How far have we reached in development of effective influenza vaccine?

DEVELOPMENT OF REASSORTANT INFLUENZA VACCINES: CLASSICAL REASSORTMENT OR REVERSE GENETICS?

An important feature of influenza vaccines, which distinguishes them from other immunobiological preparations, is that they have no fixed composition. Due to the constant influenza virus antigenic variability, production facilities require timely supply with relevant vaccine strains undoable due to the lack of proper method for the convenient, rapid and uninterrupted development of vaccine strains. Among the licensed influenza vaccines, classical inactivated and live influenza vaccines hold a special place. They are based on reassortant vaccine strains obtained by crossing currently circulating influenza virus with the so-called donor strain (cold-adapted attenuation donor for live influenza vaccines or high yield donor for inactivated vaccines). Vaccine strains for licensed live attenuated influenza vaccines are reassortants with the so-called 6:2 genome formula two genes encoding hemagglutinin and neuraminidase (HA and NA) belong to the current epidemic virus, and six genes encoding internal proteins (PB2, PB1, PA, NP, M and NS) to cold-adapted master donor virus. There is a very limited number of donors of attenuation. In Russia, there are cold-adapted viruses A/Leningrad/134/17/57 (H2N2) and B/USSR/60/69; in the USA (MedImmune) there are viruses A/Ann Arbor/6/60ca (H2N2) and B/Ann Arbor/1/66ca. MedImmune produces vaccine strains using reverse genetics technique. For other countries, this approach for obtaining vaccines is limited due to the need to purchase a license from the patent holders. In Russia, genetic manipulations with strains for the seasonal live influenza vaccine are not yet allowed; reassortants for the Russian live influenza vaccine are created only by classical reassortment in embryonated chicken eggs. Vaccine candidates for the inactivated influenza vaccine are prepared by the classical reassortment method, the requirements for them are more flexible and allow to use diverse genes combinations from wild type virus and master donor virus. High-yielding viruses such as A/PR/8/34 (H1N1), A/Texas/1/77 (H3N2), B/Lee/40 and some others are used as donors of internal genes. Unfortunately, the classical reassortment method does not always allow to promptly obtain a reassortant virus with a 6:2 genome formula. This is hindered by a number of reasons, ranging from the unique properties of a certain epidemic virus ending up with the constellation of genes. The reverse genetics method based on plasmids is an alternative approach to create reassortant vaccine strains allowing to reliably and quickly obtain reassortant viruses of a set 6:2 genome formula. However, this method also has certain weaknesses. This review discusses the advantages and disadvantages of development of conventional influenza vaccine candidates by reverse genetics and classical reassortment in developing chick embryos.

Matrine impedes colorectal cancer proliferation and migration by downregulating endoplasmic reticulum lipid raft associated protein 1 expression

Matrine exhibits anti-tumor effect on the proliferation and invasion of colorectal cancer (CRC) cells by reducing the activity of the p38 signaling pathway. However, these studies were limited because the underlying mechanism by which matrine inhibited CRC progression remained unclear. In this study, we provided for the first time that endoplasmic reticulum lipid raft associated protein 1 (Erlin1) is a novel target of matrine. Erlin1 was significantly upregulated in tumors and its knockdown suppressed the proliferation and migration of CRC cells, while its overexpression promoted CRC cell growth and migration. Furthermore, Erlin1 overexpression promoted inhibited apoptosis. Importantly, matrine treatment could reverse the oncogenic function of Erlin1 on CRC cell proliferation and migration. When Erlin1 was knocked down, matrine exhibited a more obvious anti-tumor effect in CRC cells. Partly due to this, matrine functions as an important anti-tumor drug and the results discovered here may clarify the mechanisms of matrine application for CRC treatment. CRC patients with low expression of Erlin1 might be more suitable for the treatment of matrine. This study could promote the application of matrine to be a promising therapeutic strategy for CRC patients.

Matrine Combined with Mammalian Target of Rapamycin Inhibitor Enhances Anti-Tumor Efficacy of dendritic cell Vaccines in hepatocellular carcinoma

Dendritic cells (DCs), as the most important antigen-presenting cells, play a crucial role in T cell activation. The latest research showed that inhibition of the mammalian target of rapamycin (mTOR) could enhance DCs maturation, promoting antigen presentation. Matrine has been identified as one of the key alkaloids isolated from the roots of Sophora flavescens. In present study, we combined matrine and mTOR inhibitor KU0063794 to observe the DCs functions, especially the antigen presentation ability. DCs were activated by phosphate-buffered saline (PBS), lipopolysaccharide (LPS), LPS+KU0063794, LPS+Matrine, and LPS+KU0063794+Matrine. The surface markers in DCs, proliferation of T cells and cytokines were detected by flow cytometry, cell counting kit-8 (CCK-8) and enzyme-linked immunosorbent assay (ELISA), respectively. The lactate dehydrogenase (LDH) release test was used to detect the antitumor efficacy. The tumor growth curves were plotted by calculating tumor volume. The apoptosis was detected by Terminal-deoxynucleoitidyl Transferase-Mediated Nick End Labeling (TUNEL) method. Matrine combined with KU0063794 could enhance the maturity of DCs, T cells proliferation and cytokines secretion (P < 0.05). The cytotoxic T lymphocytes (CTL) killing efficacy of LPS+KU0063794+Matrine group was higher than other groups (P < 0.05). In vivo, the tumor weights and volumes in LPS+KU0063794+Matrine group were lower than other groups. The detections of tumor apoptosis were increased in LPS+KU0063794+Matrine group (P < 0.05). DC vaccine with mTOR inhibitor and matrine could significantly improve the efficacy of antitumor immunity in vitro and vivo. These findings illustrated that mTOR inhibitor and matrine, as two immunomodulators, could enhance DC activation and differentiation.

Shikonin induces cell autophagy via modulating the microRNA -545-3p/guanine nucleotide binding protein beta polypeptide 1 axis, thereby disrupting cellular carcinogenesis in colon cancer

Shikonin (SHK), a major component of shiverweed, was provided with anti-tumor effects via multiple targets and signal pathways. Nevertheless, the specific mechanism of its function in colorectal cancer (CRC) still needed to be further explored. The study was designed to examine the role of SHK in CRC and its specific mechanism on the cell tumor behavior of CRC. Collection of clinical samples was performed, and test of microRNA (miR)-545-3p and guanine nucleotide-binding protein beta polypeptide 1 (GNB1) in the samples was conducted; Selection of CRC cell line was exerted, and examination of miR-545-3p and GNB1 was performed; After treatment of shikonin (SHK), correlated plasmids were transfected, test of cell advancement was performed. Test of the protein of autophagy-correlated proteins light chain 3-II/light chain 3I and p63 was performed. The interaction of miR-545-3p with GNB1 was explored, and the action of SHK in vivo was tested. SHK repressed the advancement of SW480 cells with elevated apoptosis and autophagy and the cells quantities in G0/G1 phase. MiR-545-3p was elevated in CRC. SHK boosted miR-545-3p, repression of miR-545-3p or augmentation of GNB1 was able to turn around the function of SHK on CRC, and GNB1 was the target gene of miR-545-3p.All in all, SHK stimulates apoptosis and autophagy in CRC via miR-545-3p/GNB1 signaling axis, firstly demonstrating the regulatory mechanism of SHK in CRC via miR-545-3p/GNB1 axis.

The anti-fibrotic agent nintedanib protects chondrocytes against tumor necrosis factor-ɑ (TNF-ɑ)-induced extracellular matrix degradation

Osteoarthritis is an inflammatory disease of the musculoskeletal system characterized by damaged articular cartilage. Nintedanib is an oral triple kinase inhibitor with anti-fibrotic and anti-inflammatory properties. Thus, we hypothesized that nintedanib might exert a protective effect in chondrocytes and it could be meaningful to repurpose the drug for osteoarthritis. In this study, we aimed to investigate the potential effects of nintedanib on TNF-α-induced cellular injury in CHON-001 chondrocytes. The results show that nintedanib ameliorated TNF-α-induced reactive oxygen species (ROS) production and reduced glutathione (GSH) decrease. Nintedanib reduced the production of pro-inflammatory cytokines interleukin-6 (IL-6) and interleukin-1β (IL-1β) in TNF-α-induced CHON-001 chondrocytes. Nintedanib restored TNF-α caused decreased expression levels of Col II and sry-type high-mobility-group box-9 (SOX-9) in CHON-001 chondrocytes. Moreover, nintedanib ameliorated the TNF-α-caused impairment of protein kinase A/cAMP-response element-binding protein (PKA/CREB) signaling pathway as revealed by the decreased PKA RI expression and increased p-CREB in CHON-001 cells. Inhibition of PKA by H89 abolished the effects of nintedanib on SOX-9 and Col II expression. Taken together, nintedanib presented protective effects on TNF-α-induced oxidative stress, inflammation, and ECM damage in CHON-001 chondrocytes. Mechanically, the effect of nintedanib is associated with the PKA/CREB pathway. These data imply that the anti-fibrotic agent nintedanib may have a potential therapeutic application for osteoarthritis.

Human Plasma Metabolomics Identify 9-cis-retinoic Acid and Dehydrophytosphingosine Levels as Novel biomarkers for Early Ventricular Fibrillation after ST-elevated Myocardial Infarction

The relevant metabolite biomarkers for risk prediction of early onset of ventricular fibrillation (VF) after ST-segment elevation myocardial infarction (STEMI) remain unstudied. Here, we aimed to identify these imetabolites and the important metabolic pathways involved, and explore whether these metabolites could be used as predictors for the phenotype. Plasma samples were obtained retrospectively from a propensity-score matched cohort including 42 STEMI patients (21 consecutive VF and 21 non-VF). Ultra-performance liquid chromatography and mass spectrometry in combination with a comprehensive analysis of metabolomic data using Metaboanalyst 5.0 version were performed. As a result, the retinal metabolism pathway proved to be the most discriminative for the VF phenotype. Furthermore, 9-cis-Retinoic acid (9cRA) and dehydrophytosphingosine proved to be the most discriminative biomarkers. Biomarker analysis through receiver operating characteristic (ROC) curve showed the 2-metabolite biomarker panel yielding an area under the curve (AUC) of 0.836. The model based on Monte Carlo cross-validation found that 9cRA had the greatest probability of appearing in the predictive panel of biomarkers in the model. Validation of model efficiency based on an ROC curve showed that the combination model constructed by 9cRA and dehydrophytosphingosine had a good predictive value for early-onset VF after STEMI, and the AUC was 0.884 (95% CI 0.714–1). Conclusively, the retinol metabolism pathway was the most powerful pathway for differentiating the post-STEMI VF phenotype. 9cRA was the most important predictive biomarker of VF, and a plasma biomarker panel made up of two metabolites, may help to build a potent predictive model for VF.

Circular RNA Pvt1 oncogene (CircPVT1) promotes the progression of papillary thyroid carcinoma by activating the Wnt/β-catenin signaling pathway and modulating the ratio of microRNA-195 (miR-195) to vascular endothelial growth factor A (VEGFA) expression

Circular RNAs (circRNAs) have been reported to be involved in the progression of papillary thyroid carcinoma (PTC). However, the role of circular RNA Pvt1 oncogene (circPVT1) in PTC has rarely been reported. In this study, we aimed to investigate the function and mechanism of circPVT1 in PTC. The expression level of circPVT1, miR-195 and VEGFA were determined by reverse transcription‑quantitative PCR (RT‑qPCR). Fisher's exact test was used to analyze the correlation between circPVT1 expression and PTC clinical features. Cell Counting Kit-8 (CCK-8) and 5-Ethynyl-2'-deoxyuridine (EdU) staining assay and transwell assay were conducted to evaluate the cell proliferation, migration and invasion ability. Dual-luciferase reporter and Western blot assay were conducted for evaluating the correlation between miR-195 and circPVT1 or VEGFA. The results of RT-PCR showed that the expression level of circPVT1 was significantly upregulated in PTC tissues and cell lines. After downregulating circPVT1 expression in PTC cells, the abilities of cell proliferation, migration, and invasion were obviously suppressed, and the Wnt/β-catenin signaling pathway was also repressed. Besides, miR-195 could both bind to PVT1 and VEGFA, while PVT1 could promote the expression of VEGFA by binding to miR-195. Downregulation of VEGFA expression in PTC cells revealed weakened cell proliferation, migration, and invasion capacities, and restrained Wnt/β-catenin signaling pathway. Therefore, we demonstrated that circPVT1 could promote VEGFA expression by sponging miR-195. CircPVT1 could serve as a molecule sponge for miR-195 and mediate the ceRNA network to promote the expression of VEGFA, thus contributed to the malignant progression of PTC.

Efforts to Improve the Seasonal Influenza Vaccine

Seasonal influenza is an acute syndrome, principally involving the respiratory tract caused by influenza viruses that are globally present [...].

hFUT1-Based Live-Cell Assay To Profile α1-2-Fucoside-Enhanced Influenza Virus A Infection

Host cell surface glycans play critical roles in influenza virus A (IVA) infection ranging from modulation of IVA attachment to membrane fusion and host tropism. Approaches for quick and sensitive profile of viral avidity toward a specific type of host cell glycan can contribute to the understanding of tropism switching among different IVA strains. Here, we developed a method based on chemoenzymatic glycan engineering to investigate the possible involvement of α1-2-fucosides in IVA infections. Using a truncated human fucosyltransferase 1 (hFUT1), we created α1-2-fucosides in situ on host cells to assess their influence on the host cell binding to IVA hemagglutinin and the susceptibility of host cells toward IVA-induced killing. We discovered that the newly created α1-2-fucosides on host cells enhanced the infection of several human pandemic IVA subtypes either directly or indirectly. These findings suggest that glycan epitopes other than sialic acid should also be considered for assessing the human pandemic risk of this viral pathogen.