Latest ArticlesIn recent years, the biopharmaceutical industry has grown rapidly, and the market size of monoclonal antibody drugs has increased significantly. Accurate structural characterization and quality control are the supporting technologies for the development of monoclonal antibody drugs. As a significant post-translational modification of antibody drugs, glycosylation has an important influence on its efficacy, stability, and immunogenicity. The existing literature usually uses liquid chromatography-mass spectrometry to perform major glycosylation modifications of monoclonal antibody drugs. Characterization, there are few studies on low-abundance glycosylation, but the characterization and control of low-abundance glycosylation cannot be ignored. In this study, we have established a qualitative and quantitative analysis technology for N-glycans based on RapiFluor-MS reagent-labeled monoclonal antibody drugs. This method has a short sample processing time and high sensitivity. It can not only characterize the main glycoforms of three monoclonal antibody drugs (adalimumab, bevacizumab, and trastuzumab) but also can quantify low-abundance N-glycans. The results of the study showed that the main glycoforms specified in the Pharmacopoeia could be detected in different batches of monoclonal antibody drugs, but the content of N-glycans in different batches of samples is not identical. After that, we analyzed the N-glycans connection sites and glycoforms at the intact glycopeptide level, further enriching the N-glycans structure information of the monoclonal antibody. The qualitative and quantitative analysis technology of N-glycans based on RapiFluor-MS reagent-labeled monoclonal antibody drugs can realize the in-depth characterization and control of glycosylation modification of monoclonal antibody drugs.
A fast and sensitive UPLC-MS/MS method was established for the direct quantification of insulin aspart in human plasma. The plasma samples were extracted by solid phase extraction (SPE), an ESI ion source was used and operated in the positive ion mode with multiple reaction monitoring (MRM). Bovine insulin was chosen as internal standard and the chromatographic separation of insulin aspart was performed on Waters ACQUITY UPLC CSH C18 column (50 mm×2.1 mm, 1.7 μm). A mixture of acetic acid aqueous solution and acetonitrile with acetic acid at a flow rate of 0.6 mL·min-1 in gradient elution mode was employed as mobile phase. We found that the method was validated over the range of 0.200-10.0 ng·mL-1 for insulin aspart and showed excellent linearity. The intra-and inter-assay accuracy and precision were below 14.5% and the recovery was 36.7%-41.7% over the three concentration levels evaluated. The UPLC-MS/MS method was selective, accurate, sensitive and robust, and the method was successfully applied in supporting the pharmacokinetic research of two insulin aspart injections (Test Product and NovoRapid?) in heathy male subjects. This clinical trial was approved according to the Ethics Committee of West China Hospital, Sichuan University (2017 Clinical Trial (Western Medicine) Approval (148)).
Deamidation is one of the most common degradation impurities in protein and peptide drugs. The deamidation of glutamine and asparagine in the protein sequence can lead to changes in the chemical and biological properties of the protein. However, the rutine trypsin-based pretreatment process can significantly increase the artificial deamidation impurities during the digestion process, resulting in high determination level. In this study, after optimizing the conditions of Glu-C enzymatic hydrolysis, we obtained the best enzymatic conditions under acidic condition and the artificial deamidation impurities significantly reduced in digestion process, identified the deamidation site (N48). Through the methodological investigation and comparison of the measurement results of different methods, the specificity, reproducibility and accuracy of the method are verified. The method established in this research has laid a solid foundation for the accurate determination of deamidation impurities in cobratide and its similar protein peptide biochemical drugs.
Dendritic cells (DCs) are the most powerful and professional antigen-presenting cells (APCs) known at present. They play vital roles in the initiation and regulation of immune responses in body. Therefore, DC-based vaccine delivery system has gradually become a hotspot of basic scientific research and clinical treatment. DCs can be loaded with whole-cell antigens, nucleic acids, peptides, proteins (such as neoantigens) and nanoparticles to induce specific cellular immune responses and humoral immune responses after antigen processing, presentation and targeting delivery in vivo for the prevention and treatment of various diseases including cancers and microorganism infections. Vaccine-based on this technique is called dendritic cell (DC) vaccines. Great process in DC vaccines has been achieved in recent years. Therefore, we reviewed the characteristics of DC, types of DC vaccines and their clinical research progress in this paper.
Depression was a complex and difficult to regulate disease, which was closely related to purinergic system and purine metabolism disorder. Although there had been studies to improve depression by regulating purinergic system, the mechanism of action was complex and needed to be sorted out. Recently, a large number of studies had found that the addition of exogenous purine metabolites adenosine, inosine and guanosine had a significant antidepressant effect, indicating that regulating the level of purine substances in purine metabolism could also improve depression, which was of great significance to the further study of the pathogenesis and treatment of depression. In view of this, this study reviewed the relationship between purinergic system or purine metabolism and depression, in order to provide a reference for the further study of the pathogenesis of depression.
As a pleiotropic cytokine, interleukin-6 (IL-6) participates in many physiological activities in vivo. IL-6 plays an important role in the physiology and pathology of chronic inflammation, autoimmune diseases, tumors and other diseases through diverse mechanisms. At present, inhibitors targeting IL-6/IL-6R have been shown to improve treatments for some inflammatory diseases such as rheumatoid arthritis and systemic juvenile idiopathic arthritis. IL-6 binds to a specific receptor to activate the downstream JAK/STAT3 signaling pathway. However abnormally activated STAT3 often appears in various types of malignant tumors and participates in the occurrence and development of tumors. In addition, studies have shown that IL-6 is a key factor in the cytokine storm associated with COVID-19 patients. The physiological participation of IL-6/STAT3 pathway in complex diseases makes this pathway become a research hotspot for drug discovery. Therefore, we summarize the latest research progress of small molecular inhibitors on IL-6/STAT3 signaling pathway, in order to provide a reference for the development of IL-6/STAT3 related drug in the future.
The paper aims to compare the protective effect of Salvia miltiorrhiza and Anemarrhena asphodeloides on AD cell model and investigate its protective mechanism by cell metabolomics platform. AD cell model was established by the abnormal phosphorylation of Tau protein in SH-SY5Y cells induced by okadaic acid. The protective effect of the extract of Salvia miltiorrhiza and Anemarrhena asphodeloides on the model was evaluated by cell proliferation-toxicity experiment. The metabolomics platform was used to study the efficacy of Salvia miltiorrhiza and Anemarrhena asphodeloides comprehensively, explore the potential biomarkers related to AD and the effect of drugs on the potential biomarkers. Salvia miltiorrhiza extract had a certain protective effect on the AD model (P < 0.05), while the Anemarrhena asphodeloides extract had no significant protective effect (P > 0.05). 45 significant differential metabolites and the related 12 metabolic pathways were identified using UHPLC-QTOF/MS platform, which were related to the AD cell model. After administration of Salvia miltiorrhiza extract, 30 different metabolites appeared callback, while after intervention of Anemarrhena asphodeloides extract, 7 metabolites appeared callback. The results showed that the extracts of Salvia miltiorrhiza and Anemarrhena asphodeloides had certain protective effects on the AD cell model with Tau protein abnormal phosphorylation, but Salvia miltiorrhiza had more extensive targets and could significantly improve the cell viability. The mechanism may be related to the regulation of the metabolic pathways of AD cell model induced by okadaic acid.
Kidney injury and decreased chemosensitivity of tumor cells are obstacles with cisplatin (CDDP) chemotherapy. Down-regulation of the organic cation transporter 2 (OCT2) and multidrug resistance-associated protein 2 (MRP2) is a key means to alleviate CDDP-induced kidney injury and increase chemosensitivity. Astragaloside IV (AS IV) is obtained from the well-known traditional Chinese herb Astragalus membranaceus. This study explored the role of AS IV in preventing kidney injury and enhancing the antitumor effect of CDDP by suppressing OCT2 expression in kidney and MRP2 in tumors. This project was reviewed and approved by the Animal Ethics Committee of the First Hospital of Jilin University. The effects of AS IV on CDDP inhibition of tumor growth and promotion of apoptosis were assessed in Lewis lung tumor (LLC)-bearing mice by H&E and TUNEL staining. Kidney injury was assessed by serum biochemical parameters and H&E staining. We used Western blotting and immunohistochemistry assays to detect OCT2 and MRP2 expression in kidney and tumor. The concentration of CDDP in kidney and tumor was measured by HPLC-MS/MS. AS IV enhanced CDDP chemosensitivity by increasing tumor cell apoptosis and slowing tumor growth, and decreased kidney injury as evidenced by lower blood creatinine (Cr) and blood urea nitrogen (BUN). Co-administration of AS IV suppressed MRP2 overexpression induced by CDDP in tumor tissues and may be an important mechanism for enhancing CDDP chemosensitivity. Moreover, AS IV reduced CDDP-induced kidney injury in mice along with suppression of OCT2 expression in kidney. The concentration of CDDP was increased in tumor but decreased in kidney. In total, AS IV not only enhanced the antitumor effect of CDDP by suppressing MRP2 expression in tumor cells, but also decreased kidney injury induced by CDDP. The results provide new insight into the combined use of a chemotherapy drug and natural ingredients to treat cancer.
In order to study the contraindications of the compatibility of Flos Genkwa-Radix et Rhizoma Glycyrrhizae, in this study, the solubilizing and poisoning essence were explored. In this experiment, chromatographic assay, field emission scanning electron microscopy, MTT cytotoxicity evaluation, and other methods were used to study the main chemical components, morphology and toxicity of the ethyl acetate part of Flos Genkwa and its co-decoction with glycyrrhizic acid, in order to clarify Flos Genkwa-Radix et Rhizoma Glycyrrhizae incompatibility provides a new idea for the research on incompatibility of Flos Genkwa-Radix et Rhizoma Glycyrrhizae. The results showed that after co-decoction of the ethyl acetate part of Flos Genkwa with glycyrrhizic acid, high performance liquid chromatography (HPLC) detected the dissolution of the toxic component yuanhuacine of 54.8%, while yuanhuacine chromatographic peak was not detected in the Flos Genkwa ethyl acetate part of the single decoction. The increase of co-decoction dissolution rate was observed by scanning electron microscopy, and it was found that glycyrrhizic acid uniformly dispersed the fat-soluble components of Flos Genkwa into nano-scale particles, which improved the solubility and stability in the solution. Furthermore, the results of cytotoxicity evaluation showed that the survival rate of cells decreased after co-decoction, 4', 6-diamidino-2-phenylindole (DAPI) staining also gave the same results. In summary, the co-decoction of the ethyl acetate part of Flos Genkwa with glycyrrhizic acid promotes the dissolution of the toxic component yuanhuacine, and makes the part form uniformly distributed nanoparticles, which is conducive to the absorption of the ingredient and increases the toxicity.
Influenza A virus (H1N1) seriously affects the health of human and disrupts the development of global economic. The antimicrobial peptide urumin specifically binds to the conserved stem of the hemagglutinin (HA) protein of H1N1 virus, but its binding site and the mechanism of action are not clear. In this study, we investigated the possible binding sites and key amino acids for the interaction of urumin with HA protein by molecular docking and enzyme-linked immunosorbent assay (ELISA) experiments, suggesting that HA residues His32 (HA1), Asp19 (HA2), and Trp21 (HA2) are the key residues for the interaction of HA with urumin. Urumin's Arg4, Asn9, and Cys16 were associated with HA protein residues Asp19 (HA2), Trp21 (HA2), His32 (HA1), and Asn53 (HA2) form hydrogen bonding interactions, and Trp12 forms an aromatic π-stacking interaction with His32 (HA1) of HA, these interactions maintain the binding of urumin to HA protein. Wild-type HA and its alanine mutant[alanine substitutions His32 (HA1), Asp19 (HA2), and Trp21 (HA2)] were expressed in 293T cells. ELISA experiments showed that the affinity ability of urumin with HA wild-type was significantly higher than that of HA alanine mutant, suggesting that His32 (HA1), Asp19 (HA2), and Trp21 (HA2) may be the key residues for HA to interact with urumin. This study provides a theoretical and experimental basis for further modification and application of urumin.