Latest ArticlesMonoclonal antibodies (mAbs) have been widely used as therapeutic drugs for treating diseases such as cancers and auto-immune diseases. When using an IgG4 isotype, one of the challenges is the instability of its hinge which is prone to Fab-arm exchange (FAE). The hinge sequence of a wild type IgG4 is -CPSC-, however, a single point mutation S228P from -CPSC-to -CPPC-can effectively diminish FAE, thereby improving hinge stability of the IgG4 molecule. Sintilimab is the fully human anti-PD-1 monoclonal antibody designed and developed for immuno-oncology, in which serine 228 in the hinge was engineered to proline to mitigate FAE. In this study, LC-MS is used to study hinge stability of sintilimab in both in vitro (PBS and human serum) and in vivo (SCID mouse) studies. The studies demonstrate that LC-MS is a fast and simple way to monitor for the occurrence of FAE in vitro and in vivo, and FAE can be eliminated by antibody engineering with a single point mutation.
An ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) method was developed to evaluate the chemical consistency of triterpene acids in ethanol extracts of Poria and acetic ether extracts thereof. First, high resolution mass spectrometry data were obtained with Full scan mode, by comparing with MS data from the reference compounds and literatures, a total of 23 components were unequivocally or tentatively identified in ethanol extracts and acetic ether extracts thereof. Then, a mimic multiple reaction monitoring (mMRM) mode was established using UPLC-QTOF-MS/MS to quantify the triterpene acids in ethanol extracts and acetic ether extracts thereof. Eleven components were absolutely quantified with reference compounds, while 12 components without reference compounds were relatively quantified with peak areas, the transfer and enrichment rate of triterpene acids during liquid-liquid extraction were calculated. It was found all of the 23 triterpene acids identified in Poria ethanol extracts could be transferred into acetic ether extracts with high transfer and enrichment rate. The present study provides not only scientific evidence for further extraction of triterpene acids in Poria by acetic ether, but also an approach for comprehensive evaluation of the chemical consistency of herbal medicine extracts before and after the liquid-liquid extraction.
Near-infrared spectroscopy (NIRS) combined with chemometrics can achieve rapid detection in process analysis. After variable selection, the redundant information is effectively removed and the characteristic variables related to the response values are selected. Compared with global model, the complexity is significantly reduced and the prediction accuracy is also improved. In this study, near-infrared spectroscopy analysis combined with different variable selection methods was applied to achieve the rapid detection of baicalin in the extraction process of Scutellaria baicalensis. Data sets were divided based on sample set portioning based on joint x-y distance (SPXY) method. Competitive adaptive weighted resampling method (CARS), random frog (RF) and successive projections algorithm (SPA) were applied to variable selection. Partial least squares (PLS) models were constructed based on above three methods, and the prediction results were compared. After CARS, RF and SPA method, 92, 10 and 17 variables were screened out respectively. According to the performance of the models, CARS method is found to be more effective and suitable than RF and SPA. Furthermore, the characteristic variables selected by CARS method have a better correspondence with the chemical structure of baicalin. The root mean square error (RMSEC) of the calibration set and the root mean square error (RMSEP) of the prediction set are 0.528 2 and 0.720 2 respectively. Compared with the global PLS model, the correlation coefficient of the calibration set (Rc) is increased to 0.979 9 from 0.917 0, and the relative standard errors of prediction (RSEP) is reduced to 5.59% from 10.58%.
Using the lipidomics method based on UHPLC-Q-Exactive Orbitrap/MS, the change of phospholipid metabolism in lung tissue of mice induced by lipopolysaccharide (LPS)-induced acute lung injury was analyzed to observe the regulation of abnormal lipids by Jiegeng Decoction and to explore the regulation effect of Jiegeng Decoction on LPS-induced acute lung injury. The lung tissue samples from control group, model group, dexamethasone (positive drug) group, and Jiegeng Decoction group were collected and the lipid components of the sample were extracted. All procedures over mice were performed in accordance with the Guidelines for Care and Use of Laboratory Animals of Nanjing University of Chinese Medicine, and the experiments were approved by the Animal Ethics Committee of our university. The lipidomics technique of UHPLC-Q-Exactive Orbitrap/MS was used to study change of phospholipids in lung tissue of each group. LPS induced acute lung injury in mice with metabolic abnormalities of phospholipids, the specific performance of the PC was significantly upregulated, phosphatidyl ethanolamine (PE), phosphatidyl glycerol (PG), phosphatidyl serine (PS), phosphatidylinositol (PI) and other metabolic disorders, Jiegeng Decoction have a certain role in these phospholipids. LPS-induced acute lung injury caused disturbances of phospholipid in vivo, and Jiegeng Decoction regulates metabolic phospholipids.
This study was designed to prepare a novel lipid bilayer coated hollow mesoporous silica nanocarrier for co-delivery of gene drugs and chemotherapeutic drugs to enhance the inhibitory activity of antitumor drugs in hepatoma cells. Hollow mesoporous silica was synthesized by modified StÖber method. Lipid-fusion principle was used to prepare lipid-hollow co-loaded doxorubicin (DOX) and miR-375 (LHMSN-DOX/miR-375). Meanwhile, the morphology, particle size, surface potential, drug loading and release were characterized in vitro. The inhibition of cell proliferation, cell migration and invasion was then evaluated. The results indicated that the core-shell structure of LHMSN-DOX/miR-375 was clear with an intact outer lipid membrane and an ordered internal HMSN mesoporous structure. The drug release amount was pH responsive while the drug was rapidly released under simulated intracellular acidic conditions relative to normal physiological environment. Compared with free DOX, LHMSN-DOX/miR-375 can deliver DOX and miR-375 to liver cancer cells and inhibit the proliferation, migration and invasion of cells more effectively.
The objective of this paper was to establish a level A in vitro-in vivo correlation (IVIVC) for goserelin acetate extended release microspheres for injection. Three kinds of goserelin acetate microspheres with different release rates were prepared and the critical physicochemical properties, such as drug loading, particle size, glass transition temperature and morphology were characterized. In vitro dissolution test of the prepared goserelin acetate microspheres was performed using sample-and-separate method at 45℃ in 5% (v/v) methanol. The morphology of the microspheres and the molecular weight of poly (lactic-co-glycolic acid) (PLGA) of the prepared goserelin acetate microspheres were investigated to research the release mechanism of microspheres. The plasma concentration of goserelin was detected after intramuscular injection of goserelin acetate microspheres to SD rats, and correlated with the in vitro release profiles after processing by percent AUC method. The pharmacokinetic experimental protocol of goserelin acetate microspheres for injection in SD rats was approved by the Animal Ethics Committee of Shandong Luye Pharmaceutical Co., Ltd. The results indicated that the developed sample and separate method was able to detect differences in the release characteristics of the prepared goserelin acetate microspheres, and the in vitro-in vivo correlation of goserelin acetate microspheres was excellent (r > 0.98) and had good predictive ability in SD rats.
Gentiana section Cruciata (Gentianaceae) is a medicinally important section of herbs, including Chinese traditional medicine Gentianae Macrophyllae Radix and Tibetan herb Jieji. Here, we assess the taxonomic significance using mtDNA nad1/b-c and nad5/d-e sequence data. A total of 144 nad1/b-c and nad5/d-e sequences from 11 species within Gentianaceae were obtained, including 138 sequences from 10 species within Gentiana section Cruciata and 6 sequences from Halenia elliptica (outgroup). The results showed that mtDNA nad1/b-c has species-level resolution within the section of Cruciata, i.e. the variable in the position 45 "C" could be used as a stable marker locus to distinguish G. robusta from other taxa; the variable in the position 352 and 353 "GA" could distinguish G. crassicaulis and G. tibetica from other taxa within the section. Intraspecies genotype variability was detected in nad1/b-c sequences of G. officinalis and G. siphonantha, respectively. These genotypes could be used as potential DNA barcode. In addition, intraspecies genotype variability was detected in nad5/d-e sequences of G. macrophylla, G. officinalis and G. siphonantha, respectively. Based on the stable marker locus, a species-specific PCR protocol was developed using the primer PF to identifying G. robusta in the section. This study could expand the understanding of the diversity of mtDNA nad1/b-c and nad5/d-e in the genus Gentiana, and provide the essence for the species identification within Gentiana section Cruciata.
Allium chinense belongs to the genus Alliums of the lily family. It can be used both as medicine and food. To date, the phylogenetic relationship of Allium species have not be resolved completely. Furthermore, there has been a lack of DNA barcode to distinguish closely related species. In this study, the complete chloroplast genome of A. chinense was obtained using next generation DNA sequencing and bioinformatic analysis, and compared with that from other Allium species. The genome is a circular molecule of 152 525 bp with a typical quadripartite structure. Genome annotation identified a total of 116 genes, including 81 protein-coding genes, 31 tRNA genes, and 4 rRNA genes. Analyses of sequences from six Allium species showed that the most diverse regions are found in the protein coding regions such as ndhA and ycf1 genes, and in the intergenic regions, such as ps16-trnQ, trnT-trnF, ndhF-rpl32, rpl32-trnL and rpl16-rps3. A phylogenetic tree was constructed using 58 protein coding sequences from 53 species. All branches showed strong support with bootstrap scores reaching 66%-100%, except those for the Lilium and Paris. Our results suggest that the completed chloroplast genome could solve the classification problems of these species. Using EcoPrimer software, we identified seven markers from the chloroplast genomes, which can be used to differentiate congeneric species. In summary, we have sequenced the complete chloroplast genome of A. chinense, carried out phylogenetic analysis and identified a series of genus specific DNA barcode sequences. The results have laid the foundation for the systematical determination of the phylogenetic relationship of Allium species and the differentiation of species using the genus specific primers.
Based on the integrity and systematicness of Chinese medicine, the components preparation simplifies the complex problems of multi-components of Chinese medicine, provides an effective and feasible model for the development of Chinese medicine preparation. It has become a hot topic in the research of prep-aration, and is also considered as one of the effective ways to realize the modernization of Chinese medicine. Based on the previous research on multi-components and the work of our research group, the research frontiers of multi-components are elucidated, including the properties and characterization techniques of components, the construction of components release unit, and the multiple drug delivery system. The purpose of this paper is to explore the technical basis and key problem of components preparation, and then bring some inspiration and thought to the relevant researchers.
The discovery and verification of components are prerequisites for developing of component preparations. The molecular docking technique and pharmacodynamic activity evaluation provide effective methods for the discovery and verification of the representative components of Chishao terpene glucoside components (CSTGCS) against ischemia and hypoxia injury. The chemical constituents of CSTGCS were analyzed qualitatively by UPLC-TOF/MS/MS. Main chemical constituents were docked with key receptor proteins of myocardial ischemia to preliminarily screen anti-ischemia active ingredients, and screening for main active ingredients with Libdockscore. Then a H9c2 cell hypoxia injury model was established, and creatine kinase (CK), lactate dehydrogenase (LDH), superoxide dismutase (SOD), malondialdehyde (MDA) were determined to screen the representative combinations in CSTGCS. In addition, apoptosis index, apoptotic protein expression and mitochondria-associated mRNA levels were determined to verify the inhibition of the representative components (RCS) on the apoptosis of hypoxic cells. Eventually, the representative components of CSTGCS were determined. The results showed that paeoniflorin, albiflorin, benzoyl paeoniflorin and oxypaeoniflorin were considered to be the main active components because of their high matching with target proteins (4TWT, 3O4O, 4KZN, 1M9J) in space and energy. There was no statistical difference in regulating CK, LDH, SOD, MDA levels and maintaining mitochondrial function as well as inhibiting cell apoptosis between CSTGCS group and RCS group (paeoniflorin + albiflorin + benzoyl paeoniflorin combination). Therefore, paeoniflorin, albiflorin and benzoyl paeoniflorin were selected as the most representative ingredients of CSTGCS against ischemia and hypoxia injury, providing a basis for the overall properties of the components and formulation of CSTGCS.