Dual-responsive nanovaccine for cytosolic delivery of antigens to boost cellular immune responses and cancer immunotherapy.

Cancer vaccine contributing to the success of the treatment and prevention of tumors has attracted a huge attention as a strategy for tumor immunotherapy in recent years. A major challenge of cancer vaccine is to target cytosols of dendritic cells (DCs) in the lymph nodes (LNs) to enhance efficiency of antigen cross-presentation, which elicits high levels of cytotoxic T-lymphocytes to destruct tumor cells. Here, we address this issue by conjugating ovalbumin (OVA) to PEG-PCL using disulfide bond (-ss-), and the degradable pH-responsive polymer-PEI-PCL as delivery carrier. In addition, the mol ratio of PEG-PCL to PEI-PCL in the mixed micelles was tailored to deliver the OVA to LNs. Subsequently, CpG ODN1826, a TLR-9 agonist, was further introduced into a mixed micelle of 30 nm or less as a unique tumor vaccine. Importantly, the results demonstrated the mixed micelles with 1:1 mol of PCL-PEG and PCL-PEI can effectively migrate to distal LNs where antigen were efficiently captured by DCs, meanwhile, OVA was modified to the surface of mixed micelles via disulfide bonds (-ss-) for promotion efficiency of antigen cross-presentation. More surprisingly, combination of tumor vaccine with anti-PD-1, the therapy of ectopic melanoma (B16-OVA) and lung metastasis melanoma (B16-OVA) is excellent therapeutic effect. Taken together, our works offers a novel strategy for the cytosol delivery of antigens to achieve potent cancer immunotherapy.

Development of the computational antibiotic screening platform (CLASP) to aid in the discovery of new antibiotics.

Bacterial colonization of biotic and abiotic surfaces and antibiotic resistance are grand challenges with paramount societal impacts. However, in the face of increasing bacterial resistance to all known antibiotics, efforts to discover new classes of antibiotics have languished, creating an urgent need to accelerate the antibiotic discovery pipeline. A major deterrent in the discovering of new antibiotics is the limited permeability of molecules across the bacterial envelope. Notably, the Gram-negative bacteria have nutrient specific protein channels (or porins) that restrict the permeability of non-essential molecules, including antibiotics. Here, we have developed the Computational Antibiotic Screening Platform (CLASP) for screening of potential drug molecules through the porins. The CLASP takes advantage of coarse grain (CG) resolution, advanced sampling techniques, and a parallel computing environment to maximize its performance. The CLASP yields comprehensive thermodynamic and kinetic output data of a potential drug molecule within a few hours of wall-clock time. Its output includes the potential of mean force profile, energy barrier, the rate constant, and contact analysis of the molecule with the pore-lining residues, and the orientational analysis of the molecule in the porin channel. In our first CLASP application, we report the transport properties of six carbapenem antibiotics-biapenem, doripenem, ertapenem, imipenem, meropenem, and panipenem-through OccD3, a major channel for carbapenem uptake in Pseudomonas aeruginosa. The CLASP is designed to screen small molecule libraries with a fast turnaround time to yield structure-property relationships to discover antibiotics with high permeability. The CLASP will be freely distributed to enable accelerated antibiotic drug discovery.

Hybrid micelles codelivering shikonin and IDO-1 siRNA enhance immunotherapy by remodeling immunosuppressive tumor microenvironment.

Cancer immunotherapy is becoming an important option for malignant tumors treatment. Unfortunately, lacking intratumoral infiltration of cytotoxic T lymphocytes (CTLs) and immunosuppressive tumor microenvironment (ITM) remian primary barriers that immensely hamper its further clinical application. For boosting immune response and rebuilding the ITM, valid hybrid micelles (SK/siIDO1-HMs) delivering shikonin (SK) and IDO-1 knockdown siRNA (siIDO1) were conducted. SK/siIDO1-HMs had sufficient circulation time, favorable intratumoral accumulation and rapidly release in the cytoplasm. Importantly, SK was demonstrated to significantly elicit intratumoral accumulation of CTLs through inducing immunogenic cell death (ICD) of tumor cells. Moreover, siIDO1 downregulated the IDO-1-caused immunosuppression and restrained regulatory T lymphocytes (Tregs). In summary, SK/siIDO1-HMs displayed a remarkable potential for tumor therapy via triggering the ICD and moderating the IDO-1-triggered immunosuppression.

Cloning and characterization of steroid 5ß-reductase from the venom gland of Bufo bufo gargarizans.

Bufadienolides are the main active ingredients of Venenum Bufonis, which is a widely used traditional Chinese medicine secreted from parotoid gland and skin glands of Bufo bufo gargarizans. According to the transcriptome analysis, "cholesterol-bile acid-bufadienolidies pathway" was proposed as animal-derived bufadienolides biosynthesis pathway by us previously. In this pathway 3ß-hydroxysteroid dehydrogenase (3ßHSD) and steroid 5ß-reductase (SRD5ß) might be the key enzymes to convert the A/B ring to cis-configuration. Therefore, as the second report of our group, here we report the cloning of the full length of SRD5ß cDNA of B. bufo gargarizans (Bbg-SRD5ß) from the parotoid gland of B. bufo gargarizans for the first time, and site-directed mutagenesis was used to explored the character of Bbg-SRD5ß. Bbg-SRD5ß had an open reading frame of 981 bp and encoded 326 amino acids residues. The expression conditions of the recombinant Bbg-SRD5ß in E. coli BL21 (DE3) harbored with pCold-Bbg-SRD5ß was optimized as induction for 10 h at 15 °C with 0.1 mM IPTG. With NADPH as a cofactor, Bbg-SRD5ß can reduce the Δ4,5 double bonds of progesterone to generate dihydroprogesterone õwithout substrate inhibition effect. The catalytic rate of mutant type Bbg-SRD5ß-Y132G was 1.8 times higher than that of wild type Bbg-SRD5ß. Although Bbg-SRD5ß was almost unable to reduce the progesterone to dihydroprogesterone after mutation of V309, the affinity of enzyme with NADPH changed significantly. Bbg-SRD5ß is the key enzymes to convert the A/B ring of steroid to cis-configuration, and V309 is a key site affecting the binding affinity of enzyme with NADPH, and the mutation of Y132 can adjust the catalytic rate of Bbg-SRD5ß.

Two New Indole Alkaloids from Toad Venom of Bufo bufo gargarizans.

Two new indole alkaloids, Bufotenidine B (2) and Bufocarboline A (6), along with seven known indole alkaloids (1, 3-5, and 7-9) and three organic acids (10-12), were isolated from the water extract of toad venom. The structures of the new alkaloids were elucidated by extensive spectroscopic methods. The absolute configurations of 4, 6, and 8 were determined for the first time by electronic circular dichroism (ECD) calculations. The cytotoxic activity of all compounds was tested against human malignant melanoma cells A375 by the MTT method, and no antitumor activity was observed.

Multifunctional Nanoparticles Boost Cancer Immunotherapy Based on Modulating the Immunosuppressive Tumor Microenvironment.

Cancer immunotherapy has been a favorable strategy for facilitating antitumor immunity. However, immune tolerance and an ultimate immunosuppressive tumor microenvironment (ITM) are primary obstacles. To achieve the goals of remodeling the ITM and promoting cancer immunotherapy, a versatile nanoparticle codelivering shikonin (SK) and PD-L1 knockdown siRNA (SK/siR-NPs) was reported. SK/siR-NPs are demonstrated to tellingly induce the immunogenic cell death (ICD) of tumor cells, leading to increased dendritic cell maturation. Moreover, SK/siR-NPs can cause an efficacious inhibition of PD-L1, leading to enhanced cytotoxic T lymphocyte response to tumor cells. Most importantly, SK/siR-NPs can restrain lactate production via the downregulation of pyruvate kinase-M2 (PKM2) and eventually repolarize tumor associated macrophages (TAMs) from the M2-subtype to M1-subtype states. Meanwhile, SK/siR-NPs suppress regulatory T lymphocytes to fight with the ITM. Overall, the developed co-delivery system presents a significant potential for cancer immunotherapy through simultaneously inducing ICD, repolarizing M2-TAMs, and relieving PD-L1 pathway-regulated immune tolerance.

Non-canonical lipoproteins with programmable assembly and architecture.

The substrate promiscuity of an acyltransferase is leveraged to synthesize artificial lipoproteins bearing a non-canonical PTM (ncPTM). The non-canonical functionality of these lipoproteins results in a distinctive hysteretic assembly-absent from the canonical lipoproteins-and is used to prepare hybrid multiblock materials with precise and programmable patterns of amphiphilicity. This study demonstrates the promise of expanding the repertoire of PTMs for the development of nanomaterials with a unique assembly and function.

Seven novel variants expand the spectrum of RPE65-related Leber congenital amaurosis in the Chinese population.

Purpose: To screen RPE65 in 187 families with Leber congenital amaurosis (LCA). Methods: Sanger sequencing and/or targeted exome sequencing was employed to identify mutations in the RPE65 gene, and intrafamilial cosegregation analysis if DNA was available. In silico analyses and splicing assay were used to evaluate the variants' pathogenicity. Results: Genetic analysis revealed 15 mutations in RPE65 in 14 pedigrees, including one splice-site mutation, one frameshift mutation, three nonsense mutations, and ten missense mutations. Of the mutations identified in RPE65, seven are novel associated with LCA, including five missense variants (c.124C>T, c.149T>C, c.340A>C, c.425A>G, and c.1399C>G) and two indel (insertions or deletions) variants (c.858+1delG and c.1181_1182insT). In vitro splicing assay was performed to evaluate the functional impact on RNA splicing of novel mutations if two of three in silico analyses were predicated to be non-pathogenic at the protein level. Among these 15 variants, 14 were classified as 'pathogenic variants,' and a variant (c.124C>T) was 'variants with uncertain significance' according to the standards and guidelines of the American College of Medical Genetics and Genomics. Conclusions: Mutations in RPE65 were responsible for 11 of the cohort of 187 Chinese families with LCA, which expands the spectrum of RPE65-related LCA in the Chinese population and potentially facilitates its clinical implementation.

Simultaneous quantitative analysis of 11 flavonoid derivatives with a single marker in persimmon leaf extraction and evaluation of their myocardium protection activity.

An improved, reliable and comprehensive method for assessing the quality of the ethyl acetate extract from persimmon leaves (EAPL) and its commercial preparation, Naoxinqing (Brain and Heart Clear capsules), has been developed and validated. Based on HPLC-DAD-ESI-Q-TOF-MS analysis, myricetin-3-O-ß-D-galactoside (1), myricetin-3-O-glucoside (2), quercetin-3-O-ß-D-galactoside (3), quercetin-3-O-ß-D-glucoside (4), quercetin-3-O-(2″-O-galloyl-ß-D-galactoside) (5), quercetin-3-O-(2″-O-galloyl-ß-D-glucoside) (6), kaempferol-3-O-ß-D-galactoside (7), kaempferol-3-O-ß-D-glucoside (8), kaempferol-3-O-(2″-O-galloyl-ß-D-galactoside) (9), kaempferol-3-O-(2″-O-galloyl-ß-D-glucoside) (10), quercetin (11) and kaempferol (12) were identified from 15 batch samples. A HPLC fingerprint analytical method was established. All compounds, with the exception of compound 2, were simultaneously quantified by the single standard to determine multi-components (SSDMC) method, using kaempferol-3-O-ß-D-glucoside as the internal standard. The rate of analysis was found to be faster with the SSDMC method than with current acid hydrolysis method (Pharmacopoeia of the People's Republic of China 2015 edition) and the results were more intuitive and reliable. Three-dimensional principal component analysis revealed that there were similar characteristics in persimmon leaf from same district. Analysis of the myocardial cell protection activity of 11 monomeric compounds showed that compounds 12, 11 and 10 were the main active ingredients that produce pharmacologic functions in EAPL. Among these compounds, the bioactive constituent of myricetin-3-O-ß-D-galactoside was determined for the first time in Diospyros khaki. Thus, we have established an effective assessment method that can be applied to the comprehensive quality evaluation of EAPL extract and Naoxinqing capsule.

Multistage delivery of CDs-DOX/ICG-loaded liposome for highly penetration and effective chemo-photothermal combination therapy.

Nanoparticles (NPs) have proven to be effective drug carriers in diagnosis and therapy of cancer. But, they faced a contradictory issue that NPs with large size appear weak tumor penetration, meanwhile small size resulted in poor tumor retention. Herein, we fabricated doxorubicin conjugated carbon dots (CDs-DOX) and indocyanine green (ICG)-loaded liposomes (ICG-LPs) named CDs-ICG-LPs using a modified reverse phase evaporation process, and with high incorporation in the aqueous core. The CDs-ICG-LPs exhibited good monodispersity, excellent fluorescence/size stability, and consistent spectra characteristics compared with free ICG or DOX. Moreover, the CDs-ICG-LPs showed higher temperature response, faster DOX release under laser irradiation. In the meantime, the fluorescence of DOX and ICG in CDs-ICG-LPs was also visualized for the process of subcellular location in vitro. In comparison with chemo or photothermal treatment alone, the combined treatment of CDs-ICG-LPs with laser irradiation synergistically induced the apoptosis and death of DOX-sensitive HepG2 cells. In vivo antitumor activities demonstrated CDs-ICG-LPs could reach higher antitumor activity compared with CDs-DOX and ICG-LPs for H22 tumor cells, and suppressed H22 tumor growth in vivo. Notably, no systemic toxicity occurrence was observed after repeated dose of CDs-ICG-LPs with laser irradiation. Hence, the well-defined CDs-ICG-LPs exhibited great potential in targeting cancer imaging and chemo-photothermal therapy.

Cloning, prokaryotic expression and function of the Bufo bufo gargarizans 3ß-hydroxysteroid dehydrogenase (3ßHSD) gene.

Bufadienolides, one kind of steroids, are the major active component secreted by ear-side gland of Bufo species. Preliminary studies on high-throughput transcriptome sequencing about B. bufo gargarizans showed that the expression of 3ß-Hydroxysteroid dehydrogenase (3ßHSD) in ear-side gland was nearly 20 times higher than that in liver. The enzyme 3ßHSD is an essential step in the biosynthesis of steroid such as progesterone, estrogens and androgens in steroidogenic tissues. Accordingly, 3ßHSD is probably an important enzyme involved in the biosynthesis of bufadienolides. In this study, Bbg-3ßHSD cDNA was cloned from the ear-side gland of B. bufo gargarizans. Genetic engineering techniques were used to construct a recombinant prokaryotic fusion expression plasmid pCOLD-Bbg3ßHSD which was introduced into E. coli BL21 for prokaryotic expression. Bbg-3ßHSD has an open reading frame (ORF) of 1134 bp and encodes 377 amino acid residues. The speculated protein molecular weight is 42.8 kDa and its theoretical isoelectric point is 8.68. Amino acid sequence homologous analysis showed that Bbg-3ßHSD was highly homologous to the 3ßHSD protein of other species. Phylogenetic tree showed the highest similarity between Bbg-3ßHSD and 3ßHSD from Rana rugosa. The optimized expression of recombinant Bbg-3ßHSD were achieved by inducing with 0.1 mmol L-1 IPTG at 15 °C for 20 h. Enzymatic activity in vitro shows that pregnenolone and dehydroepiandroesterone could be 3ß-oxidized by Bbg-3ßHSD when NAD+ was used as the coenzyme. Enzymatic properties showed that the optimum reaction temperature of recombinant Bbg-3ßHSD was 40 °C, the optimum pH was 8.5, and the optimum coenzyme concentration was 1.5 mmol L-1.

A new indole alkaloid from the traditional Chinese medicine Chansu.

A new indole alkaloid N'-formylserotonin (1), along with five known indole alkaloids N'-methylserotonin (2), 5-hydroxy-1H-indole-3-carbaldehyde (3), N-acetylserotonin (4), 6-hydroxy-1-oxo-3,4-dihydro-ß-carboline (5), and bufoserotoin C (6), were isolated from the water extract of traditional Chinese medicine Chansu. Their structures were elucidated on the basis of spectral analyses. The cytotoxicities of 1-6 against human lung adenocarcinoma epithelial cells A549 were tested using the MTT method. Compound 6 exhibited stronger cytotoxic effect than 5-FU, and 1-5 showed no cytotoxic effects. Bufoserotonin C is one of the cytotoxic components in water-soluble extract of Chansu.

A New Indole Alkaloid from the Toad Venom of Bufo bufo gargarizans.

A new indole alkaloid named bufobutarginine (1), along with three known bufotenines, namely, serotonin (2), bufotenidine (3), and bufotenine (4), were isolated from the water extract of toad venom. Their structures were elucidated by spectral methods. This is the first time that arginine has been found to be involved in the biosynthesis of bufotenines in parotid of toad. The cytotoxic activities of these compounds have been assayed against A375 and A549 cell lines by the MTT method; however, they showed no cytotoxic activities.

A new thiaziedione from the fruits of Xanthium sibiricum.

A novel sulphur-containing compound named xanthiazinone (1) was isolated from the ethanolic extract of the fruits of Xanthium sibiricum, along with four known compounds, xanthiazone (2), xanthiside (3), xanthienopyran (4) and 5-hydroxypyrrolidin-2-one (5). Their structures were determined on the basis of spectroscopic techniques.