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The major challenge in COVID-19 vaccine effectiveness is immune escape by SARS-CoV-2 variants. To overcome this, an Omicron-specific messenger RNA (mRNA) vaccine was designed. The extracellular domain of the spike of the Omicron variant was fused with a modified GCN4 trimerization domain with low immunogenicity (TSomi). After immunization with TSomi mRNA in hamsters, animals were challenged with SARS-CoV-2 virus. The raised nonneutralizing antibodies or cytokine secretion responses can recognize both Wuhan S and Omicron S. However, the raised antibodies neutralized SARS-CoV-2 Omicron virus infection but failed to generate Wuhan virus neutralizing antibodies. Surprisingly, TSomi mRNA immunization protected animals from Wuhan virus challenge. These data indicated that non-neutralizing antibodies or cellular immunity may play a more important role in vaccine-induced protection than previously believed. Next-generation COVID-19 vaccines using the Omicron S antigen may provide sufficient protection against ancestral or current SARS-CoV-2 variants.
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Antígenos de Grupos Sanguíneos , COVID-19 , Animais , Cricetinae , Humanos , SARS-CoV-2/genética , Vacinas contra COVID-19 , Anticorpos Neutralizantes , COVID-19/prevenção & controle , RNA Mensageiro/genética , Vacinas de mRNA , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus/genéticaRESUMO
Aluminum-containing salts are commonly used as antacids and vaccine adjuvants; however, key features of functional activities remain unclear. Here, we characterized vaccine formulations based on aluminum phosphate and aluminum hydroxide and investigated the respective modes of action linking physicochemical properties and catalytic ability. TEM microscopy indicated that aluminum phosphate gel solutions are amorphous, whereas aluminum hydroxide gel solutions have a crystalline structure consistent with boehmite. At very low BSA concentrations, 100 % adsorption of the protein on aluminum hydroxide could be achieved. As the protein concentration increased, the amount of adsorbed BSA decreased as fewer vacant sites were available on the surface of the adjuvants. Notably, less than 20 % adsorption was observed in aluminum phosphate. The protein adsorption profiles should confront the requirements for vaccine immunoavailability. In terms of catalytic ability, the prepared aluminum salts were tested for their ability to drive the amphiphilic engineering of oligo(lactic acid) (OLA) onto methoxy poly(ethylene glycol). It was concluded that aluminum hydroxide, rather than aluminum phosphate, is suitable to be a vaccine adjuvant according to the morphology and antigen adsorption efficiency results; on the other hand, aluminum phosphate may be a more efficient catalyst for the synthesis of polymeric emulsifiers than aluminum hydroxide. The results provide critical mechanistic insight into aluminum-containing salts in vaccine formulations.
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Emulsion-based adjuvants have been demonstrated to be an effective tool in increasing vaccine efficacy. Here, we aimed to launch a mechanistic study on how emulsion adjuvants interact with immune cells and to elucidate the roles of the core oil in vaccine immunogenicity. Our results showed that treatment of dendritic cells (DCs) and splenocytes with a squalene-based emulsion (referred as SqE) induced reactive oxidative species (ROS) production and resulted in an increase in apoptotic and necrotic cells in a concentration- and time-dependent manner. Furthermore, DCs cocultured with cellular debris of SqE-pretreated splenocytes resulted in a higher level of ovalbumin (OVA) antigen uptake by DCs than those cocultured with untreated splenocytes. Interestingly, the potency was rather attenuated when splenocytes were pretreated with N-acetyl-cysteine, an antioxidant. Notably, SqE possesses a high impact on eliciting ROS-mediated antigen uptake compared with a squalane-based emulsion (SqA). Concordantly, immunogenicity studies have shown that SqE is better able than SqA to activate antigen-presenting cells, and to enhance antigen-specific T-cell immunity. Taken together, our results show that unsaturated squalene oil cored within emulsions plays a crucial role in ROS-mediated antigen uptake and cellular immunity, providing a basis for the design and development of vaccine adjuvant.
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Adjuvantes Imunológicos/farmacologia , Imunidade Celular/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Esqualeno/farmacologia , Vacinas/imunologia , Adjuvantes Imunológicos/química , Animais , Antígenos/imunologia , Antígenos/metabolismo , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Desenho de Fármacos , Emulsões , Feminino , Imunogenicidade da Vacina , Camundongos , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Espécies Reativas de Oxigênio/imunologia , Esqualeno/química , Vacinas/administração & dosagem , Vacinas/químicaRESUMO
Cancer vaccines are considered to be a promising tool for cancer immunotherapy. However, a well-designed cancer vaccine should combine a tumor-associated antigen (TAA) with the most effective immunomodulatory agents and/or delivery system to provoke intense immune responses against the TAA. In the present study, we introduced a new approach by conjugating the immunomodulatory molecule LD-indolicidin to the hydrophilic chain end of the polymeric emulsifier poly(ethylene glycol)-polylactide (PEG-PLA), allowing the molecule to be located close to the surface of the resulting emulsion. A peptide/polymer conjugate, named LD-indolicidin-PEG-PLA, was synthesized by conjugation of the amine end-group of LD-indolicidin to the N-hydroxysuccinimide-activated carboxyl end-group of PEG. As an adjuvant for cancer immunotherapeutic use, TAA vaccine candidate formulated with the LD-indolicidin-PEG-PLA-stabilized squalene-in-water emulsion could effectively help to elicit a T helper (Th)1-dominant antigen-specific immune response as well as antitumor ability, using ovalbumin (OVA) protein/EG7 cells as a TAA/tumor cell model. Taken together, these results open up a new approach to the development of immunomodulatory antigen delivery systems for vaccine adjuvants and cancer immunotherapy technologies.
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Antígenos de Neoplasias/imunologia , Sistemas de Liberação de Medicamentos , Imunidade/efeitos dos fármacos , Neoplasias/imunologia , Peptídeos/química , Polietilenoglicóis/química , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Animais , Antígenos de Neoplasias/química , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Vacinas Anticâncer/química , Vacinas Anticâncer/imunologia , Emulsões , Feminino , Imunomodulação , Imunoterapia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/tratamento farmacológico , Ovalbumina/química , Esqualeno/química , Succinimidas/químicaRESUMO
Successful DNA vaccination generally requires the aid of either a viral vector within vaccine components or an electroporation device into the muscle or skin of the host. However, these systems come with certain obstacles, including limited transgene capacity, broad preexisting immunity in humans, and substantial cell death caused by high voltage pulses, respectively. In this study, we repurposed the use of an amphiphilic bioresorbable copolymer (ABC), called PLA-PEG, as a surface engineering agent that conciliates lipid nanoparticles (LNPs) between stability during preparation and biocompatibility post-vaccination. The LNP carrier can be loaded with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike-specific DNA; in this form, the DNA-LNP is immunogenic in hamsters and elicits protective immunity following DNA-LNP vaccination against heterologous virus challenge or as a hybrid-type vaccine booster against SARS-CoV-2 variants. The data provide comprehensive information on the relationships between LNP composition, manufacturing process, and vaccine efficacy. The outcomes of this study offer new insights into designing next-generation LNP formulations and pave the way for boosting vaccine power to combat existing and possible emerging infectious diseases/pathogens.
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High performance of Ga-doped ZnO (GZO) prepared using metalorganic chemical vapor deposition (MOCVD) was employed in GaN blue light-emitting diodes (LEDs) as transparent conductive layers (TCL). By the post-annealing process, the annealed 800°C GZO films exhibited a high transparency above 97% at wavelength of 450 nm. The contact resistance of GZO decreased with the annealing temperature increasing. It was attributed to the improvement of the GZO crystal quality, leading to an increase in electron concentration. It was also found that some Zn atom caused from the decomposition process diffused into the p-GaN surface of LED, which generated a stronger tunneling effect at the GZO/p-GaN interface and promoted the formation of ohmic contact. Moreover, contrast to the ITO-LED, a high light extraction efficiency of 77% was achieved in the GZO-LED at injection current of 20 mA. At 350 mA injection current, the output power of 256.51 mW of GZO-LEDs, corresponding to a 21.5% enhancement as compared to ITO-LEDs was obtained; results are promising for the development of GZO using the MOCVD technique for GaN LED applications.
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Gálio/química , Iluminação/instrumentação , Semicondutores , Óxido de Zinco/química , Desenho de Equipamento , Análise de Falha de EquipamentoRESUMO
Nasal spray vaccination is viewed as a promising strategy for inducing both mucosal and systemic protection against respiratory SARS-CoV-2 coronavirus. Toward this goal, a safe and efficacious mucosal adjuvant is necessary for the transportation of the antigen across the mucosal membrane and antigen recognition by the mucosal immune system to generate broad-spectrum immune responses. This study describes the immunological aspects of SARS-CoV-2 spike (S)-protein after being formulated with CpG oligodeoxynucleotides (ODNs) and squalene nanoparticles (termed PELC). Following intranasal delivery in mice, higher expression levels of major histocompatibility complex (MHC) class II and costimulatory molecules CD40 and CD86 on CD11c+ cells were observed at the draining superficial cervical lymph nodes in the CpG-formulated S protein group compared with those vaccinated with S protein alone. Subsequently, the activated antigen-presenting cells downstream modulated the cytokine secretion profiles and expanded the cytotoxic T lymphocyte activity of S protein-restimulated splenocytes. Interestingly, the presence of PELC synergistically enhanced cell-mediated immunity and diminished individual differences in S protein-specific immunogenicity. Regarding humoral responses, the mice vaccinated with the PELC:CpG-formulated S protein promoted the production of S protein-specific IgG in serum samples and IgA in nasal and bronchoalveolar lavage fluids. These results indicate that PELC:CpG is a potential mucosal adjuvant that promotes mucosal/systemic immune responses and cell-mediated immunity, a feature that has implications for the development of a nasal spray vaccine against COVID-19.
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We fabricated a gas sensor with a wide-bandgap ZnGa2O4 (ZGO) epilayer grown on a sapphire substrate by metalorganic chemical vapor deposition. The ZGO presented (111), (222) and (333) phases demonstrated by an X-ray diffraction system. The related material characteristics were also measured by scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. This ZGO gas sensor was used to detect nitric oxide (NO) in the parts-per-billion range. In this study, the structure effect on the response of the NO gas sensor was studied by altering the sensor dimensions. Two approaches were adopted to prove the dimension effect on the sensing mechanism. In the first approach, the sensing area of the sensors was kept constant while both channel length (L) and width (W) were varied with designed dimensions (L × W) of 60 × 200, 80 × 150, and 120 ×100 µm2. In the second, the dimensions of the sensing area were altered (60, 40, and 20 µm) with W kept constant. The performance of the sensors was studied with varying gas concentrations in the range of 500 ppb~10 ppm. The sensor with dimensions of 20 × 200 µm2 exhibited a high response of 11.647 in 10 ppm, and 1.05 in 10 ppb for NO gas. The sensor with a longer width and shorter channel length exhibited the best response. The sensing mechanism was provided to explain the above phenomena. Furthermore, the reaction between NO and the sensor surface was simulated by O exposure of the ZGO surface in air and calculated by first principles.
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Integrative medicine comprising a tumor-associated antigen vaccine and chemotherapeutic regimens has provided new insights into cancer therapy. In this study, the AB-type diblock copolymers poly(ethylene glycol)-polylactide (PEG-PLA) were subjected to the dispersion of poorly water-soluble molecules in aqueous solutions. The physicochemical behavior of the chemotherapeutic agent DBPR114 in the PEG-PLA-polymeric aqueous solution was investigated by dynamic light scattering (DLS) technology. In vitro cell culture indicated that replacing the organic solvent DMSO with PEG-PLA polymeric micelles could maintain the anti-proliferative effect of DBPR114 on leukemia cell lines. A murine tumor-associated antigen vaccine model was established in tumor-bearing mice to determine the effectiveness of these formulas in inducing tumor regression. The results demonstrated that the therapeutic treatments effectively reinforced each other via co-delivery of antitumor drug/antigen agents to synergistically integrate the efficacy of cancer therapy. Our findings support the potential use of polymeric micellar systems for aqueous solubilization and expansion of antitumor activity intrinsic to DBPR114 and tumor-associated antigen therapy.
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This study describes the assessment of mucosal adjuvant activity of a squalene-based nanoemulsion (SQ@NE) following intravaginal delivery in mice. After immunization, a high level of recruitment of CD11b/c+ granulocytes and F4/80+ macrophages was observed in the vaginal mucosal tissues of the mice immunized with a model protein ovalbumin (OVA) formulated with SQ@NE, and then downstream regulated the expression of MHC II and costimulatory molecules CD40 and CD86 on CD11c+ cells harvested from the associated draining lymph node. With respect to cytotoxic T lymphocyte immunity, the mice immunized with SQ@NE-formulated OVA elicited a high population of OVA-specific CD8+ cells in the spleen and increased the secretion of IFN-γ, IL-2 and IL-17 from OVA-restimulated splenocytes compared with those immunized with OVA alone. By studying in vivo fluorescence imaging and B-cell immunoassays, we discovered how SQ@NE prolongs the retention of antigen depots at the mucosal membrane of the immune inductive site and allows them to properly drive the production of antibodies. The data demonstrated that SQ@NE prolonged fluorescence-labeled OVA retention at the genital tract and augmented the production of OVA-specific IgG in sera and IgA in vaginal washes. These results indicate that SQ@NE is a promising vaginal adjuvant for the induction of both mucosal and systemic immune responses, a feature that provides implications for the development of a mucosal vaccine against genital infections and sexually transmitted diseases.
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Mucosa/efeitos dos fármacos , Mucosa/imunologia , Nanopartículas/administração & dosagem , Esqualeno/administração & dosagem , Vagina/efeitos dos fármacos , Vagina/imunologia , Adjuvantes Imunológicos/administração & dosagem , Administração Intravaginal , Animais , Emulsões , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/administração & dosagemRESUMO
Vaccination is regarded as the most effective intervention for controlling the coronavirus disease 2019 (COVID-19) pandemic. The objective of this study is to provide comprehensive information on lipid squalene nanoparticle (SQ@NP)-adjuvanted COVID-19 vaccines regarding modulating immune response and enhancing vaccine efficacy. After being adjuvanted with SQ@NP, the SARS-CoV-2 spike (S) subunit protein was intramuscularly (i.m.) administered to mice. Serum samples investigated by ELISA and virus neutralizing assay showed that a single-dose SQ@NP-adjuvanted S-protein vaccine can induce antigen-specific IgG and protective antibodies comparable with those induced by two doses of nonadjuvanted protein vaccine. When the mice received a boosting vaccine injection, anamnestic response was observed in the groups of adjuvanted vaccine. Furthermore, the secretion of cytokines in splenocytes, such as interferon (IFN)-γ, interleukin (IL)-5 and IL-10, was significantly enhanced after adjuvantation of S-protein vaccine with SQ@NP; however, this was not the case for the vaccine adjuvanted with conventional aluminum mineral salts. Histological examination of injection sites showed that the SQ@NP-adjuvanted vaccine was considerably well tolerated following i.m. injection in mice. These results pave the way for the performance tuning of optimal vaccine formulations against COVID-19.
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COVID-19 , Nanopartículas , Adjuvantes Imunológicos , Animais , Anticorpos Antivirais , Vacinas contra COVID-19 , Humanos , Lipídeos , Camundongos , SARS-CoV-2 , EsqualenoRESUMO
Clinical cases of allergic reaction that are due to excipients containing polyethylene glycol (PEG), a hydrophilic molecule commonly used in drug/vaccine formulations, has attracted much attention in recent years. In order to develop PEG-free adjuvants, we investigated the feasibility of natural ingredients in the human body such as hyaluronic acid in the form of hyaluronic acid-glycine cholesterol (HACH) conjugate as an excipient for vaccine formulation. Interestingly, HACH grafted with ~13 wt.% cholesterol has good water dispersity and can serve as an emulsifier to stabilize the squalene/water interfaces, yielding a milky white and isotropic emulsion (SQ@HACH) after being passed through a high-shear microfluidizer. Our results show that SQ@HACH particles possessed a unimodal average hydrodynamic diameter of approximately 190 nm measured by dynamic light scattering and exhibited good stability upon storage at 4 °C and 37 °C for over 20 weeks. The results of immunogenicity using a mouse model with ovalbumin (OVA) as the antigen revealed that SQ@HACH significantly enhanced antigen-specific immune responses, including the polarization of IgG antibodies, the cytokine secretions of T cells, and enhancement of cytotoxic T lymphocyte (CTL) activation. Moreover, SQ@HACH revealed lower local inflammation and rapidly absorbing properties compared with AlPO4 after intramuscular injection in vivo, indicating the potential functions of the HA-derived conjugate as an excipient in vaccine formulations for enhancement of T cell-mediated immunity.
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BACKGROUND: Emulsion adjuvants are a potent tool for effective vaccination; however, the size matters on mucosal signatures and the mechanism of action following intranasal vaccination remains unclear. Here, we launch a mechanistic study to address how mucosal membrane interacts with nanoemulsion of a well-defined size at cellular level and to elucidate the impact of size on tumor-associated antigen therapy. METHODS: The squalene-based emulsified particles at the submicron/nanoscale could be elaborated by homogenization/extrusion. The mucosal signatures following intranasal delivery in mice were evaluated by combining whole-mouse genome microarray and immunohistochemical analysis. The immunological signatures were tested by assessing their ability to influence the transportation of a model antigen ovalbumin (OVA) across nasal mucosal membranes and drive cellular immunity in vivo. Finally, the cancer immunotherapeutic efficacy is monitored by assessing tumor-associated antigen models consisting of OVA protein and tumor cells expressing OVA epitope. RESULTS: Uniform structures with ~200 nm in size induce the emergence of membranous epithelial cells and natural killer cells in nasal mucosal tissues, facilitate the delivery of protein antigen across the nasal mucosal membrane and drive broad-spectrum antigen-specific T-cell immunity in nasal mucosal tissues as well as in the spleen. Further, intranasal vaccination of the nanoemulsion could assist the antigen to generate potent antigen-specific CD8+ cytotoxic T-lymphocyte response. When combined with immunotherapeutic models, such an effective antigen-specific cytotoxic activity allowed the tumor-bearing mice to reach up to 50% survival 40 days after tumor inoculation; moreover, the optimal formulation significantly attenuated lung metastasis. CONCLUSIONS: In the absence of any immunostimulator, only 0.1% content of squalene-based nanoemulsion could rephrase the mucosal signatures following intranasal vaccination and induce broad-spectrum antigen-specific cellular immunity, thereby improving the efficacy of tumor-associated antigen therapy against in situ and metastatic tumors. These results provide critical mechanistic insights into the adjuvant activity of nanoemulsion and give directions for the design and optimization of mucosal delivery for vaccine and immunotherapy.
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Adjuvantes Imunológicos/uso terapêutico , Administração Intranasal/métodos , Imunomodulação/imunologia , Imunoterapia/métodos , Mucosa/imunologia , Nanopartículas/química , Vacinação/métodos , Adjuvantes Imunológicos/farmacologia , Animais , Feminino , Humanos , CamundongosRESUMO
PURPOSE: To enhance the water affinity of W/O emulsion-adjuvanted vaccines, we used three bioresorbable polymers named PEG-b-PLA, PEG-b-PCL, and PEG-b-PLACL as hydrophilic emulsifier to stabilize the interfaces between the oily Montanide ISA 51 adjuvant and the antigen media. METHODS: Polymers were synthesized by ring-opening polymerization of lactide and/or epsilon-caprolactone in the presence of monomethoxy PEG. (1)H NMR and GPC data showed that obtained polymers consisted of 70 wt.% hydrophilic PEG block and 30 wt.% lipophilic PLA, PCL, PLACL block with molecular weights of 7,000. RESULTS: The polymer-stabilized ISA51 emulsions have high affinity to water, such that the stock of antigen-encapsulating emulsion could be re-dispersed into PBS before injection, thus yielding stable and injectable W/O/W emulsion nanoparticles. Immunogenicity studies showed that PEG-b-PLACL/ISA51/PBS-formulated ovalbumin with only 5% of ISA51 oily adjuvant could induce the same level of antibody titers as those induced by PBS/ISA51-formulated ovalbumin. CONCLUSIONS: The novel multi-phase emulsions increase fluidity and conceptually diminish local reactions with respect to the W/O type vaccines produced from the same oil. These features are of great interest for applications in candidate vaccine delivery, especially for further optimization of alternative immunization routes, such as intramuscular, transdermal or mucosal administration.
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Adjuvantes Imunológicos , Emulsões , Polímeros/química , Animais , Cromatografia em Gel , Ensaio de Imunoadsorção Enzimática , Feminino , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB CRESUMO
The effect of antigen-adjuvant associations on antigen uptake and antigen-specific humoral immunity is studied in detail. After formulation with a squalene-based double emulsion (referred to as PELC), the protein ovalbumin (OVA) was intramuscularly injected in mice, in either a separation (OVA-PELCSE), a surface attachment (OVA-PELCSA) or an encapsulation (OVA-PELCEN) manner. As an antigen delivery system, a significant increase of OVA-loaded cells migrating into draining lymph nodes (LNs) was detected in the PELC-formulated OVA groups, attachment and encapsulation as well. Additionally, OVA-PELCEN allowed the mice to induce a delayed but long-lasting OVA-specific antibodies production compared to OVA-PELCSA. In the extreme case where no antigen-adjuvant association at all (i.e., OVA-PELCSE), we found that even with the presence of PELC at the contralateral limb, an elevated level of OVA uptake was detected in ipsilateral draining CD11c+ LN cells, which subsequently augmented the production of OVA-specific IgG antibodies during early vaccination. The mouse study allows us to find out the optimal vaccine formulation and deepens our understandings on how antigen-adjuvant associations can govern the cellular uptake and transportation of protein antigen into the draining LNs and prolong antigen-specific humoral immunity, even if the antigen and the adjuvant are given separately.
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Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Antígenos/imunologia , Imunidade Humoral , Animais , Células Apresentadoras de Antígenos/metabolismo , Antígeno CD11c/metabolismo , Movimento Celular/efeitos dos fármacos , Emulsões/química , Feminino , Imunidade Humoral/efeitos dos fármacos , Injeções Intramusculares , Linfonodos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , VacinaçãoRESUMO
A gas sensor based on a ZnGa2O4(ZGO) thin film grown by metalorganic chemical vapor deposition operated under the different temperature from 25 °C to 300 °C is investigated in this study. This sensor shows great sensing properties at 300 °C. The sensitivity of this sensor is 22.21 as exposed to 6.25 ppm of NO and its response time is 57 s. Besides that, the sensitivities are 1.18, 1.27, 1.06, and 1.00 when exposed to NO2(500 ppb), SO2 (125 ppm), CO (125 ppm), and CO2 (1500 ppm), respectively. These results imply that the ZGO gas sensor not only has high sensitivity, but also has great selectivity for NO gas. Moreover, the obtained results suggest that ZGO sensors are suitable for the internet of things(IOT) applications.
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A single-crystalline ZnGa2O4 epilayer was successfully grown on c-plane (0001) sapphire substrate by metal-organic chemical vapor deposition. This epilayer was used as a ternary oxide semiconductor for application in high-performance metal-semiconductor-metal photoconductive deep-ultraviolet (DUV) photodetectors (PDs). At a bias of 5 V, the annealed ZnGa2O4 PDs showed better performance with a considerably low dark current of 1 pA, a responsivity of 86.3 A/W, cut-off wavelength of 280 nm, and a high DUV-to-visible discrimination ratio of approximately 107 upon exposure to 230 nm DUV illumination than that of as-grown ZnGa2O4 PDs. The as-grown PDs presented a dark current of 0.5 mA, a responsivity of 2782 A/W at 230 nm, and a photo-to-dark current contrast ratio of approximately one order. The rise time of annealed PDs was 0.5 s, and the relatively quick decay time was 0.7 s. The present results demonstrate that annealing process can reduce the oxygen vacancy defects and be potentially applied in ZnGa2O4 film-based DUV PD devices, which have been rarely reported in previous studies.
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To accomplish an innovative vaccine design, there are two key challenges: developing formulations that avoid cold chain shipment and finding a delivery vehicle that is absorbable in vivo. Here, we explored the design and performance of a colloidal vesicle that enabled us to consider both challenges. We used polymeric bioresorbable amphiphiles as surface-active agents for stabilizing oily/aqueous interfaces and formed a colloidal vehicle named polysorbasome (PSS, polymeric absorbable vesicle), without using conventional emulsifiers such as sorbitan esters or their ethoxylates. Homogenizing the oil/water compartments forms a colloid containing an aqueous solution in its core and provides an oily barrier that isolates the encapsulated material from external materials. In this form, the PSS serves as a depot for sustained delivery of vaccine antigens. Following vaccination, the antigen-specific antibodies and the cell-mediated immunity can be manipulated after the antigen being formulated with PSS particles. Then, the degradability intrinsic to the polymeric bioresorbable amphiphiles complies with the destruction and further absorbance of the vehicles in vivo. The structural features of these versatile vesicles based on bioresorbable amphiphilic engineering may provide new insights into vaccine delivery.
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Implantes Absorvíveis , Coloides , Sistemas de Liberação de Medicamentos , Polímeros , VacinasRESUMO
The CYP11A1 encodes cytochrome P450scc, catalyzing the first step of steroidogenesis in adrenals and gonads under the control of cAMP-mediated hormonal signals. The cAMP-induced activation of human CYP11A1 has been suggested to depend on the transcription factor cAMP-responsive element-binding protein (CREB), but the CREB action cannot explain the chronic cAMP effect on CYP11A1 activation. To further understand the mechanism of human CYP11A1 activation, we dissected the functions of the upstream cAMP responsive sequences (U-CRS) containing a core sequence, U identical to the steroidogenic factor-1 (SF-1)-binding site, and two flanking TPA-responsive element/cAMP-responsive element-like elements, C1 and C2. The EMSA assays showed that the binding activities of U with SF-1 as well as C1 or C2 with activating protein-1 (AP-1)/CREB-like proteins are induced by cAMP. The results from the site-directed mutagenesis analyses revealed that all three elements are required for the U-CRS function and any mutation of C1, C2, or U impairs the response to cAMP stimulation. In transgenic mice, the single or double mutations of C1 and C2 resulted in the reduction of reporter gene expression accompanied with poor hormonal response. The cAMP induction on the U-CRS activity was mimicked and enhanced by the overexpressed c-Jun in the presence of SF-1, but was abolished by the overexpression of an AP-1 dominant-negative mutant, FosB2. Furthermore, we have observed the interdependent transactivation between SF-1 and c-Jun on the U-CRS function. These results collectively demonstrate that SF-1 and AP-1 cooperate to activate CYP11A1 transcription in vitro and in vivo.
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Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , AMP Cíclico/farmacologia , Proteínas de Homeodomínio/fisiologia , Receptores Citoplasmáticos e Nucleares/fisiologia , Fator de Transcrição AP-1/fisiologia , Fatores de Transcrição/fisiologia , Animais , Células Cultivadas , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Feminino , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Receptores Citoplasmáticos e Nucleares/metabolismo , Elementos Reguladores de Transcrição , Fator Esteroidogênico 1 , Fator de Transcrição AP-1/metabolismo , Fatores de Transcrição/metabolismo , Ativação Transcricional/efeitos dos fármacos , TransfecçãoRESUMO
This study describes the feasibility and adjuvant mechanism of a degradable emulsion for tuning adaptive immune responses to a vaccine antigen. We featured a mouse model with ovalbumin (OVA) as the antigen to deepen our understanding of the properties of a degradable emulsion-based adjuvant, dubbed PELC, interacting with immune cells and to elucidate their roles in vaccine immunogenicity in vivo. First, we demonstrated that the emulsion, which is stabilized by an amphiphilic bioresorbable polymer, shows degradation in mimic human body conditions and considerable tolerance in vivo. Then, we confirmed the model protein could be loaded into the emulsion and released from the matrix in a sustained manner, subsequently driving the production of antigen-specific antibodies. We also comprehended that PELC not only recruits antigen-presenting cells (APCs) to the injection site but also induces the activation of the recruited APCs and migration to the draining lymph nodes. As an adjuvant for cancer immunotherapy, PELC-formulated OVA could strongly enhance antigen-specific T-cell responses as well as anti-tumor ability with respected to non-formulated OVA, using OVA protein/EG7 cells as a tumor antigen/tumor cell model. Accordingly, our data paved the way for the clinical application of degradable emulsions based on amphiphilic bioresorbable polymers as vaccine adjuvants.