transfer mechanism formed by the dimension‐matched ultrathin (ca. 8 nm) heterojunction nanostructure. The central Zn2+ in ZnPc could accept the excited electrons from the ligand and then provide a catalytic function for CO2 reduction. This Z‐scheme is also feasible for other MPc, such as FePc and CoPc, together with BVNS. [ABSTRACT FROM AUTHOR]

Targeting the adaptor protein (transforming growth factor-β (TGF-β)-activated protein kinase 1 (TAK1)-binding protein 1) (TAB1)-mediated non-canonical activation of p38α to limit ischemia/reperfusion (I/R) injury after an acute myocardial infarction seems to be attractive since TAB1/p38α interaction occurs specifically in very limited circumstances and possesses unique structural basis. However, so far no TAB1/p38α interaction inhibitor has been reported due to the limited knowledge about the interfaces. In this study, we sought to identify key amino acids essential for the unique mode of interaction with computer-guided molecular simulations and molecular docking. After validation of the predicted three-dimensional (3-D) structure of TAB1/p38α complex, we designed several peptides and evaluated whether they could block TAB1/p38α interaction with selectivity. We found that a cell-permeable peptide worked as a selective TAB1/p38α interaction inhibitor and decreased myocardial I/R injury. To our knowledge, this is the first TAB1/p38α interaction inhibitor.Molecular Therapy (2013); 21 9, 1668-1677. doi:10.1038/mt.2013.90 [ABSTRACT FROM AUTHOR]

Abstract: By binding to T cell Ig mucin-3 (Tim-3) expressed on different cells, galectin-9 (Gal-9) mediates two important functions, triggering T cell death and activating innate immune cells. The mechanisms by which ligation of the same molecule on different cell types mediates different effects are largely unclear. Gal-9 contains two carbohydrate recognition domains (CRD) in the N- and C-terminal regions (Gal-9-N and Gal-9-C). The N and C terminals of Gal-9 have been shown to have different activities in promoting T cell death. However, whether the differences between two domains account for its dual functions remains to be elucidated. Here we hypothesized that the different functions of Gal-9 in innate immunity and adaptive immunity are mediated by different domains. To test this, we created recombinant Gal-9 (Gal-9-NC) and homodimers containing either the NCRD (Gal-9-N) or the CCRD (Gal-9-C). All these Gal-9 constructs can activate dendritic cells (DCs) and induce T cell death. However, the Gal-9-C was much more potent than the Gal-9-N in inducing T cell death, while the Gal-9-N was much more effective in activating DCs by inducing much higher TNF-α and IL-6 production, greater phosphorylation of p38 and AKT. In both DC and T cells, Gal-9-N but not Gal-9-C stimulation resulted in markedly iκBα degradation. Finally, computer analyses suggested different patterns and affinities for the binding of the Gal-9-N and Gal-9-C to their receptor, Tim-3. Our data suggest that the N- and C-terminal CRDs of Gal-9 contribute differently to its ability to induce T cell death and to activate DCs. Further investigations on the underlying mechanisms will provide new insights into the biochemical basis for the multiple activities of Gal-9. [ABSTRACT FROM AUTHOR]

Ultrathin molecularly-dispersed nickel phthalocyanine/phosphate-functionalized BiVO 4 Z-scheme heterojunctions as efficient photocatalysts for wide-spectrum photocatalytic overall water splitting. [Display omitted] • Molecularly dispersed nickel phthalocyanines are assembled on phosphate-functionalized BiVO4 nanosheets (NiPc/PO-BVNS). • Ultrathin NiPc/PO-BVNS exhibits superior overall water splitting performance without noble-metal cocatalysts and sacrificial agents. • Excellent photoactivities are mainly ascribed to the accelerated Z-scheme charge separation between nearly molecule-layer NiPcs and PO-BVNS. • Created negative surface field via the functionalized phosphate groups could trap holes to promote the charge separation. • Well-defined NiPc units provide abundant single catalytic sites to greatly facilitate the H2-evolution reaction. Photocatalytic overall water splitting (OWS) is a promising route for sustainable production of hydrogen fuels. A grand challenge is developing efficient photocatalysts with extended light absorption, high charge separation and abundant catalytic sites. Here, we designed molecular nickel phthalocyanines on phosphate-functionalized bismuth vanadate nanosheets (NiPc/PO-BVNS) as ultrathin heterojunctions, targeting OWS without noble-metal cocatalysts or sacrificial agents. Optimal NiPc/PO-BVNS affords H 2 /O 2 evolution rates of 23.89/12.23 μmol g−1 h−1 with stoichiometric ratio under UV–vis irradiation, which reaches remarkable 50-fold enhancement over the benchmark g-C 3 N 4 /BVNS. The excellent photoactivities are ascribed to the novel Z-scheme charge separation between NiPc and PO-BVNS, where phosphates are proved to induce quasi-single-molecule-layer dispersion of NiPcs by H-bonding effect meanwhile create negative field to trap holes. Moreover, well-defined Ni2+–N 4 center of NiPc could function as the catalytic sites for H 2 evolution. This work diversifies the artificial photosynthesis systems with a facile strategy of constructing novel Z-scheme organic/inorganic heterojunctions. [ABSTRACT FROM AUTHOR]

Abstract: The extracellular cysteine-rich domains of ErbB2 receptors play important roles in ligand binding and receptor dimerization. The aim of the present study was to design a novel peptide exerting cytostatic effect toward ErbB2-overexpessing tumors based on one of the cysteine-rich domain (S1) of ErbB2. In order to create a stable molecule with unique structural and binding property, a chimeric molecule PL45 composed of ErbB2 S1 domain targeting peptide and the five stranded coiled coil domain from cartilage oligomeric matrix protein (COMP) was generated. PL45 was efficiently expressed in Escherichia coli and exhibited remarkable thermal and pH stability. It was capable of interfering with dimerization of ErbB2 and inhibiting the growth of ErbB2-overexpessing tumor cells in vitro and in vivo. The results provide evidence that the coiled coil structure can be used as a new scaffold to stabilize short peptides with potential application for anti-cancer immunotherapy and S1 domain of ErbB2 is a promising target for drug design. [Copyright &y& Elsevier]

Abstract: A novel murine IgM-type anti-human CD20 monoclonal antibody (mAb) 1–28 was prepared in our Lab, which can induce apoptosis and inhibit proliferation of Daudi and Raji cells. However, the efficacy of 1–28mAb in human cancer therapy is likely to be limited by human anti-mouse antibody responses. A chimeric antibody, C1–28, containing 1–28mAb variable region genes fused to human constant region genes (gamma 1, kappa) was constructed. However, C1–28 lost the antigen-binding activity. Here, using sequence similarity and known 3D structure of antibody variable regions as template, the spatial conformations of 1–28 variable regions (i.e. VH and VL) were analyzed with computer-guided homology modeling methods. According to the surface electrostatic distribution and interaction free energy analysis, the relationship between structure and stability of 1–28 variable regions was studied theoretically and a new chimeric anti-CD20 antibody scFv-Ig named 5S was designed. Expression level of 5S in the culture supernatant was determined to be around 50μg/mL using sandwich ELISA method with chimeric antibody Rituxan as reference. 5S retained its murine counterpart''s binding activity by fluorescence-activated cell-sorting analysis. Furthermore, it could kill CD20 positive Daudi and Raji cells by complement-dependent cytotoxicity. For binding affinity often decreased even lost when IgM antibody was constructed into chimeric IgG1 form, our success give a hint about how to construct a IgG1-type chimeric antibody from IgM-type murine antibody to preserve its binding activity. [Copyright &y& Elsevier]

Abstract: Neutralizing of TNF-α has been proved effective in treatment of some autoimmune diseases, e.g. rheumatoid arthritis and Crohn''s disease. Low molecular weight synthetic peptides can mimic the binding sites of TNF-α receptors and block the activity of TNF-α. In order to stabilize the conformation, increase the affinity and bioactivity, in this study, heavy chain variable region of human antibody was used as a scaffold to simultaneously display three peptides, which were designed on the interaction between TNF-α and it''s neutralizing monoclonal antibody. On the basis of the structural character and physical–chemical property of the families of seven kinds of heavy chain variable regions (VH) in human antibodies, the fifth type of VH was screened as scaffold to display the antagonist peptide. Based on the computer-guided molecular design method, a novel domain antibody against TNF-α (named as ATD5) was designed as TNF-α antagonist. The theoretical study showed that ATD5 was more stable than displayed antagonist peptide. The binding activity with TNF-α was higher than free peptides. After expression and purification in Escherichia coli, ATD5 could bind directly with TNF-α and inhibit the binding of TNF-α to its two receptors, TNFR1 and TNFR2. ATD5 could also reduce the TNF-α-mediated cytotoxicity and inhibit TNF-α-meditated caspase activation on L929 cells in a dose dependent manner. The activity of ATD5 was significantly stronger than three peptides displayed by ATD5. This study provides a novel strategy for the development of new TNF-α inhibitors. This study demonstrates that it is possible to screen potential antagonists of TNF-α using in vitro analysis systems in combination with the computer-aided modeling method. [Copyright &y& Elsevier]

Abstract: Human interleukin-6 is involved in the maintenance and progression of several diseases such as multiple myeloma (MM), rheumatoid arthritis, or osteoporosis. Our previous work demonstrated that an interleukin-6 antagonist peptide (named PT) possessed potential bioactivity to antagonize the function of hIL-6 and could efficiently induce the growth arrest and apoptosis of XG-7 and M1 cells in a dose-dependent manner. In this study, the theoretical interaction of the peptide PT with its receptor was analyzed further more with molecular docking and molecular dynamics methods. The theoretical studies showed that PT possessed very high affinity to interleukin-6R and offered a practical means of imposing long-term blockade of interleukin-6 activity in vivo. According to the theoretical results, the biological evaluation of PT was researched on two different cells models with more sensitive approaches: (1) The antagonist activity of PT was studied on the interleukin-6 dependent MM cells (XG-7) cultured with interleukin-6. In the other interleukin-6 dependent MM cells (SKO-007), they survived themselves by auto/paracrine without the exogenous interleukin-6, and also could be antagonized by PT. The therapeutic value of PT only limited on the interleukin-6 dependent category in MM. (2) Myeloid leukemia M1 cells were induced for growth arrest and apoptosis in response to interleukin-6. The results supported our previous findings and showed that PT could be evaluated by protecting the cells from interleukin-6 induced apoptosis. In conclusion, PT could induce interleukin-6-dependent XG-7 and SKO-007 cells to apoptosis while inhibit interleukin-6-stimulated apoptosis in M1 cells. [Copyright &y& Elsevier]

Abstract: Tumor necrosis factor-α (TNF-α) antagonists have become therapeutic drugs for immunological diseases including rheumatoid arthritis, inflammatory bowel disease, Crohn''s disease, etc. Low molecular weight synthetic peptides can mimic the binding sites of TNF-α receptors and block the activity of TNF-α. Based on the 3-D complex structure of TNF-α with its neutralizing monoclonal antibody (Mab) Z12, an antagonistic peptide (AP) was rationally de novo designed. The designed AP possessed similar structural character and potential bioactivity with Mab Z12. AP could competitively inhibit the binding of Mab Z12 to TNF-α, TNF-α-meditated caspase activation and TNF-α-induced cytotoxicity on murine L929 cells with a dose-dependent fashion. This study highlights the potential of computation-aided method for the design of novel peptides with the ability to block the deleterious biological effects of TNF-α. [Copyright &y& Elsevier]

Abstract: B lymphocyte stimulator (BLyS) is a member of tumor necrosis factor (TNF) family. Because of its roles in autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and Sjogren syndrome (SS), BLyS antagonists have been tested to treat SLE- and RA-like symptoms in mice and obtained optimistic results. So far, reported BLyS antagonists were mostly decoyed BLyS receptors or anti-BLyS antibodies. In this study, a novel BLyS antagonist peptide, PT, was designed based on the modeling 3-D complex structure of BCMA and BLyS. The interaction mode of PT with BLyS was analyzed theoretically. The results of competitive ELISA demonstrated that PT could inhibit the binding of BCMA-Fc and anti-BLyS antibody to BLyS in vitro. In addition, PT could partly block the proliferating activity of BLyS on mice splenocytes. The BLyS antagonizing activity of PT was significant (p <0.05). This study highlights the possibility of using BLyS antagonist peptide to neutralize BLyS activity. Further optimization of PT with computer-guided molecular design method to enhance its biopotency may be useful in developing new BLyS antagonists to treat BLyS-related autoimmune diseases. [Copyright &y& Elsevier]

Abstract: The variable regions of antibodies play central roles in the binding with antigens. Based on the model of a tumour necrosis factor-α (TNF-α) neutralizing monoclonal antibody (named as Z12) with TNF-α, heavy chain CDR2 (HCDR2) and light chain CDR3 (LCDR3) of Z12 were found to be the most responsible to bind with TNF-α. A mimetic peptide (PT) was designed based on the sequence derived from HCDR2 and LCDR3. Fusion protein PT-Fc was constructed by linking PT with Fc of human IgG1 through a flexible linker (GGGGGS). The primary structural characteristics of Fc and PT-Fc were analyzed, including the flexibility, hydrophilicity and epitopes. It was demonstrated that PT and Fc in the fusion protein possessed bio-function properly and non-interfering with each other. Furthermore, PT-Fc was expressed in Escherichia coli by fusion with thioredoxin (Trx). After trx-PT-Fc was cleaved with recombinant enterokinase, PT-Fc was obtained. The results of in vitro cytotoxic assays showed that both PT and PT-Fc could efficiently inhibit TNF-α induced apoptosis on L929 cells. At the same micromole concentration, the inhibition activity of PT-Fc was significantly higher than PT. [Copyright &y& Elsevier]

Abstract: The murine monoclonal antibody Z12 is of therapeutic interest for its neutralizing biological activity against human tumor necrosis factor-α (hTNF-α). We attempted to humanize Z12 with variable domain resurfacing guided by computer modeling. First, the genes of heavy and light chain variable region (VH, VL) of Z12 were cloned and the whole three-dimensional structure of Fv fragment was constructed by using homology-based modeling and molecular docking methods. Then the complex model of Fv interacting with hTNF-α whose crystal structure derived from PDB database was gained with computer-guided docking program. Based on this model, a humanized version was designed. The humanized Fab antibody was constructed, expressed and purified in the pComb3H vector system and it showed unaltered binding affinity to the antigen as determined by ELISA and atomic force microscopy (AFM). The method described here can be used to humanize other anti-hTNF-α antibodies. [Copyright &y& Elsevier]

Abstract: The development of rational methods to design antagonist peptides based on the 3-D structure of protein active region has, to now, been only marginally successful. This has been largely due to the difficulty of constraining the recognition elements of a mimetic structure to the relative conformational and spatial orientations present in the parent molecule. According to the 3-D complex structure of human interleukin-6 (hIL-6) and its receptor (hIL-6R), a novel antagonist peptide (named PT), which possessed potential bioactivity of hIL-6, was designed by the means of distance geometry, molecular modeling and molecular dynamics trajectory analysis. The bioactivity of the designed peptide (i.e. PT) was evaluated using XG-7 cells, a hIL-6-dependent B-cell line. PT possessed potential bioactivity to antagonize the function of hIL-6 and could efficiently induce the growth arrest and apoptosis of XG-7 cells in a dose-dependent manner. [Copyright &y& Elsevier]

Abstract: The variable regions of antibody molecules bind antigens with high affinity and specificity. The binding sites are imparted largely to the hypervariable portions (i.e. CDRs) of the variable region. Peptides derived from antibody CDRs can bind antigen with similar specificity acted as mimic of antibody and become drug-designing core, although with markedly lower affinity. In this study, the 3D complex structure of tumor necrosis factor-alpha (TNFα) and its neutralizing monoclonal antibody Z12 was modeled using molecular docking method and optimized with molecular mechanism and dynamics method. The binding domains between TNFα and Z12 were determined theoretically and functional antigen epitopes were predicted. According to the 3D complex structure of TNFα and Z12, a novel antagonist peptide, named PT1, was designed theoretically. The experimental result showed that PT1 possessed significantly binding inhibition of TNFα to Z12 and protected L929 cells from the cytotoxic effect of TNFα. The designed mimic peptide was more amenable to synthetic chemistry and thus might be useful starting points for the design of smaller organic mimics. [Copyright &y& Elsevier]

Based on the complex crystal structure of human interleukin-6 (hIL-6) and its receptor (hIL-6R), a novel hIL-6 antagonist peptide (named PT) was designed using computer-guided design method. Dealing with molecular docking and molecular dynamics methods, the interaction between PT and hIL-6R was analyzed. The theoretical studies showed that PT possessed very high affinity to hIL-6R and offered a practical means of imposing long-term blockade of hIL-6 activity in vivo. This effect was examined due to growth arrest and apoptosis induced by hIL-6 in myeloblastic cell line M1 cells in a dose-dependent manner. The findings demonstrate that PT could also act as an excellent antagonist candidate for the induction of growth arrest and apoptosis. Furthermore, murine M1 myeloid cell line, which was induced by the physiological inducer hIL-6 to undergo apoptosis and growth arrest, could be used as a subtle model system to test hIL-6 antagonist. [Copyright &y& Elsevier]

The variable regions of antibody molecules bind antigens with high affinity and specificity. The binding sites are imparted largely to the hypervariable portions (i.e., CDRs) of the variable region. Peptides derived from CDRs can bind antigen with similar specificity acting as mimic of antibody and become drug-designing core, although with markedly lower affinity. In order to increase the affinity and bioactivity, in this study, a novel peptide (PT) designed on CDRs of a TNFα neutralizing monoclonal antibody Z12 was linked with Fc fragment of human IgG1. The interaction mode of PT-linker-Fc (PLF) with TNFα was analyzed with computer-guided molecular modeling method. After expression in Escherichia coli and purification, recombinant PT-linker-Fc could bind directly with the TNFα coated on the ELISA plates. Furthermore, PLF could competitively inhibit the binding of Z12 to TNFα and also inhibit the TNFα-induced cytotoxicity on L929 cells. The TNFα antagonizing activity of PLF was significantly higher than that of the free peptide. This study highlights the potential of human Fc to enhance the potency of peptides designed on the CDRs of antibodies and could be useful in developing new TNFα antagonists. [Copyright &y& Elsevier]

The interaction between human interleukin-6 (hIL-6) and human interleukin-6 receptor (hIL-6R) is the initial and most specific step in the hIL-6 signaling pathway. Understanding its binding core and interaction mechanism at amino acid level is the basis for designing small IL-6 inhibiting molecules, such as peptides or lead compounds. With Docking method, the complex structure composed of hIL-6 and its α-subunit receptor (hIL-6R) was analyzed theoretically. By using structure-based analysis and phage display methods, the loop AB (from Lys67 to Glu81) of hIL-6 was found to be the important binding epitope of hIL-6R. By means of computer-aided design, the mimic antagonist peptide (14 residues) was designed and synthesized. Using multiple myeloma cell line (XG7), IL-6 dependent cell line, as test model, the influence of antagonist peptides on the proliferation of XG7 cells was investigated. The results showed that the synthetic peptide could be competitive to bind to hIL-6R with hIL-6, and the effect was concentration dependent. The theoretical design approach is a powerful alternative to phage peptide library for protein mimics. Such mini-peptide is more amenable to synthetic chemistry and thus may be useful starting points for the design of small organic mimics. [Copyright &y& Elsevier]

The 3-D complex structures of extracellular domain of human CD16 (FcγRIII) and hIgG1 or B88-9 were obtained by means of computer-guided molecular modeling, respectively. The binding epitopes were predicted and binding energy was calculated theoretically. The epitopes of human CD16 interacted with hIgG1 and B88-9 were different and the binding energy of B88-9 was stronger than hIgG1. The computer competing simulation results showed that B88-9 could bind to CD16 when CD16 was also bound by hIgG1, while IgG1 could not bind to CD16 after CD16 was bound by B88-9. By flow cytometry analysis, the competitive binding activity of B88-9 to CD16 with hIgG1 was evaluated. With the increasing concentrations of hIgG1, the binding activity of B88-9 was not interfered markedly. It suggested that hIgG1 could not inhibit the interaction of CD16 and B88-9 and the binding domain of hIgG1 and B88-9 on CD16 was different. [Copyright &y& Elsevier]

Several studies have focused on the effect of different lengths of linker peptides on the properties of single-chain Fv (ScFv). The expressing level and stability of anti-CD16 ScFv with common linker peptide (Gly4Ser)3 were very poor. Considering 3-D structures of heavy and light chain variable region gene of anti-CD16 antibody, a novel linker peptide PT7 (i.e. Gly3SerAla3) was designed. As a comparison, the linker PT5 (Gly4Ser) was chosen to construct anti-CD16 ScFv. A molecular modeling of anti-CD16 ScFv antibody with the two different linker peptides was designed using computer-assisted modeling techniques and molecular dynamics method. Based on the crystal structure of human IgG1 Fc fragment–Fc γ receptor III (Fc γ RIII) complex, putative interactions between anti-CD16 ScFv antibody with two different linker peptide and Fc γ receptor III fragment were predicted with Docking method. Using molecular graphic techniques, the structure–function relationship of anti-CD16 ScFv antibody with two different linker peptides was analyzed and the combining ability was predicted. The binding activity to Daudi cells by FACS showed that anti-CD16 ScFv antibody with two different linker peptides possessed similar ability and the experimental result was consistent with the theoretical prediction. [Copyright &y& Elsevier]

Influenza A viruses (IAVs) continue to pose a huge threat to public health, and their prevention and treatment remain major international issues. Neuraminidase (NA) is the second most abundant surface glycoprotein on influenza viruses, and antibodies to NA have been shown to be effective against influenza infection. In this study, we generated a monoclonal antibody (mAb), named FNA1, directed toward N1 NAs. FNA1 reacted with H1N1 and H5N1 NA, but failed to react with the NA proteins of H3N2 and H7N9. In vitro, FNA1 displayed potent antiviral activity that mediated both NA inhibition (NI) and blocking of pseudovirus release. Moreover, residues 219, 254, 358, and 388 in the NA protein were critical for FNA1 binding to H1N1 NA. However, further validation is necessary to confirm whether FNA1 mAb is indeed a good inhibitor against NA for application against H1N1 and H5N1 viruses. [ABSTRACT FROM AUTHOR]

Highlights from the article: Innentitelbild: Dimension-Matched Zinc Phthalocyanine/BiVO4 Ultrathin Nanocomposites for CO2 Reduction as Efficient Wide-Visible-Light-Driven Photocatalysts via a Cascade Charge Transfer (Angew. Keywords: BiVO4-Nanoschichten; CO2-Umwandlung; Katalyse mit sichtbarem Licht; Nanokomposite; Phthalocyanine BiVO4-Nanoschichten, CO2-Umwandlung, Katalyse mit sichtbarem Licht, Nanokomposite, Phthalocyanine.

A universal strategy is developed to construct a cascade Z‐Scheme system, in which an effective energy platform is the core to direct charge transfer and separation, blocking the unexpected type‐II charge transfer pathway. The dimension‐matched (001)TiO2‐g‐C3N4/BiVO4 nanosheet heterojunction (T‐CN/BVNS) is the first such model. The optimized cascade Z‐Scheme exhibits ≈19‐fold photoactivity improvement for CO2 reduction to CO in the absence of cocatalysts and costly sacrificial agents under visible‐light irradiation, compared with BVNS, which is also superior to other reported Z‐Scheme systems even with noble metals as mediators. The experimental results and DFT calculations based on van der Waals structural models on the ultrafast timescale reveal that the introduced T as the platform prolongs the lifetimes of spatially separated electrons and holes and does not compromise their reduction and oxidation potentials. [ABSTRACT FROM AUTHOR]

A universal strategy is developed to construct a cascade Z‐Scheme system, in which an effective energy platform is the core to direct charge transfer and separation, blocking the unexpected type‐II charge transfer pathway. The dimension‐matched (001)TiO2‐g‐C3N4/BiVO4 nanosheet heterojunction (T‐CN/BVNS) is the first such model. The optimized cascade Z‐Scheme exhibits ≈19‐fold photoactivity improvement for CO2 reduction to CO in the absence of cocatalysts and costly sacrificial agents under visible‐light irradiation, compared with BVNS, which is also superior to other reported Z‐Scheme systems even with noble metals as mediators. The experimental results and DFT calculations based on van der Waals structural models on the ultrafast timescale reveal that the introduced T as the platform prolongs the lifetimes of spatially separated electrons and holes and does not compromise their reduction and oxidation potentials. [ABSTRACT FROM AUTHOR]

Purpose: Mitogen-activated protein kinases (MAPK), specifically the c-Jun N-terminal kinase (JNK)–MAPK subfamily, play a crucial role in the development of various cancers, including hepatocellular carcinoma (HCC). However, the specific roles of JNK1/2 and their upstream regulators, MKK4/7, in HCC carcinogenesis remain unclear. Methods: In this study, we performed differential expression analysis of JNK–MAPK components at both the transcriptome and protein levels using TCGA and HPA databases. We utilized Kaplan–Meier survival plots and receiver operating characteristic (ROC) curve analysis to evaluate the prognostic performance of a risk scoring model based on these components in the TCGA-HCC cohort. Additionally, we conducted immunoblotting, apoptosis analysis with FACS and soft agar assays to investigate the response of JNK–MAPK pathway components to various death stimuli (TRAIL, TNF-α, anisomycin, and etoposide) in HCC cell lines. Results: JNK1/2 and MKK7 levels were significantly upregulated in HCC samples compared to paracarcinoma tissues, whereas MKK4 was downregulated. ROC analyses suggested that JNK2 and MKK7 may serve as suitable diagnostic genes for HCC, and high JNK2 expression correlated with significantly poorer overall survival. Knockdown of JNK1 enhanced TRAIL-induced apoptosis in hepatoma cells, while JNK2 knockdown reduced TNF-α/cycloheximide (CHX)—and anisomycin-induced apoptosis. Neither JNK1 nor JNK2 knockdown affected etoposide-induced apoptosis. Furthermore, MKK7 knockdown augmented TNF-α/CHX- and TRAIL-induced apoptosis and inhibited colony formation in hepatoma cells. Conclusion: Targeting MKK7, rather than JNK1/2 or MKK4, may be a promising therapeutic strategy to inhibit the JNK–MAPK pathway in HCC therapy. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus causes a wide range of infectious diseases. Treatment of these infections has become increasingly difficult due to the widespread emergence of antibiotic-resistant strains; therefore, it is essential to explore effective alternatives to antibiotics. A secreted protein of S. aureus, known as eLtaS, is an extracellular protein released from the bacterial membrane protein, LtaS. However, the role of eLtaS in S. aureus pathogenesis remains largely unknown. Here we show eLtaS dramatically aggravates S. aureus infection by binding to C3b and then inhibiting the phagocytosis of C3b-deposited S. aureus. Furthermore, we developed a monoclonal antibody against eLtaS, MAE4, which neutralizes the activity of eLtaS and blocks staphylococcal evasion of phagocytosis. Consequently, MAE4 is capable of protecting mice from lethal S. aureus infection. Our findings reveal that targeting of eLtaS by MAE4 is a potential therapeutic strategy for the treatment of infectious diseases caused by S. aureus. [ABSTRACT FROM AUTHOR]

The continuous mutation of SARS-CoV-2 has presented enormous challenges to global pandemic prevention and control. Recent studies have shown evidence that the genome sequence of SARS-CoV-2 nucleocapsid proteins is relatively conserved, and their biological functions are being confirmed. There is increasing evidence that the N protein will not only provide a specific diagnostic marker but also become an effective treatment target. In this study, 2G4, which specifically recognizes the N protein, was identified by screening a human phage display library. Based on the computer-guided homology modelling and molecular docking method used, the 3-D structures for the 2G4 scFv fragment (VH-linker-VL structure, with (G4S)3 as the linker peptide in the model), SARS-CoV-2 N protein and its complex were modelled and optimized with a suitable force field. The binding mode and key residues of the 2G4 and N protein interaction were predicted, and three mutant antibodies (named 2G4-M1, 2G4-M2 and 2G4-M3) with higher affinity were designed theoretically. Using directed point mutant technology, the three mutant antibodies were prepared, and their affinity was tested. Their affinity constants of approximately 0.19 nM (2G4-M1), 0.019 nM (2G4-M2) and 0.075 nM (2G4-M3) were at least one order of magnitude lower than that of the parent antibody (3 nM; 2G4, parent antibody), as determined using a biolayer interferometry (BLI) assay. It is expected that high-affinity candidates will be used for diagnosis and even as potential therapeutic drugs for the SARS-CoV-2 pandemic. [ABSTRACT FROM AUTHOR]

BLyS antagonists have become the therapeutic reagents in the treatment of autoimmune disorders. BLyS binding peptides and their Fc fusion proteins may be alternative BLyS antagonists in such application. In this study, the activity of BLyS binding peptide 814 obtained from phage display library and peptide TA designed by computer-aided modeling on the interaction of BLyS–TACI was compared. In addition, to maintain the spatial conformation and stability of the peptides, human IgG1 Fc fragment was fused to peptides 814 and TA to form peptide-Fc fusion proteins, steady and innovative peptibodies. The prokaryotic expression plasmids pET30a-814-Fc and pET30a-TA-Fc for these peptibodies were acquired by genetic engineering, and confirmed by DNA sequencing. After the right plasmids were transformed into Escherichia coli BL21 (DE3), the fusion proteins were expressed and purified by protein A affinity column. As a result of competitive ELISA, peptides 814 and TA at 100 μg/ml displayed 52.2% and 28.6% inhibition on the interaction of TACI-Fc with BLyS respectively. Moreover, 814-Fc and TA-Fc fusion proteins could bind to BLyS in a dosage-dependent manner as TACI-Fc did, and displayed 54.7% and 26.1% inhibition on the interaction of TACI-Fc-Myc with BLyS at 100 μg/ml respectively. So 814-Fc and TA-Fc proteins had the similar bioactivity as the peptides did. Furthermore, compared with TA-Fc, 814-Fc showed two-fold inhibition effect on BLyS binding to TACI, suggesting that 814-Fc could inhibit BLyS bioactivity significantly and might serve as a potential antagonist to treat autoimmune diseases associated with BLyS overexpression. [ABSTRACT FROM AUTHOR]

Marburg virus (MARV), one member of the Filoviridae family, cause sporadic outbreaks of hemorrhagic fever with high mortality rates. No countermeasures are currently available for the prevention or treatment of MARV infection. Monoclonal antibodies (mAbs) are promising candidates to display high neutralizing activity against MARV infection in vitro and in vivo. Recently, growing evidence has shown that immune effector function including antibody-dependent cell-mediated cytotoxicity (ADCC) is also required for in vivo efficacy of a panel of antibodies. Glyco-engineered methods are widely utilized to augment ADCC function of mAbs. In this study, we generated a fucose-knockout MARV GP-specific mAb named AF-04 and showed that afucosylation dramatically increased its binding affinity to polymorphic FcγRIIIa (F176/V176) compared with the parental AF-03. Accordingly, AF-04-mediated NK cell activation and NFAT expression downstream of FcγRIIIa in effector cells were also augmented. In conclusion, this work demonstrates that AF-04 represents a novel avenue for the treatment of MARV-caused disease. • Inhibition of MARV pseudovirus entry in vitro and in vivo. • Afucosylation dramatically increased its binding affinity to polymorphic FcγRIIIa (F176/V176). • AF-04-mediated NK cell activation and NFAT expression downstream of FcγRIIIa in effector cells was also augmented. [ABSTRACT FROM AUTHOR]

Lactic acid was originally a by‐product of glucose metabolism, but many studies have shown that lactic acid plays a vital role in regulating immune cell polarization, differentiation and effector functions. In this study, we provide evidence that lactic acid and low pH impaired the effector function of CD4+ T cells in response to TCR and non‐TCR stimulation. Specifically, lactic acid or hydrochloric acid treatment significantly decreased IL‐2 and IFN‐γ production as well as CD25/CD69 expression. Furthermore, although MCT1 was required for the suppression of CD25 and CD69 expression by lactic acid, using pharmacological inhibition and genetic deletion, we demonstrated that it was dispensable for lactic acid‐mediated inhibition of IL‐2 and IFN‐γ production. [ABSTRACT FROM AUTHOR]

Abstract: Inhibition of C5a by antibodies has been demonstrated to dramatically improve survival in various sepsis models in mice and rats. The structural basis of C5a mediated bioactivity and C5a antibody mediated neutralization are of interesting to be investigated. In the previous study, we obtained a novel functional mouse antibody named as F20. With computer-guided modeling method, the 3-D theoretical structure of F20 Fv fragment was constructed. Using the crystal structure of C5a, the 3-D complex structure of C5a and F20 Fv fragment was modeled with molecular docking method. Based on distance geometry method and intermolecular interaction theory, the key residue Lys68 in C5a identified by F20 was predicted. The mutant experimental results showed that the residue Lys68 was the critical residue of C5a for it''s bioactivity and F20 binding activity. The present study shed new light on the structural basis of C5a mediated bioactivity. The identification of the critical residue will provide useful information for human complement C5a targeted therapeutic intervention. [Copyright &y& Elsevier]

Abstract: Since B cell activating factor belonging to tumor necrosis factor (TNF) family (BAFF) has been identified as a critical factor for B cell maturation and survival, convincing evidence indicates that deregulation of BAFF is involved in pathogenesis of B cell related autoimmune diseases. Blockade of BAFF activity significantly improves the symptoms of autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis both in animal models and clinical trials. Therefore, BAFF-targeting therapy is a promising approach to treat B cell related autoimmune diseases. [Copyright &y& Elsevier]

Abstract: The neutralizing activity of three anti-human TNF monoclonal antibodies, designated D2, E6, and F6 were investigated by three experimental systems. The results from the systems showed that all the three mAbs could neutralize TNF-mediated cytotoxicity in L929 cells, TNF-induced NF-κB activation in ECV304 cells, and TNF-upregulated ICAM-1 surface expression on ECV304 cells in dose-dependent manners. D2 had the highest neutralizing activity of the three mAbs, and F6 had higher level of neutralizing activity than E6. We also cloned the VH and VL cDNAs and obtained their cDNA sequences. The sequences were used in molecular modeling to establish the complex structures of TNF with variable regions of the three mAbs, respectively. In the structures, the TNF epitopes of D2, E6, and F6 were predicted at amino acids of (A109, A111–A112, C19, C21–C29, C44–C46, C66–C75, C77, C79, C90, C101, C103, C105, C114, C134–C148), (C18–C19, C21–C30, C32, C37, C43–C47, C67–C75, C83, C105–C106, C131, C135–C141), and (C21–C32, C45–C47, C65, C67–C72, C74, C81, C83, C90–C95, C105–C113, C133–C147), respectively, and the affinities of D2, E6, and F6 to TNF were predicted as −252.69, −232.83, and −299.92kcal, respectively. Moreover, we proved the binding ability of F6 to the epitopes of amino acids of 141–146 in TNF molecule was better than that of E6, and that of D2 was the best of the three mAbs by Western blot and ELISA, in which the mutant TNF deleted the amino acids of 141–146 in TNF molecule was employed. These results make a basic foundation for selecting candidate mAbs for various purposes, such as construction of chimeric or humanized mAbs for therapeutic purpose, establishment of ELISA kits for determination of TNF, and production of affinity columns to purify TNF. [Copyright &y& Elsevier]

Bispecific antibody (BsAb) can physically cross-link immune cells to tumor cells, circumventing the proper structures for tumor cell–immune cell interactions and activating the cellular cytotoxic mechanisms. The optimal BsAb should target tumor cells with high affinity, but activate trigger molecules on cytotoxic cells by monovalent binding of Fab fragments. In the present study, a trivalent anti-erbB2/anti-CD16 BsAb was produced. This BsAb possesses bivalent arms specifically binding to the extracellular domain of erbB2 and monovalent Fab fragment redirecting NK cells. The recombinant protein could be expressed and purified from Escherichia coli as native proteins without refolding. It was fully functional in bispecific binding to SKBR3 and NK cells. The molecular size of this trivalent BsAb protein is larger than diabody and smaller than whole antibody and expected to have advantages for both high penetration of small antibody fragments and the slow circulation clearance of whole antibody. This novel protein may be an attractive target for further improvement and evaluation. [Copyright &y& Elsevier]

Presents a study which examined the three-dimensional (3-D) structure of the extracellular ligand-binding domain of human interleukin-6 receptor (hIL-6R) constructed by means of computer-guided homology modeling techniques. Theoretical method used; Results; Discussion.

Staphylococcal enterotoxin B (SEB), one of the exotoxins produced by Staphylococcus aureus , is the key toxin that causes poisoning reactions and toxic shock syndrome. In the current research work, a novel human antibody named LXY8 was screened from a human phage display antibody library, and LXY8 blocked the interaction between SEB and the T cell receptor (TCR). The binding activity between LXY8 and SEB was 0.525 nM. Furthermore, LXY8 could effectively inhibit the SEB-induced activation of peripheral blood mononuclear cells and release of cytokines. In the BALB/c mouse model, LXY8 effectively neutralized SEB toxicity in vivo. Finally, based on computer-guided molecular modeling, we designed a series of SEB mutation sites; these sites facilitated the determination of the key residues (i.e. 176EFNN179) of SEB recognized by LXY8. The research revealed that the 176EFNN179 residues of SEB are important for specific antibody-antigen recognition. The results may be helpful for the development of antibody-based therapy for SEB-induced toxic shock syndrome. • A novel human antibody (LXY8) blocked the interaction between SEB and the T cell receptor. • LXY8 can effectively neutralize SEB toxicity in vitro and vivo. • the 176EFNN179 residues of SEB are important for antibody recognition. [ABSTRACT FROM AUTHOR]

Extensive amounts of multi-omics data and multiple cancer subtyping methods have been developed rapidly, and generate discrepant clustering results, which poses challenges for cancer molecular subtype research. Thus, the development of methods for the identification of cancer consensus molecular subtypes is essential. The lack of intuitive and easy-to-use analytical tools has posed a barrier. Here, we report on the development of the COnsensus Molecular SUbtype of Cancer (COMSUC) web server. With COMSUC, users can explore consensus molecular subtypes of more than 30 cancers based on eight clustering methods, five types of omics data from public reference datasets or users' private data, and three consensus clustering methods. The web server provides interactive and modifiable visualization, and publishable output of analysis results. Researchers can also exchange consensus subtype results with collaborators via project IDs. COMSUC is now publicly and freely available with no login requirement at http://comsuc.bioinforai.tech/ (IP address: http://59.110.25.27/). For a video summary of this web server, see S1 Video and S1 File. Author summary: A number of methods have been developed for omics data-based subtyping, which has been widely accepted as a relevant source of cancer classification. However, discrepant results hamper the translational and clinical utility of these methods. In this study, we have developed the COnsensus Molecular SUbtype of Cancer (COMSUC) web server to provide a user-friendly tool for integrating discrepant clustering results based on multiple platform, multiple omics data and multiple methods. COMSUC provides powerful support to users to decipher the cancer Consensus Molecular Subtypes (CMSs), a consensus classification system integrating different clustering results. [ABSTRACT FROM AUTHOR]

As phenolic compounds, alkyl gallates may inhibit the activity of digestive enzymes for starch. Furthermore, their alkyl chains may facilitate starch inclusion complexation and results in an increased resistant starch (RS) content or slowly digestible starch (SDS) content, which may further retard starch digestion. The significance of such inhibition is that the rate of starch hydrolysis into glucose is reduced, thereby preventing hyperglycemia and related metabolic diseases. This study examined the inhibitory effects on in vitro enzymatic digestion of starch by gallic acid and five alkyl gallates of varying alkyl chain lengths, i.e., butyl gallate, octyl gallate, dodecyl gallate, hexadecyl gallate, and octadecyl gallate. Raw and cooked potato starch (PS) and high-amylose maize starch (HAMS) were tested. For both types of raw starch, gallic acid and all the alkyl gallates significantly (p < 0.05) increased RS content except for octadecyl gallate. In the case of cooked starch, the RS contents were markedly decreased (p < 0.05) as compared to those in raw starch, because gelatinization caused an overall greater susceptibility to enzymatic digestion. The reduction in RS content was less in cooked HAMS than that in cooked PS, due to a higher gelatinization temperature range of HAMS. The aforementioned effect of gallates on RS content was also found for cooked PS, while cooked HAMS experienced increased RS only with gallic acid and butyl gallate. Overall, for the digestion of both starches, regardless of raw or cooked, gallic acid and alkyl gallates with shorter chains demonstrated the strongest inhibitory effects. Our findings indicate that shorter alkyl gallates are effective in inhibiting enzymatic digestion of starch and therefore may have potential in modulating glycemic response. Image 1 • Gallates reduced digestibility of potato (PS) and high amylose maize starch (HAMS). • Resistant starch increased in the presence of gallic acid and alkyl gallates. • Inhibition on starch digestion decreased with increasing alkyl chain length. • Digestibility of PS more affected than HAMS by cooking. • Gallates may form inclusion complex with cooked HAMS that resisted digestion. [ABSTRACT FROM AUTHOR]

AXL receptor tyrosine kinase ligand (AXL), a tyrosine kinase receptor that is commonly overexpressed in numerous types of cancer, significantly promotes drug resistance and metastasis in tumor cells. Inhibition of the AXL/growth arrest-specific 6 (Gas6) signaling pathway is emerging as a potential anticancer therapeutic strategy. In the present study, on the basis of the three-dimensional complex structure of AXL/Gas6, the critical residues (E56, E59 and T77) in AXL binding to Gas6 were determined using computer graphics analysis and the distance geometry method. Subsequently, four-variant AXL−ECD-Fc-M1 (G32S, D87G, V92A and G127R) and AXL−ECD-Fc-M2 (G32A, D87A, V92A and G127A) were predicted as high-affinity mutants; AXL−ECD-Fc-M3 (E56R and T77R) and AXL−ECD-Fc-M4 (E59R and T77R) were predicted as low-affinity mutants. The results of the present study revealed that the half-maximal effect concentrations of AXL−ECD-Fc-M1 and AXL−ECD-Fc-M2 were ~0.141 and 0.375 µg/ml, respectively, whereas that of the wild-type protein (AXL−ECD-Fc-WT) was 0.514 µg/ml. Furthermore, adding the high-affinity mutants into culture medium to capture free Gas6 significantly inhibited AXL/Gas6 binding and thus blocked the downstream signaling pathway. In addition, the high-affinity mutants effectively suppressed the migration and metastasis of SKOV3 and A549 cells. Conversely, compared with AXL−ECD-Fc-WT, the low-affinity AXL mutants AXL−ECD-Fc-M3 and AXL−ECD-Fc-M4 lost all inhibitory activities. These findings highlight AXL as a potential therapeutic target and demonstrated that the key residues E56, E59 and T77 may be crucial sites for abolishing the activity of the AXL/Gas6 pathway in cancer therapy. [ABSTRACT FROM AUTHOR]

CD47, as an innate immune checkpoint molecule, is an important target of cancer immunotherapy. We previously reported that a high-affinity SIRPα variant FD164 fused with IgG1 subtype Fc showed a better antitumor effect than wild-type SIRPα in an immunodeficient tumor-bearing model. However, CD47 is widely expressed in blood cells, and the drugs targeting CD47 may cause potential hematological toxicity. Herein, we modified the FD164 molecule by Fc mutation (N297A) to inactivate the Fc-related effector function and named it nFD164. Moreover, we further studied the potential of nFD164 as a candidate drug targeting CD47, including the stability, in vitro activity, antitumor activity of single or combined drugs in vivo , and hematological toxicity in humanized CD47/SIRPα transgenic mouse model. The results show that nFD164 maintains strong binding activity to CD47 on tumor cells, but has weak binding activity with red blood cells or white blood cells, and nFD164 has good drug stability under accelerated conditions (high temperature, bright light and freeze-thaw cycles). More importantly, in the immunodeficient or humanized CD47/SIRPα transgenic mice bearing tumor model, the combination of nFD164 and anti-CD20 antibody or anti-mPD-1 antibody had a synergistic antitumor effect. Especially in transgenic mouse models, nFD164 combined with anti-mPD-1 significantly enhanced tumor suppressive activity compared with anti-mPD-1 (P < 0.01) or nFD164 (P < 0.01) as a single drug and had fewer hematology-related side effects than FD164 or Hu5F9-G4. When these factors are taken together, nFD164 is a promising high-affinity CD47-targeting drug candidate with better stability, potential antitumor activity, and improved safety profile. [Display omitted] • nFD164 exhibits high tumor targeting effect and weak blood cell binding activity. • nFD164 exhibits potent synergistic anti-tumor effect with anti-CD20 or anti-PD-1 antibody. • nFD164 maintains favorable hematological safety in transgenic mice model. • nFD164 shows good structural stability, pharmacological properties, and potential for drug development. • nFD164 could be a promising therapeutic drug candidate for solid tumor or hematological malignancies. [ABSTRACT FROM AUTHOR]

A combination of computation techniques and peptide mutants have been used to determine the binding site and amino acid residues on the inhibitor peptide that are critical for binding to Mitogen-activated protein kinase 14 (p38α). In our previous research work, the functional peptide, named as PT5, target to p38α, was obtained based on the theoretical complex structure of p38α and [transforming growth factor-β (TGF-β)-activated protein kinase 1 (TAK1)-binding protein 1] (TAB1). Based on the computer-guided ab initio modeling method, the inhibitor peptide PT5 and its mutants were modeled. Furthermore, the 3-D complex structures of PT5 or its mutants and p38α were constructed using molecular docking and dynamics simulation methods. The key residues in the peptide PT5 involved in binding interaction to p38α were predicted. According to the 3-D theoretical complex structure PT5/ p38α, the interaction binding mode between PT5 and p38α was analyzed using distance geometry technology. Mutants of the peptide PT5 was used to evaluate the bio-function when the critical residues were mutated. The mutant experimental results identified the key residues in PT5, i.e. Thr11 and Asp12 and determined the core sequence of PT5 binding to p38α. Based on the results, optimized peptides compounds could be developed for treating myocardial ischemia/reperfusion (I/R) injury in clinical. [ABSTRACT FROM AUTHOR]

The Nod-like receptor protein 3 ( NLRP3) inflammasome plays roles in host defence against invading pathogens and in the development of autoimmune damage. Strict regulation of these responses is important to avoid detrimental effects. Here, we demonstrate that T cell Ig mucin-3 (Tim-3), an immune checkpoint inhibitor, inhibits NLRP3 inflammasome activation by damping basal and lipopolysaccharide-induced nuclear factor- κB-mediated up-regulation of NLRP3 and interleukin-1 β during the priming step and basal and ATP/lipopolysaccharide-induced ATP production, K+ efflux, and reactive oxygen species production during the activation step. Residues Y256/Y263 in the C-terminal region of Tim-3 are required for these inhibitory effects on the NLRP3 inflammasome. In mice with alum-induced peritonitis, blockade of Tim-3 exacerbates peritonitis by overcoming the inhibitory effect of Tim-3 on NLRP3 inflammasome activation, while transgenic expression of Tim-3 attenuates inflammation by inhibiting NLRP3 inflammasome activation. Our results show that Tim-3 is a critical negative regulator of NLRP3 inflammasome and provides a potential target for intervention of diseases with uncontrolled inflammasome activation. [ABSTRACT FROM AUTHOR]

Middle East respiratory syndrome coronavirus (MERS-CoV) is continuously spreading and causing severe and fatal acute respiratory disease in humans. Prophylactic and therapeutic strategies are therefore urgently needed to control MERS-CoV infection. Here, we generated a humanized monoclonal antibody (mAb), designated hMS-1, which targeted the MERS-CoV receptor-binding domain (RBD) with high affinity. hMS-1 significantly blocked MERS-CoV RBD binding to its viral receptor, human dipeptidyl peptidase 4 (hDPP4), potently neutralized infection by a prototype MERS-CoV, and effectively cross-neutralized evolved MERS-CoV isolates through recognizing highly conserved RBD epitopes. Notably, single-dose treatment with hMS-1 completely protected hDPP4 transgenic (hDPP4-Tg) mice from lethal infection with MERS-CoV. Taken together, our data suggest that hMS-1 might be developed as an effective immunotherapeutic agent to treat patients infected with MERS-CoV, particularly in emergent cases. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effect of cinnamon on starch digestion was compared in dynamic and static models. • Higher starch hydrolysis was observed in the dynamic in vitro digestion model. • Cinnamon significantly curtailed starch digestion in the dynamic model only. • The dynamic model mimicked human gastric emptying, pH, luminal transit, and motility. Two in vitro digestion methods (static and dynamic) were applied in this study to investigate the effect of cinnamon on starch hydrolysis of rice pudding during in vitro digestion. The dynamic model simulated the major physiological processes including gastric emptying, motility, gastric acidification, and digestive secretions. The INFOGEST static method, which is widely adopted in digestion simulation studies, was conducted as a comparison. Two meals (i.e., rice pudding with and without cinnamon) were digested in the oral, gastric, and small intestinal phases in both models. Higher starch hydrolysis was observed in the gastric and intestinal phases in the dynamic model compared to the static model (p < 0.05). Furthermore, a significant inhibitory effect of cinnamon on starch hydrolysis was exclusively observed in the dynamic model. The difference could be attributed to the distinct gastric conditions including pH profiles, gastric emptying, and gastrointestinal motility in the two models. Our results indicated that the dynamic model could more closely estimate the effect of cinnamon on starch hydrolysis during digestion by simulating physiologically important gastrointestinal conditions in humans. Our findings also contribute to the growing body of scientific data suggesting that cinnamon may benefit hyperglycemic management due to its inhibitory effects on digestion enzymes. [ABSTRACT FROM AUTHOR]