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Adjuvants play a critical role in the induction of effective immune responses by vaccines. Here, a self-assembling nanovaccine platform that integrates adjuvant functions into the delivery vehicle is prepared. Cationic Lentinan (CLNT) is mixed with ovalbumin (OVA) to obtain a self-assembling nanovaccine (CLNTO nanovaccine), which induces the uptake and maturation of bone marrow dendritic cells (BMDCs) via the toll-like receptors 2/4 (TLR2/4) to produce effective antigen cross-presentation. CLNTO nanovaccines target lymph nodes (LNs) and induce a robust OVA-specific immune response via TLR and tumor necrosis factor (TNF) signaling pathways, retinoic acid-inducible gene I (RIG-I) receptor, and cytokine-cytokine receptor interactions. In addition, CLNTO nanovaccines are found that promote the activation of follicular helper T (Tfh) cells and induce the differentiation of germinal center (GC) B cells into memory B cells and plasma cells, thereby enhancing the immune response. Vaccination with CLNTO nanovaccine significantly inhibits the growth of ovalbumin (OVA)-expressing B16 melanoma cell (B16-OVA) tumors, indicating its great potential for cancer immunotherapy. Therefore, this study presents a simple, safe, and effective self-assembling nanovaccine that induces helper T cell 1 (Th1) and helper T cell (Th2) immune responses, making it an effective vaccine delivery system.
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Micro- and nanoparticles delivery systems have been widely studied as vaccine adjuvants to enhance immunogenicity and sustain long-term immune responses. Polygonatum sibiricum polysaccharide (PSP) has been widely studied as an immunoregulator in improving immune responses. In this study, we synthesized and characterized cationic modified calcium carbonate (CaCO3) microparticles loaded with PSP (PEI-PSP-CaCO3, CTAB-PSP-CaCO3), studied the immune responses elicited by PEI-PSP-CaCO3 and CTAB-PSP-CaCO3 carrying ovalbumin (OVA). Our results demonstrated that PEI-PSP-CaCO3 significantly enhanced the secretion of IgG and cytokines (IL-4, IL-6, IFN-γ, and TNF-α) in vaccinated mice. Additionally, PEI-PSP-CaCO3 induced the activation of dendritic cells (DCs), T cells, and germinal center (GC) B cells in draining lymph nodes (dLNs). It also enhanced lymphocyte proliferation, increased the ratio of CD4+/CD8+ T cells, and elevated the frequency of CD3+ CD69+ T cells in spleen lymphocytes. Therefore, PEI-PSP-CaCO3 microparticles induced a stronger cellular and humoral immune response and could be potentially useful as a vaccine delivery and adjuvant system.
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Carbonato de Cálcio , Células Dendríticas , Polygonatum , Polissacarídeos , Animais , Camundongos , Carbonato de Cálcio/química , Polygonatum/química , Polissacarídeos/química , Células Dendríticas/imunologia , Células Dendríticas/efeitos dos fármacos , Feminino , Adjuvantes de Vacinas/química , Ovalbumina/imunologia , Ovalbumina/administração & dosagem , Citocinas/metabolismo , Camundongos Endogâmicos BALB C , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/administração & dosagem , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Nanopartículas/químicaRESUMO
Rosa laevigata Michx. polysaccharides (RLP) have been demonstrated to possess antioxidant and anti-inflammatory properties. However, the mechanisms and efficacy of these polysaccharide components in preventing ulcerative colitis (UC) remain to be elucidated. The efficacy and mechanisms of RLP were investigated in a study that utilized healthy adult beagles to establish a UC model, considering the similarities in gut microbiota between humans and dogs. In the study, the beagle model induced by sodium dextran sulfate exhibited typical symptoms of ulcerative colitis, such as weight loss and diarrhea. All these symptoms and changes were significantly ameliorated through oral supplementation of RLP. Additionally, microbial community analysis based on the 16S rDNA gene revealed that RLP alleviated UC by increasing the abundance of beneficial bacteria and reducing the abundance of harmful bacteria. In conclusion, our study has provided that RLP effectively alleviated colitis by preserving the intestinal barrier and regulating the gut microbiota composition.
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Colite Ulcerativa , Sulfato de Dextrana , Microbioma Gastrointestinal , Polissacarídeos , Rosa , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Cães , Microbioma Gastrointestinal/efeitos dos fármacos , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Rosa/química , Modelos Animais de Doenças , MasculinoRESUMO
Matrine (MT) possesses anti-inflammatory, anti-allergic and antioxidative properties. However, the impact and underlying mechanisms of matrine on colitis are unclear. The purpose of this research was to examine the protective impact and regulatory mechanism of matrine on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice. MT alleviated DSS-induced UC by inhibiting weight loss, relieving colon shortening and reducing the disease activity index (DAI). Moreover, DSS-induced intestinal injury and the number of goblet cells were reversed by MT, as were alterations in the expression of zonula occludens-1 (ZO-1) and occludin in colon. Simultaneously, matrine not only effectively restored DSS-induced oxidative stress in colonic tissues but also reduced the production of inflammatory cytokines. Furthermore, MT could treat colitis mice by regulating the regulatory T cell (Treg)/T helper 17 (Th17) cell imbalance. We observed further evidence that MT alleviated the decrease in intestinal flora diversity, reduced the proportion of Firmicutes and Bacteroidetes, decreased the proportion of Proteobacteria and increased the relative abundance of Lactobacillus and Akkermansia in colitis mice. In conclusion, these results suggest that MT may mitigate DSS-induced colitis by enhancing the colon barrier integrity, reducing the Treg/Th17 cell imbalance, inhibiting intestinal inflammation, modulating oxidative stress and regulating the gut microbiota. These findings provide strong evidence for the development and application of MT as a dietary treatment for UC.
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Alcaloides , Sulfato de Dextrana , Microbioma Gastrointestinal , Matrinas , Estresse Oxidativo , Quinolizinas , Linfócitos T Reguladores , Animais , Alcaloides/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Quinolizinas/farmacologia , Quinolizinas/uso terapêutico , Camundongos , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Masculino , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Colite/microbiologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Proteína da Zônula de Oclusão-1/metabolismo , Colo/patologia , Colo/metabolismo , Colo/efeitos dos fármacos , Colo/microbiologia , Células Th17/efeitos dos fármacos , Células Th17/metabolismo , Células Th17/imunologia , Modelos Animais de Doenças , Citocinas/metabolismo , Camundongos Endogâmicos C57BL , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/microbiologia , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Ocludina/metabolismoRESUMO
RLPa-2 (Mw 15.6 kDa) is a polysaccharide isolated from Rosa laevigata Michx. It consists of arabinose (Ara), galactose (Gal), rhamnose (Rha), glucose (Glc), xylose (Xyl), and galacturonic acid (Gal-UA) with a molar ratio of 1.00:0.91:0.39:0.34:0.25:0.20. Structural characterization was performed by methylation and NMR analysis, which indicated that RLPa-2 might comprise â6)-α-D-Galp-(1â, â4)-α-D-GalpA-(1â, α-L-Araf-(1â, â2,4)-α-D-Glcp-(1â, ß-D-Xylp, and α-L-Rhap. In addition, the bioactivity of RLPa-2 was assessed through an in vitro macrophage polarization assay. Compared to positive controls, there was a significant decrease in the expression of M1 macrophage markers (CD80, CD86) and p-STAT3/STAT3 protein. Additionally, there was a down-regulation in the production of pro-inflammatory mediators (NO, IL-6, TNF-α), indicating that M1 macrophage polarization induced with lipopolysaccharide (LPS) and interferon-γ (IFN-γ) stimulation could be inhibited by RLPa-2. These findings demonstrate that the RLPa-2 might be considered as a potential anti-inflammatory drug to reduce inflammation.
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Frutas , Rosa , Frutas/química , Rosa/química , Polissacarídeos/química , Macrófagos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/análiseRESUMO
Chinese yam polysaccharides (CYPs) have received wide attention for their immunomodulatory activity. Our previous studies had discovered that the Chinese yam polysaccharide PLGA-stabilized Pickering emulsion (CYP-PPAS) can serve as an efficient adjuvant to trigger powerful humoral and cellular immunity. Recently, positively charged nano-adjuvants are easily taken up by antigen-presenting cells, potentially resulting in lysosomal escape, the promotion of antigen cross-presentation, and the induction of CD8 T-cell response. However, reports on the practical application of cationic Pickering emulsions as adjuvants are very limited. Considering the economic damage and public-health risks caused by the H9N2 influenza virus, it is urgent to develop an effective adjuvant for boosting humoral and cellular immunity against influenza virus infection. Here, we applied polyethyleneimine-modified Chinese yam polysaccharide PLGA nanoparticles as particle stabilizers and squalene as the oil core to fabricate a positively charged nanoparticle-stabilized Pickering emulsion adjuvant system (PEI-CYP-PPAS). The cationic Pickering emulsion of PEI-CYP-PPAS was utilized as an adjuvant for the H9N2 Avian influenza vaccine, and the adjuvant activity was compared with the Pickering emulsion of CYP-PPAS and the commercial adjuvant (aluminum adjuvant). The PEI-CYP-PPAS, with a size of about 1164.66 nm and a ζ potential of 33.23 mV, could increase the H9N2 antigen loading efficiency by 83.99%. After vaccination with Pickering emulsions based on H9N2 vaccines, PEI-CYP-PPAS generated higher HI titers and stronger IgG antibodies than CYP-PPAS and Alum and increased the immune organ index of the spleen and bursa of Fabricius without immune organ injury. Moreover, treatment with PEI-CYP-PPAS/H9N2 induced CD4+ and CD8+ T-cell activation, a high lymphocyte proliferation index, and increased cytokine expression of IL-4, IL-6, and IFN-γ. Thus, compared with the CYP-PPAS and aluminum adjuvant, the cationic nanoparticle-stabilized vaccine delivery system of PEI-CYP-PPAS was an effective adjuvant for H9N2 vaccination to elicit powerful humoral and cellular immune responses.
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Vírus da Influenza A Subtipo H9N2 , Vacinas contra Influenza , Nanopartículas , Animais , Galinhas , Alumínio/farmacologia , Emulsões/farmacologia , Antígenos , Imunidade Celular , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Adjuvantes Imunológicos , Polissacarídeos/farmacologiaRESUMO
Staphylococcus saprophyticus is frequently involved in various difficult-to-treat infections due to the formation of biofilms. To identify useful antibiofilm strategies, this study explored the efficacy and mechanism of baicalin in enhancing the ability of azithromycin against multidrug-resistant Staphylococcus saprophyticus-Liu-2016-Liyang, China-francolin (MDRSS) biofilms in vitro and in vivo. When azithromycin was used in combination with baicalin, the minimum inhibitory concentration in biofilm (MICB) for azithromycin decreased 4- to 512-fold. Compared with the azithromycin and baicalin groups, the combination of azithromycin and baicalin could not reduce the biofilm biomass, but the dispersion rates of biofilm were decreased and the bactericidal ability was increased. Furthermore, the relative transcript levels of WalK/R system-related genes were upregulated by the addition of baicalin or azithromycin plus baicalin compared with that of the azithromycin and blank control groups. The strong correlation relationship between the WalK/R system and the bactericidal index demonstrated that baicalin enhanced the bactericidal effect of azithromycin on MDRSS biofilms by modulating the WalK/R system. In the mouse cutaneous infection model, the combination of azithromycin and baicalin succeeded in eradicating MDRSS and decreasing pathological injuries. This study indicated that baicalin has the potential to be an adjuvant to enhance the antimicrobial activity of azithromycin against MDRSS in the biofilm form by modulating the WalK/R system.
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Azitromicina , Staphylococcus aureus Resistente à Meticilina , Animais , Antibacterianos/farmacologia , Azitromicina/farmacologia , Biofilmes , Camundongos , Testes de Sensibilidade Microbiana/veterinária , Staphylococcus saprophyticusRESUMO
Human pose estimation has long been a fundamental problem in computer vision and artificial intelligence. Prominent among the 2D human pose estimation (HPE) methods are the regression-based approaches, which have been proven to achieve excellent results. However, the ground-truth labels are usually inherently ambiguous in challenging cases such as motion blur, occlusions, and truncation, leading to poor performance measurement and lower levels of accuracy. In this paper, we propose Cofopose, which is a two-stage approach consisting of a person and keypoint detection transformers for 2D human pose estimation. Cofopose is composed of conditional cross-attention, a conditional DEtection TRansformer (conditional DETR), and an encoder-decoder in the transformer framework; this allows it to achieve person and keypoint detection. In a significant departure from other approaches, we use conditional cross-attention and fine-tune conditional DETR for our person detection, and encoder-decoders in the transformers for our keypoint detection. Cofopose was extensively evaluated using two benchmark datasets, MS COCO and MPII, achieving an improved performance with significant margins over the existing state-of-the-art frameworks.
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Inteligência Artificial , Redes Neurais de Computação , Humanos , Movimento (Física)RESUMO
Hy-Line Brown chickens' health is closely related to poultry productivity and it is mainly maintained by the immune system, healthy intestinal function, and microflora of chicken. Polysaccharides are biological macromolecules with a variety of activities that can be used as a potential prebiotic to improve poultry health. In this experiment, the function of Alhagi honey polysaccharides (AH) as an immunomodulator on the chicken was investigated. All chicken (120) were randomly distributed to four groups (five replicas/group, six hens/replica). A total of 0.5 mL water was taken orally by the chicken in control group. AH (0.5 mL) in different concentrations (three dosages, 0.3 g/kg, 0.6 g/k, and 1.2 g/kg) were used for the AH-0.3 g/kg, AH-0.6 g/k, and AH-1.2 g/kg group, respectively. The results showed that the growth performance of the chickens and the index of immune organs (the weight of immune organs/the body weight) were enhanced significantly after being AH-treated (p < 0.05). The content of sIgA and cytokines was upregulated remarkably in the intestine after being AH-treated (p < 0.05). The AH treatment significantly enhanced the intestinal epithelial barrier (p < 0.05). Moreover, the percentage of CD4+ and CD8+ T cells in the ileum, spleen, and serum were obviously upscaled (p < 0.05). In addition, the AH treatment significantly enhanced the production of short chain fatty acids (SCFAs) and improved the structure of gut microbiota (p < 0.05). In conclusion, we found that AH-1.2g/kg was the best dosage to improve the chicken's health, and these data demonstrated that AH could be used as a potential tool to enhance growth performance through improving intestine function, immunity, and gut microbiome in chicken.
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Microbioma Gastrointestinal , Mel , Animais , Feminino , Linfócitos T CD8-Positivos , Galinhas , Imunidade , Intestinos , Polissacarídeos/farmacologiaRESUMO
Nanoparticle vaccine delivery systems have been emerging strategies for inducing potent immune responses to prevent and treat infectious diseases and cancers. The properties of nanoparticle vaccine delivery systems, such as nanoparticle size, surface charge, and antigen release kinetics, have been extensively studied and proven to effectively influence the efficacy of vaccine responses. However, a few types of research have focused on the influence of administration routes of nanoparticle vaccines on immune responses. Herein, to investigate how the administration routes affect the immune responses of nanoparticles vaccines, we developed a nanoparticles system (NPs), in which the ovalbumin (OVA) and Angelica sinensis polysaccharide (ASP) were incorporated into poly(lactic-co-glycolic acid) (PLGA) nanoparticles and the polyethylenimine (PEI) was coated on the surface of nanoparticles. The NPs vaccine was intramuscularly and subcutaneously injected (im and sc) into mice, and the immune responses induced by these two delivery routes were compared. The results showed that both im and sc administration of NPs vaccines elicited strong antigen-specific IgG, IgG1, and IgG2a antibody responses, with no significant difference. In contrast, NP vaccines with sc administration significantly enhanced immune responses, such as enhancing the recruitment and activation of dendritic cells (DCs) in lymph nodes (LNs), promoting the antigen transport into draining lymph nodes, increasing the secretion of cytokines, improving the ratio of CD4+T cells to CD8+ T cells, activating cytotoxic T lymphocyte response, and inducing a strong cellular immune response. These results may provide a new insight onto the development of vaccine delivery systems.
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Adjuvantes Imunológicos/química , Angelica sinensis/química , Sistemas de Liberação de Fármacos por Nanopartículas/química , Polissacarídeos/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Animais , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Feminino , Imunogenicidade da Vacina , Injeções Intramusculares , Injeções Subcutâneas , Camundongos , Modelos Animais , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Polietilenoimina/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Polissacarídeos/administração & dosagem , Desenvolvimento de Vacinas , Vacinas de Subunidades Antigênicas/imunologiaRESUMO
Ramulus mori polysaccharide (RMP), one of the most important active components of R. mori, has been attracting increasing interest because of its potent bioactive properties, including anti-inflammatory, antitumor, and antidiabetic effects. Despite the great therapeutic potential of RMP, its inherent properties of low bioavailability and brief biological half-life have limited its applications to the clinic. Thus, RMP was packaged by poly(lactic-co-glycolic acid) (PLGA) nanoparticles to develop a novel anti-inflammatory nanomedicine (PLGA-RMP) in this study. The nanoparticles were synthesized via a double-emulsion solvent evaporation technique, and the average diameter of PLGA-RMP was about 202 nm. PLGA-RMP nanoparticles reduced the expression of inflammatory cytokines while promoting the production of IL-10, and boosted the phenotypic shift in macrophages in vitro. Furthermore, lipopolysaccharide (LPS)-induced inflammatory bowel disease (IBD) in mouse was used to examine the anti-inflammatory effect of PLGA-RMP in vivo. Oral administration of PLGA-RMP in LPS-induced IBD mice substantially mitigated the intestinal inflammation compared to treatment with LPS alone, as evidenced by attenuation of disease activity index scores and inflammatory damage in the intestine. Meanwhile, PLGA-RMP suppressed the expression and secretion of specific inflammatory cytokines including TNF-α, IL-6, IL-1ß, and PGE2 in the inflamed intestine while inhibiting the activation of CD3+CD8+ T-cells and increasing the number of activated Tregs in the intestine. These results indicated that PLGA-RMP deserves further consideration as a potential therapeutic nanomedicine to treat various inflammatory diseases, including IBD.
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Anti-Inflamatórios/administração & dosagem , Doenças Inflamatórias Intestinais/tratamento farmacológico , Morus/química , Sistemas de Liberação de Fármacos por Nanopartículas/química , Polissacarídeos/administração & dosagem , Administração Oral , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Feminino , Humanos , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Células RAW 264.7RESUMO
Nanoparticle-based vaccine delivery systems have been extensively used to promote and induce immune responses to protein antigens. The properties of the nanoparticles, such as size, surface charge, and antigen loading mode, have been proved to significantly influence the adjuvant effect and immunoreactivity of nanoparticle-based vaccine delivery systems. The purpose of the study was to investigate how the surface charge and antigen loading mode of nanoparticles impact the immune responses. In this study, three ovalbumin (OVA)-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles with different surface charges and antigen loading modes were developed. The three nanoparticles were designed as antigen encapsulated with negatively charged (Angelica sinensis polysaccharide (ASP)-PLGA/OVA), antigen encapsulated with polyethylenimine (PEI)-coated (ASP-PLGA/OVA-PEI), and antigen adsorbed on PEI-coated (ASP-PLGA-PEI-OVA) nanoparticles. The Angelica sinensis polysaccharide (ASP) was used as the immunopotentiator and encapsulated into three nanoparticles. The results demonstrated that both PEI-coated (positively charged) nanoparticles promoted the antigen escape from the endosome, which led to the cytoplasmic antigen delivery to generate cross presentation, compared to negatively charged nanoparticles. In addition, PEI-coated nanoparticles activated the DCs in lymph nodes 5 days after the primary vaccination. In vivo experiments demonstrated that both antigen-encapsulated nanoparticles induced more potent and long-term antigen-specific antibody responses, compared to that of antigen-adsorbed nanoparticles. Thus, the PEI-coated and antigen-encapsulated nanoparticles (ASP-PLGA/OVA-PEI) as a vaccine adjuvant delivery system have the potential to induce strong and long-term humoral and cellular immune responses.
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Angelica sinensis/química , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Vacinas/administração & dosagem , Vacinas/química , Animais , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Células Cultivadas , Células Dendríticas/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Ensaio de Imunoadsorção Enzimática , Feminino , Imunidade Celular/fisiologia , Linfonodos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/química , Polietilenoimina/química , Polissacarídeos/químicaRESUMO
Rehmannia glutinosa polysaccharide (RGP) has been reported to exhibit anti-anxiety effects, yet the underlying mechanism remains unclear. Chronic constant light (CCL) induced cognitive dysfunction associated with oxidative stress in mice has been reported. Here, the neuroprotective effect of RGP on hippocampal neuron damage in CCL-treated mice was investigated. In vivo study, mice were subjected to CCL for 4 weeks and/or oral administration of 100, 200 and 400 mg/kg RGP every other day. In vitro experiment, hippocampal neuron cells (HT-22) was exposed to LED light and/or supplemented with 62.5, 125 and 250 µg/mL RGP. Mice exposed to CCL showed impaired cognitive and depressive-like behavior in the hippocampus, which were reversed by RGP. Meanwhile, RGP reversed light-induced oxidative stress and autophagy both in mice and hippocampal neuron cells (HT-22). Furthermore, compared with Light-exposed group, RGP treatment activated the AKT/mTOR pathway. Importantly, the AKT inhibitor Perifosine significantly weakened the neuroprotective of RGP on Light-induced oxidative stress and autophagy in HT-22 cells by inhibiting AKT/mTOR pathway and increasing the content of autophagy-related protein. Our data demonstrated, for the first time, that oxidative stress and the AKT/mTOR pathway plays a critical role in Light-induced apoptosis and autophagic cell death in mice and HT-22 cells.
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Morte Celular Autofágica , Fármacos Neuroprotetores , Rehmannia , Animais , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Rehmannia/metabolismo , Fármacos Neuroprotetores/farmacologia , Polissacarídeos/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Estresse Oxidativo , Autofagia , Hipocampo/metabolismoRESUMO
While research on mevalonate inhibitors as vaccine adjuvants has made great progress to enhance the effectiveness of the vaccine, co delivery of lovastatin and antigens (OVA) remains an enormous challenge. Here, we encapsulated lovastatin into PLGA nanoparticles. PLGA loading lovastatin was further emulsified with squalene to prepare Pickering emulsion. The emulsification conditions of Pickering emulsion were optimized, and the optimal preparation conditions were obtained. After loading lovastatin and OVA, the size and zeta potential of LS-PPAS/OVA was 1043.33 nm and -22.07 mv, the adsorption rate of OVA was 63.34 %. The adsorbing of LS-PLGA nanoparticles on the surface of squalene in Pickering emulsions was demonstrated by Fluorescent confocal microscopy. After immunization, LS-PPAS enhanced the activation of dendritic cells in lymph nodes, further study found LS-PPAS not only elicited elevated levels of OVA-specific IgG and its subtypes, but also promoted the secretion of TNF-α, IFN-γ, and IL-6 in serum as a marker of cellular immunity. Importantly, LS-PPAS showed sufficient security through monitoring levels of biochemical parameters in serum and pathological observation of organ following vaccinations. LS-PPAS may act as a promising vaccine carrier to produce strong humoral and cellular immunity with acceptable safety.
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Nanopartículas , Vacinas , Adjuvantes de Vacinas , Adjuvantes Imunológicos , Emulsões , Esqualeno/química , Nanopartículas/químicaRESUMO
Vaccines are an effective intervention for preventing infectious diseases. Currently many vaccine strategies are designed to improve vaccine efficacy by controlling antigen release, typically involving various approaches at the injection site. Yet, strategies for intracellular slow-release of antigens in vaccines are still unexplored. Our study showed that controlling the degradation of antigens in dendritic cells and slowing their transport from early endosomes to lysosomes markedly enhances both antigen-specific T-cell immune responses and germinal center B cell responses. This leads to the establishment of sustained humoral and cellular immunity in vivo imaging and flow cytometry indicated this method not only prolongs antigen retention at the injection site but also enhances antigen concentration in lymph nodes, surpassing traditional Aluminium (Alum) adjuvants. Additionally, we demonstrated that the slow antigen degradation induces stronger follicular helper T cell responses and increases proportions of long-lived plasma cells and memory B cells. Overall, these findings propose that controlling the speed of antigens transport in dendritic cells can significantly boost vaccine efficacy, offering an innovative avenue for developing highly immunogenic next-generation vaccines.
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Antígenos , Células Dendríticas , Imunidade Celular , Imunidade Humoral , Vacinas , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Animais , Imunidade Humoral/efeitos dos fármacos , Imunidade Humoral/imunologia , Vacinas/imunologia , Antígenos/imunologia , Imunidade Celular/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos , Feminino , Linfócitos B/imunologiaRESUMO
Here we report on the development and comprehensive evaluations of an mRNA vaccine for chronic hepatitis B (CHB) treatment. In two different HBV carrier mouse models generated by viral vector-mediated HBV transfection (pAAV-HBV1.2 and rAAV8-HBV1.3), this vaccine demonstrates sufficient and persistent virological suppression, and robust immunogenicity in terms of induction of strong innate immune activation, high-level virus-specific antibodies, memory B cells and T cells. mRNA platform therefore holds prospects for therapeutic vaccine development to combat CHB.
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The immune system acts as a vital defense barrier against pathogenic invasions, and its stable operation is crucial for maintaining body health. Nevertheless, various natural or artificial factors can compromise the body's immune function, leading to immunosuppression, which may interfere with the efficacy of vaccination and increase the susceptibility of the body to disease-causing pathogens. In an effort to ensure successful vaccinations and improve overall physical well-being, the search for appropriate immune regulators to enhance immunity is of paramount importance. Lentinan (LNT) has a significant role in immune regulation and vaccine adjuvants. In the present study, we constructed an immunosuppressive model using dexamethasone (DEX) and demonstrated that LNT could significantly improved antibody levels in immunosuppressive mice and stimulated T-lymphocyte proliferation and differentiation in intestinal Peyer's patches. LNT also increased the production of secretory immunoglobulin A (sIgA) in the duodenal fluid, the number of goblet cells, and the proportion of mucin area. Moreover, LNT modulated the intestinal microbiota and increased the production of short-chain fatty acids. Additionally, LNT promoted the proliferation, differentiation, and pro-inflammatory cytokines production of DEX-treated splenic T lymphocytes in vitro. Thus, the present study highlights the potential of LNT in reversing immunosuppression and avoiding the failure of vaccination.
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Terapia de Imunossupressão , Lentinano , Animais , Camundongos , Lentinano/farmacologia , Tolerância Imunológica , Intestinos , Dexametasona/farmacologiaRESUMO
Herpes zoster remains an important global health issue and mainly occurs in aged and immunocompromised individuals with an early exposure history to Varicella Zoster Virus (VZV). Although the licensed vaccine Shingrix has remarkably high efficacy, undesired reactogenicity and increasing global demand causing vaccine shortage urged the development of improved or novel VZV vaccines. In this study, we developed a novel VZV mRNA vaccine candidate (named as ZOSAL) containing sequence-optimized mRNAs encoding full-length glycoprotein E encapsulated in an ionizable lipid nanoparticle. In mice and rhesus macaques, ZOSAL demonstrated superior immunogenicity and safety in multiple aspects over Shingrix, especially in the induction of strong T-cell immunity. Transcriptomic analysis revealed that both ZOSAL and Shingrix could robustly activate innate immune compartments, especially Type-I IFN signalling and antigen processing/presentation. Multivariate correlation analysis further identified several early factors of innate compartments that can predict the magnitude of T-cell responses, which further increased our understanding of the mode of action of two different VZV vaccine modalities. Collectively, our data demonstrated the superiority of VZV mRNA vaccine over licensed subunit vaccine. The mRNA platform therefore holds prospects for further investigations in next-generation VZV vaccine development.
Assuntos
Vacina contra Herpes Zoster , Herpes Zoster , Animais , Camundongos , Macaca mulatta , Vacinas de mRNA , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3RESUMO
Pickering emulsion has great potential as a vaccine adjuvant due to its unique advantages such as its high antigen loading efficiency, great stability, etc. Among several adjuvants on the market, aluminum adjuvant (Alum) is the most widely used at present. However, problems such as the inability to effectively induce cellular immunity and the poor effect on subunit vaccines limit the application of Alum. As an immunopotentiator, Lycium barbarum polysaccharides (LBP) have been proven to have the ability to regulate humoral and cellular immunity. To overcome the insufficiency of Alum, we explored a new adjuvant delivery system. The Lycium barbarum polysaccharides-loaded Particulate Alum via Pickering emulsion (LBPPE) was prepared by loading Alum on the squalene/water interphase following LBP was adsorbed on the Alum surface (Fig. 10). Similar to squalene, LBPPE possesses a good biosafety profile. LBPPE was spherical with uneven surface, which increased the possibility of efficient antigen adsorption on the surface and crack of LBPPE. And the result shown that the LBPPE had high antigen loading rate at approximately 90 %. In vivo experiments, LBPPE showed an excellent ability to recruit antigen-presenting cells (APCs) at the injection sites, activate dendritic cells in the lymph nodes. Then, in the evaluation of humoral immunity, LBPPE was able to effectively induce the production of IgG, IgG1, and IgG2a. Moreover, LBPPE significantly enhanced the expression and activation of T lymphocytes, and induced a strong immune memory T cells response. All the results above suggested that LBPPE is likely to provide promising insights toward a safe and efficient adjuvant platform for vaccines.
Assuntos
Lycium , Animais , Camundongos , Emulsões/farmacologia , Esqualeno/farmacologia , Compostos de Alúmen/farmacologia , Adjuvantes Imunológicos , Imunidade Humoral , Antígenos , Adjuvantes Farmacêuticos/farmacologia , Polissacarídeos/farmacologia , Camundongos Endogâmicos BALB CRESUMO
Predicting human motion from historical pose sequence is crucial for a machine to succeed in intelligent interactions with humans. One aspect that has been obviated so far, is the fact that how we represent the skeletal pose has a critical impact on the prediction results. Yet there is no effort that investigates across different pose representation schemes. We conduct an indepth study on various pose representations with a focus on their effects on the motion prediction task. Moreover, recent approaches build upon off-the-shelf RNN units for motion prediction. These approaches process input pose sequence sequentially and inherently have difficulties in capturing long-term dependencies. In this paper, we propose a novel RNN architecture termed AHMR (Attentive Hierarchical Motion Recurrent network) for motion prediction which simultaneously models local motion contexts and a global context. We further explore a geodesic loss and a forward kinematics loss for the motion prediction task, which have more geometric significance than the widely employed L2 loss. Interestingly, we applied our method to a range of articulate objects including human, fish, and mouse. Empirical results show that our approach outperforms the state-of-the-art methods in short-term prediction and achieves much enhanced long-term prediction proficiency, such as retaining natural human-like motions over 50 seconds predictions. Our codes are released.