A Bacillus-based Coxsackie virus A16 mucosal vaccine induces strong neutralizing antibody responses.

The purpose of this study was to construct a Coxsackie virus A16 (CA16) mucosal vaccine and evaluate its ability to induce immune response. VP1 gene of CA16 was inserted into the genome of Bacillus subtilis via recombination and displayed on the surface of the spores. This Bacillus-based vaccine was used for intranasal immunization of mice and the serum antibody titer was determined by enzyme-linked immunosorbent assay (ELISA). Neutralization activity of the serum from immunized mice was analyzed by an in vitro neutralizing test. VP1 gene was successfully integrated into the genome of Bacillus subtilis and was expressed on the surface of Bacillus spores. Intranasal immunization of mice with this vaccine induced a higher level of VP1 specific IgA and IgG than in mice of the control group (p < 0.05). The neutralizing antibody titer in the spore immunization group was 1 : 169, which was higher than that in the control group (p < 0.05). We concluded that vaccine prepared by displaying CA16 VP1 protein on the surface of Bacillus subtilis spores can stimulate mice to produce protective neutralizing antibodies, which provides foundations for the development of CA16 mucosal vaccine.

Antiviral activity of polysaccharide extract from Laminaria japonica against respiratory syncytial virus.

This study was designed to investigate the inhibition activity of polysaccharide extract from Laminaria japonica against RSV. The polysaccharide from Laminaria japonica was isolated by ethanol precipitation. HEK293 cells were infected with RVS, and the antiviral activity of polysaccharide extract against RSV in host cells was tested. By using ELISA and western blot assay, the expression level of IFN-α and IRF3 and their functional roles in polysaccharide-mediated antiviral activity against RSV were investigated. The polysaccharide extract from Laminaria japonica had low toxicity to HEK293 cell. The TC50 to HEK293 cells was up to 1.76mg/mL. Furthermore, the EC50 of polysaccharide extract to RSV was 5.27µg/mL, and TI was 334. The polysaccharide extract improved IRF-3 expression which promoted the level of IFN-α. IN CONCLUSION: Polysaccharide extract from Laminaria japonica elicits antiviral activity against RSV by up-regulation of IRF3 signaling-mediated IFN-α production.

Lgr5 regulates the regeneration of lesioned nasal respiratory epithelium.

Nasal respiratory epithelium is a ciliated pseudostratified columnar epithelium. The cellular components of nasal respiratory epithelium include ciliated cells, goblet cells, and basal cells. Until now, our knowledge in the development of nasal respiratory epithelium is still limited and the cellular mechanism of regeneration is still elusive. In this study, we found that adult stem cell marker leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5) is expressed in the mice nasal respiratory epithelium. Both immunostaining and lineage tracing analysis indicated Lgr5 positive cells in the nasal respiratory epithelium are proliferative stem/progenitor cells. Using the Rosa-Tdtomato and Rosa26-DTR mice, we elucidated that Lgr5+ cells participate in the regeneration of lesioned nasal respiratory epithelium, and this group of cells is necessary in the process of epithelium recovery. Using the in vitro culture system, we observed the formation of spheres from Lgr5+ cells and these spheres have the capacity to generate other types of cells. Above all, this study reported a group of previously unidentified progenitor/stem cells in nasal respiratory epithelium, unveiling the potential cellular mechanism in nasal respiratory epithelium regeneration.

Synthesis of Pyrazine-1,3-thiazine Hybrid Analogues as Antiviral Agent Against HIV-1, Influenza A (H1N1), Enterovirus 71 (EV71), and Coxsackievirus B3 (CVB3).

A novel series of pyrazine-1,3-thiazine hybrid conjugates were synthesized in excellent yield. These derivatives were subsequently tested against human immunodeficiency virus (HIV-1); hemagglutinin type 1 and neuraminidase type 1-'influenza' A (H1N1) virus; enterovirus 71 (EV71); and coxsackievirus B3. The effect of these conjugates on the key enzymes responsible for the progression of these viral infections was also illustrated via enzyme-based assay, such as HIV-1 reverse transcriptase (RT) and neuraminidase, where entire tested molecules showed considerable inhibition. Particularly, among the tested derivatives, compound 3k was identified as most promising inhibitor of HIV-1 with 94% of inhibition (IC50 3.26 ± 0.2 µm). Moreover, the compound 3d was found to be the most potent analogue to inhibit the H1N1 virus with IC50 of 5.32 ± 0.4 µm together with inhibition of the neuraminidase enzyme (IC50 11.24 ± 1.1 µm). In regard to inhibitory activity against enterovirus 71 (EV71) and coxsackievirus B3 (CVB3), the tested derivatives showed considerable inhibition of infection. Molecular docking studies were also performed for the most promising inhibitors with their corresponding target protein to exemplify the structural requirement for better inhibitory activity. The results of inhibitory assay showed that designed molecules possess considerable inhibitory activity against the virus tested.

3-Bromopyruvate inhibits cell proliferation and induces apoptosis in CD133+ population in human glioma.

The study was aimed to investigate the role of 3-bromopyruvate in inhibition of CD133+ U87 human glioma cell population growth. The results demonstrated that 3-bromopyruvate inhibited the viability of both CD133+ and parental cells derived from U87 human glioma cell line. However, the 3-bromopyruvate-induced inhibition in viability was more prominent in CD133+ cells at 10 µM concentration after 48 h. Treatment of CD133+ cells with 3-bromopyruvate caused reduction in cell population and cell size, membrane bubbling, and degradation of cell membranes. Hoechst 33258 staining showed condensation of chromatin material and fragmentation of DNA in treated CD133+ cells after 48 h. 3-Bromopyruvate inhibited the migration rate of CD133+ cells significantly compared to the parental cells. Flow cytometry revealed that exposure of CD133+ cells to 3-bromopyruvate increased the cell population in S phase from 24.5 to 37.9 % with increase in time from 12 to 48 h. In addition, 3-bromopyruvate significantly enhanced the expression of Bax and cleaved caspase 3 in CD133+ cells compared to the parental cells. Therefore, 3-bromopyruvate is a potent chemotherapeutic agent for the treatment of glioma by targeting stem cells selectively.

Effects of survivin interference RNA on non-small cell lung carcinoma.

OBJECTIVES: The primary purpose of this study was to investigate the in vitro and in vivo effect of survivin interference RNA (siRNA) on non-small cell lung cancer. METHODS: Lentivirus was used as a vector to transfer siRNA into human lung cancer A549 cells. The proliferation of the cancer cells was assessed by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The lentivirus-mediated siRNA was also injected into the transplanted A549 tumor tissues in mice. Tumour growth was assessed after 11 injections over a period of 21 days. RESULTS: Compared with the placebo and the blank lentiviral vector groups, the siRNA treatment group had reduced cell growth rate following 4 days of the treatment (P < 0.01). The average size of the transplanted A549 tumours in the siRNA treatment group (0.75+/-0.16 cm3, n=8) was smaller than in the placebo (2.09+/-0.22 cm3, n=6) or the blank lentivrial vector groups (1.89+/-0.18 cm3, n=6) (P < 0.01). The tumour growth inhibition rate in the siRNA groups was 46.1%. CONCLUSION: Lentivirus-mediated siRNA therapy inhibits the growth of human lung cancer cells in vitro. The siRNA therapy also suppresses the growth of the transplanted lung cancer in mice.