Vaccination is the most effective way to prevent coronavirus disease 2019(COVID-19).Vaccine development approaches consist of viral vector vaccines,DNA vaccine,RNA vaccine,live attenuated virus,and recombinant protein...Vaccination is the most effective way to prevent coronavirus disease 2019(COVID-19).Vaccine development approaches consist of viral vector vaccines,DNA vaccine,RNA vaccine,live attenuated virus,and recombinant proteins,which elicit a specific immune response.The use of nanoparticles displaying antigen is one of the alternative approaches to conventional vaccines.This is due to the fact that nano-based vaccines are stable,able to target,form images,and offer an opportunity to enhance the immune responses.The diameters of ultrafine nanoparticles are in the range of 1–100 nm.The application of nanotechnology on vaccine design provides precise fabrication of nanomaterials with desirable properties and ability to eliminate undesirable features.To be successful,nanomaterials must be uptaken into the cell,especially into the target and able to modulate cellular functions at the subcellular levels.The advantages of nano-based vaccines are the ability to protect a cargo such as RNA,DNA,protein,or synthesis substance and have enhanced stability in a broad range of pH,ambient temperatures,and humidity for long-term storage.Moreover,nano-based vaccines can be engineered to overcome biological barriers such as nonspecific distribution in order to elicit functions in antigen presenting cells.In this review,we will summarize on the developing COVID-19 vaccine strategies and how the nanotechnology can enhance antigen presentation and strong immunogenicity using advanced technology in nanocarrier to deliver antigens.The discussion about their safe,effective,and affordable vaccines to immunize against COVID-19 will be highlighted.展开更多
Objective: Kaempferide and 4,2'-dihydroxy-4',5',6'-trimethoxychalcone (DTMC) are two major flavonoids found in Chromolaena odoraia Linn, leaf extract. The aim of this study was to elucidate the mechani...Objective: Kaempferide and 4,2'-dihydroxy-4',5',6'-trimethoxychalcone (DTMC) are two major flavonoids found in Chromolaena odoraia Linn, leaf extract. The aim of this study was to elucidate the mechanism by which these two flavonoids exerted their effect on adipogenesis. The inhibitory effect of kaempferide and DTMC on adipocyte differentiation and their mechanisms involving mitotic clonal expansion (MCE) and apoptosis during the early stage of adipogenesis were investigated. Methods: Confluent 3T3-L1 preadipocytes were induced to differentiate and exposed to the flavonoids during various phases of difTerentiaiion. Intracellular lipid accumulation, cell density and expression of the transcription factors peroxisome proliferator-activated receptor γ and CCAAT/enhancer-binding pro-teins a were assessed using AdipoRed, Oil red 0 and Western blot assays. Effects of both flavonoids on cell proliferation and apoptosis were also determined by carboxyfluorescein diacetate succinimidyl ester and annexin V-fluorescein isothiocyanate/propidium iodide-staining assays, respectively. Results: Kaempferide and DTMC showed significant, concentration-dependent anti-adipogenic activity and effect on cell density in the early phase of adipogenesis. The expression of the transcription factors seemed to be reduced when the treatment was prolonged or in the early phase of adipogenesis. These flavonoids interrupted MCE via inhibition of preadipocyte proliferation and induction of apoptosis. DTMC was nearly three times more potent than kaempferide in inducing apoptosis. Conclusion: Kaempferide and DTMC exerted their anti-adipogenic activity through inhibition of MCE, either by suppressing cell proliferation or by inducing apoptosis during the early phase of differentiation.展开更多
基金OCSC Royal Thai Government-UCAS Scholarship under research collaboration between National Nanotechnology Center(NANOTEC),Thailand,and National Center for Nanoscience and Technology,China(No.P1852764)This work was also supported by the National Natural Science Foundation of China(NSFC)key projects(Nos.31630027 and 32030060)+4 种基金NSFC international collaboration key project(No.51861135103)NSFC-German Research Foundation(DFG)project(No.31761133013)The authors also appreciate the support by“the Beijing-Tianjin-Hebei Basic Research Cooperation Project”(No.19JCZDJC64100)National Key Research&Development Program of China(No.2018YFE0117800)The authors are grateful for Prof.Dr.S.Seraphin at the Professional Authorship Center,Thailand National Science,and Technology Development Agency(NSTDA)for fruitful discussions on the manuscript preparation.
文摘Vaccination is the most effective way to prevent coronavirus disease 2019(COVID-19).Vaccine development approaches consist of viral vector vaccines,DNA vaccine,RNA vaccine,live attenuated virus,and recombinant proteins,which elicit a specific immune response.The use of nanoparticles displaying antigen is one of the alternative approaches to conventional vaccines.This is due to the fact that nano-based vaccines are stable,able to target,form images,and offer an opportunity to enhance the immune responses.The diameters of ultrafine nanoparticles are in the range of 1–100 nm.The application of nanotechnology on vaccine design provides precise fabrication of nanomaterials with desirable properties and ability to eliminate undesirable features.To be successful,nanomaterials must be uptaken into the cell,especially into the target and able to modulate cellular functions at the subcellular levels.The advantages of nano-based vaccines are the ability to protect a cargo such as RNA,DNA,protein,or synthesis substance and have enhanced stability in a broad range of pH,ambient temperatures,and humidity for long-term storage.Moreover,nano-based vaccines can be engineered to overcome biological barriers such as nonspecific distribution in order to elicit functions in antigen presenting cells.In this review,we will summarize on the developing COVID-19 vaccine strategies and how the nanotechnology can enhance antigen presentation and strong immunogenicity using advanced technology in nanocarrier to deliver antigens.The discussion about their safe,effective,and affordable vaccines to immunize against COVID-19 will be highlighted.
基金supported by a grant from Thailand Graduate Institute of Science and Technology (TGIST) (grant number 01–54–007)National Nanotechnology Center at National Science and Technology Development Agency, Thailand
文摘Objective: Kaempferide and 4,2'-dihydroxy-4',5',6'-trimethoxychalcone (DTMC) are two major flavonoids found in Chromolaena odoraia Linn, leaf extract. The aim of this study was to elucidate the mechanism by which these two flavonoids exerted their effect on adipogenesis. The inhibitory effect of kaempferide and DTMC on adipocyte differentiation and their mechanisms involving mitotic clonal expansion (MCE) and apoptosis during the early stage of adipogenesis were investigated. Methods: Confluent 3T3-L1 preadipocytes were induced to differentiate and exposed to the flavonoids during various phases of difTerentiaiion. Intracellular lipid accumulation, cell density and expression of the transcription factors peroxisome proliferator-activated receptor γ and CCAAT/enhancer-binding pro-teins a were assessed using AdipoRed, Oil red 0 and Western blot assays. Effects of both flavonoids on cell proliferation and apoptosis were also determined by carboxyfluorescein diacetate succinimidyl ester and annexin V-fluorescein isothiocyanate/propidium iodide-staining assays, respectively. Results: Kaempferide and DTMC showed significant, concentration-dependent anti-adipogenic activity and effect on cell density in the early phase of adipogenesis. The expression of the transcription factors seemed to be reduced when the treatment was prolonged or in the early phase of adipogenesis. These flavonoids interrupted MCE via inhibition of preadipocyte proliferation and induction of apoptosis. DTMC was nearly three times more potent than kaempferide in inducing apoptosis. Conclusion: Kaempferide and DTMC exerted their anti-adipogenic activity through inhibition of MCE, either by suppressing cell proliferation or by inducing apoptosis during the early phase of differentiation.