The natural stilbenoid (-)-hopeaphenol inhibits cellular entry of SARS-CoV-2 USA-WA1/2020, B.1.1.7 and B.1.351 variants

Antivirals are urgently needed to combat the global SARS-CoV-2/COVID-19 pandemic, supplement existing vaccine efforts, and target emerging SARS-CoV-2 variants of concern. Small molecules that interfere with binding of the viral spike receptor binding domain (RBD) to the host ACE2 receptor may be effective inhibitors of SARS-CoV-2 cell entry. Here we screened 512 pure compounds derived from natural products using a high-throughput RBD/ACE2 binding assay and identified (-)-hopeaphenol, a resveratrol tetramer, in addition to vatalbinoside A and vaticanol B, as potent and selective inhibitors of RBD/ACE2 binding and viral entry. For example, (-)-hopeaphenol disrupted RBD/ACE2 binding with a 50% inhibitory concentration (IC50) of 0.11 M in contrast to an IC50 of 28.3 M against the unrelated host ligand/receptor binding pair PD-1/PD-L1 (selectivity index = 257.3). When assessed against the USA-WA1/2020 variant, (-)-hopeaphenol also inhibited entry of a VSV{Delta}G-GFP reporter pseudovirus expressing SARS-CoV-2 spike into ACE2-expressing Vero-E6 cells and in vitro replication of infectious virus in cytopathic effect assays (IC50 = 10.2 M) without cytotoxicity. Notably, (-)- hopeaphenol also inhibited two emerging variants of concern originating from the United Kingdom (B.1.1.7) and South Africa (B.1.351) in both cytopathic effect and spike-containing pseudovirus assays with similar (B.1.1.7) or improved (B.1.351) efficacies over the USA- WA1/2020 variant. These results identify (-)-hopeaphenol and related stilbenoid analogues as potent and selective inhibitors of viral entry across multiple SARS-CoV-2 variants including those with increased infectivity and/or reduced susceptibility to existing vaccines. ImportanceSARS-CoV-2 antivirals are needed to supplement existing vaccine efforts and target emerging viral variants with increased infectivity or reduced susceptibility to existing vaccines. Here we show that (-)-hopeaphenol, a naturally-occurring stilbenoid compound, in addition to its analogues vatalbinoside A and vaticanol B, inhibit SARS-CoV-2 by blocking the interaction of the viral spike protein with the cellular ACE2 entry receptor. Importantly, in addition to inhibiting the early USA-WA1/2020 SARS-CoV-2 variant, hopeaphenol also inhibits emerging variants of concern including B.1.1.7 ("United Kingdom variant") and B.1.351 ("South Africa variant"), with improved efficacy against B.1.351. (-)-Hopeaphenol therefore represents a new antiviral lead against infection from multiple SARS-CoV-2 variants.

LMP2-DC Vaccine Elicits Specific EBV-LMP2 Response to Effectively Improve Immunotherapy in Patients with Nasopharyngeal Cancer / 生物医学与环境科学（英文）

Objective@#To evaluate the safety and effectiveness of a vaccine based on latent membrane protein 2 (LMP2) modified dendritic cells (DCs) that boosts specific responses of cytotoxic T lymphocytes (CTLs) to LMP2 before and after intradermal injection in patients with nasopharyngeal carcinoma (NPC).@*Methods@#DCs were derived from peripheral blood monocytes of patients with NPC. We prepared LMP2-DCs infected by recombinant adenovirus vector expressing LMP2 (rAd-LMP2). NPC patients were immunized with 2 × 10 @*Results@#We demonstrated that DCs derived from monocytes displayed typical DC morphologies; the expression of LMP2 in the LMP2-DCs vaccine was confirmed by immunocytochemical assay. Twenty-nine patients with NPC were enrolled in this clinical trial. The LMP2-DCs vaccine was well tolerated in all of the patients. Boosted responses to LMP2 peptide sub-pools were observed in 18 of the 29 patients with NPC. The follow-up data of 29 immunized patients from April, 2010 to April 2015 indicated a five-year survival rate of 94.4% in responders and 45.5% in non-responders.@*Conclusion@#In this pilot study, we demonstrated that the LMP2-DCs vaccine is safe and effective in patients with NPC. Specific CTLs responses to LMP2 play a certain role in controlling and preventing the recurrence and metastasis of NPC, which warrants further clinical testing.

External Quality Analysis of Quality Indicators on Specimen Acceptability / 现代检验医学杂志

Objective To analyze the status of quality indicators(QI) on specimen acceptability and establish preliminary qual ity specification.Methods Web based External Quality Assessment system was used to collect data of laboratories partici pated in "Medical quality control indicators in clinical laboratory" from 2015 to 2017,including once in 2015 and 2017 and twice in 2016.Rate and sigma scales were used to evaluate incorrect sample type,incorrect sample container,incorrect fill level and anticoagulant sample clotted.The 25th percentile (P25) and 75th percentile (P75) of the distribution of each QI were employed to establish the high,medium and low specification.Results 5 346,7 593,5 950 and 6 874 laboratories sub mitted the survey results respectively.The P50 of biochemistry (except incorrect fill level),immunology and microbiology reach to 6σ.The P50 of clinical laboratory is 4 to 6σ except for incorrect sample container.There is no significant change of the continuous survey results.Based on results in 2017 to establish the quality specification,the P25 and P75 of the four QIs is 0 and 0.084 4 ％,0 and 0.047 6 ％,0 and 0.114 2 ％,0 and 0.078 4 ％,respectively.Conclusion According to the results of the survey,most laboratories had a faire performance in biochemistry,immunology and microbiology,and clinical laboratory needs to be strengthened.Laboratories should strengthen the laboratory information system construction to ensure the actual and reliable data collection,and make a long time monitoring to achieve a better quality.

The environment, not space, dominantly structures the landscape patterns of the richness and composition of the tropical understory vegetation.

The mechanisms driving the spatial patterns of species richness and composition are essential to the understanding of biodiversity. Numerous studies separately identify the contributions of the environment (niche process) and space (neutral process) to the species richness or composition at different scales, but few studies have investigated the contributions of both types of processes in the two types of data at the landscape scale. In this study, we partitioned the spatial variations in all, exotic and native understory plant species richness and composition constrained by environmental variables and space in 134 plots that were spread across 10 counties in Hainan Island in southern China. The 134 plots included 70 rubber (Hevea brasiliensis) plantation plots, 50 eucalyptus (Eucalyptus urophylla) plantation plots, and 14 secondary forest plots. RDA based variation partitioning was run to assess the contribution of environment and space to species richness and composition. The results showed that the environmental variables alone explained a large proportion of the variations in both the species richness and composition of all, native, and exotic species. The RDA results indicated that overstory composition (forest type here) plays a leading role in determining species richness and composition patterns. The alpha and beta diversities of the secondary forest plots were markedly higher than that of the two plantations. In conclusion, niche differentiation processes are the principal mechanisms that shape the alpha and beta diversities of understory plant species in Hainan Island.

Correlation research between cancer stem cells and the pathological grades of neuroepithelial tumors / 中南大学学报(医学版)

OBJECTIVE@#To explore the methods of isolation, culture and identification of brain tumor stem cells (BTSCs) in neuroepithelial tumor tissues in vitro, and to study the correlation between BTSCs and the patholorical grades of neuroepithelial tumors.@*METHODS@#Tumor cells from patients undergoing neuroepithelial tumors excision were acutely dissociated, triturated into single cells, and then seeded into serum-free medium. After the primary brain tumor spheres (BTSs) were generated, they were triturated again and passaged in fresh medium. The expression of Nestin and CD133 of BTSs was detected by immunocytochemistry staining, and the expression of CD133 of tumor specimen sections was detected by immunohistochemistry staining . The expression of CD133 of 46 brain tumors and 5 normal brain tissues were analysed by SABC immunohistochemical staining, and the correlation between the expression and pathological grade of the tumors was analysed.@*RESULTS@#BTSCs from neuroepithelial tumors could be isolated and cultured, and could be generated and passaged in vitro. The expression of Nestin and CD133 could be detected in BTSCs. CD133 could be detected in neuroepithelial tumor tissues, but not in normal brain tissues. There was significant difference between the expression of CD133 and the different grades of tumors (P < 0.01), and there was a positive correlation between the expression of CD133 and the histologic grading of tumors (P < 0.01).@*CONCLUSION@#A small proportion of stem cells have the ability to self-renew in human neuroepithelial tumors, and there is a positive correlation between the expression of CD133 and histologic grading of tumors.

Preparation,purification and biological function of fusion protein of ovalbumin and HSP70-1ike protein 1 / 中国肿瘤生物治疗杂志

Objective:To prepare,purify the recombinant proteins of HSP70-like protein 1 (HSPTOL1) with a large fragment of chicken ovalbumin (OVA),and to investigate the bio-function of the fusion protein,providing a basis for fur- ther study of the effect and the mechanism of HSPTOL1 as an adjuvant.Methods:The vector containing HSP70L1 cDNA and large fragment of OVA was constructed.The expression of OVA-HSP70L1 fusion protein was induced and the products were purified from inclusion bodies by His-Trap metal chelation chromatography and DEAE ion-exchange chromatography. The bio-activity of the fusion protein was examined by detecting its ability to activate dendritic ceils and to promote the se- cretion of cytokines.Results:The vector was successfully constructed and the molecular weight of the fused OVA- HSPTOL1 protein (with a purity of over 95%) was 68 000.The fusion protein effectively promoted the maturation of den- dritic cells and the production of cytokines such as interleukin-12 and tumor necrosis factor-?.Conclusion:HSPTOL1 may be an effective adjuvant in the fusion protein and it may also promote antigen specific Thl type i mmol/Luno-respon- ses.