A survey of jellyfish sting knowledge among Thai divers in Thailand

Background: In tropical regions, jellyfish envenomation is a persistent hazard for people who spend time in the sea. Jellyfish stings can be dangerous, and among the people who face the greatest risk are scuba divers. This study therefore sought to determine the level of knowledge divers in Thailand have about the threat of jellyfish envenomation.  Materials and methods: In April 2018, a total of 238 divers responded to a questionnaire, thereby providing data for further statistical analysis. Results: The findings revealed that 31.91% of the study participants cited jellyfish stings as their most frequently encountered injury, with 68.09% having personal experience of the problem, or having seen others injured by jellyfish. However, 34.03% of the sample respondents believed their own level of knowledge to be “low” or “none”. The mean score was 71%, which can be considered satisfactory, but the scores for items concerning the recognition of signs of envenomation and items about first aid responses (52.74% and 59.13%, respectively) were not acceptable.  Conclusions: Divers frequently experience jellyfish stings, and diving personnel were highly rated for their knowledge in this area. However, very few were fully confident in their first aid capabilities, and therefore it can be argued that it is necessary to improve the level of medical education and to provide training to eliminate this weakness.

Liposome and polymer-based nanomaterials for vaccine applications

Nanoparticles (NPs) are effective and safe adjuvants for antigen delivery in modern vaccinology. Biodegradable nanomaterials with suitable properties are frequently applied for conjugation or loading with antigens; they protect the antigens from degradation in vivo. NPs are applied as effective delivery system to facilitate antigen uptake by antigen presenting cells (APCs) and especially dendritic cells (DCs) both in vitro and in vivo. Using nanoparticles to target DCs is an effective method to deliver antigens and potent immunomodulators. Uptake of NPs by DCs enhances the intracellular process of antigens and the antigen presentation pathway by MHC class I and II molecules to induce both CD4+ and CD8+ T-cell responses. Liposome and polymer-based NPs are now extensively applied as effective adjuvants or immunomodulators in several types of vaccines. In this review, the nanomaterials for vaccine application are focused intensively in poly(lactic-co-glycolic) acid (PLGA), dendrimers, liposomes, nanogels and micelles which are the targeted antigen delivery system, and present high potential as a promising future strategy for DNA-based, bacterial and viral vaccines. Further advances in nanotechnology and molecular immunology techniques will enhance the success of targeting and lead to the next generation of nano-delivery systems

Hepatitis C virus E2 protein encapsulation into poly D, L-lactic-co-glycolide microspheres could induce mice cytotoxic T-cell response

Piyachat Roopngam,1,2 Kewei Liu,1,2 Lin Mei,2 Yi Zheng,2 Xianbing Zhu,1,2 Hsiang-I Tsai,1,2 Laiqiang Huang1,2 1School of Life Sciences, Tsinghua University, Beijing, People’s Republic of China; 2The Shenzhen Key Laboratory of Gene and Antibody Therapy, Center for Biotechnology and Biomedicine, State Key Laboratory of Health Sciences and Technology, Division of Life and Health Sciences, Graduate School at Shenzhen, Tsinghua University, Shenzhen, People’s Republic of China Abstract: Hepatitis C virus (HCV) is known to cause hepatitis and hepatocellular carcinoma. E2 envelope glycoprotein of HCV type (HCV-E2) has been reported to bind human host cells and is a major target for developing anti-HCV vaccines. However, the therapeutic vaccine for infected patients still needs further development. The vaccine aims to provide cytotoxic T-cells to eliminate infected cells and hepatocellular carcinoma. Currently, there is no effective HCV therapeutic vaccine because most chronically infected patients rarely generate cytotoxic T-cells, even though they have high levels of neutralizing antibodies. Therefore, the adjuvant must be applied to enhance the efficacy of the therapeutic vaccine. In this study, we constructed HCV1b-E2 recombinant protein, a truncated form of peptide, to combine with an effective vaccine adjuvant and delivery system by using poly D, L-lactic-co-glycolide (PLGA) microspheres. HCV1b-E2 protein was effectively encapsulated into PLGA microspheres (HCV1b-E2-PLGA) as a strategy to deliver an insoluble form of HCV1b-E2 protein. The size and shape of PLGA microspheres were generated properly to carry an insoluble form of viral peptide in vivo. The encapsulated viral protein was slowly and continuously released from PLGA microspheres, which indicated the property of the adjuvant. HCV1b-E2-PLGA can trigger a cell-mediated immune response by inducing an expression of mice CD8+ T-cells. Our results demonstrated that HCV1b-E2-PLGA-immunized mice have a significantly increased CD8+ T-cell number, whereas HCV1b-E2-immunized mice have a lower number of CD8+ T-cells. Moreover, HCV1b-E2-PLGA could induce a specific antibody to viral protein, and the immune cells could secrete IFN-γ, which is a significant cytokine for viral response. Thus, HCV1b-E2-PLGA is shown to have adjuvant property and efficacy in the murine model, which is a good strategy to develop HCV prophylactic and therapeutic vaccines. Keywords: hepatitis C virus, HCV, therapeutic vaccine, PLGA microspheres, HCV-E2 peptide, cytotoxic T-cells, hepatitis, hepatocellular carcinom