scholarly journals PMA Induces Vaccine Adjuvant Activity by the Modulation of TLR Signaling Pathway

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Dool-Ri Oh ◽  
Hu Won Kang ◽  
Jong-Ro Kim ◽  
Sunoh Kim ◽  
In-Kyu Park ◽  
...  
Keyword(s):  
Active Component ◽  
Mucosal Vaccine ◽  
Vaccine Adjuvant ◽  
Vaccine Adjuvants ◽  
Adjuvant Activity ◽  
Independent Manner ◽  
Etoh Extract ◽  
Croton Tiglium ◽  
Fractionation Column

Toll-like receptor (TLR) ligands are being developed for use as vaccine adjuvants and as immunomodulators because of their ability to stimulate innate and adaptive immune responses. Flagellin, a TLR5 ligand, was reported to show potent mucosal vaccine adjuvant activity. To identify ligands that potentiate the adjuvant activity of flagellin, we screened a plant library using HEK293T cells transiently cotransfected with phTLR5 and pNF-κB-SEAP plasmids. The 90% EtOH extract fromCroton tigliumshowed significant NF-κB transactivation in a TLR5-independent manner along with the increase of a flagellin activity. We have studied to characterize an active component fromCroton tigliumand to elucidate the action mechanisms. Phorbol 12-myristate 13-acetate (PMA) was isolated as an active component ofCroton tigliumby activity-guided fractionation, column chromatography, HPLC, NMR, and MS. PMA at a range of nM induced PKC-dependent NF-κB activation and IL-8 production in both TLR5− and TLR5+ assay systems. In in vivo mouse vaccination model, PMA induced antigen-specific IgG and IgA antibody responses and increased IL-12 production corresponding to T cell responses in spleen lymphocytes. These results suggest that PMA would serve as an efficacious mucosal vaccine adjuvant.

scholarly journals Essential Role of Host Double-Stranded DNA Released from Dying Cells by Cationic Liposomes for Mucosal Adjuvanticity

Vaccines ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 8
Author(s):  
Rui Tada ◽  
Akihiro Ohshima ◽  
Yuya Tanazawa ◽  
Akari Ohmi ◽  
Saeko Takahashi ◽  
...  
Keyword(s):  
Essential Role ◽  
Cationic Liposome ◽  
Cationic Liposomes ◽  
Mucosal Vaccine ◽  
Nasal Administration ◽  
Adjuvant Activity ◽  
Mucosal Adjuvant ◽  
Double Stranded Dna ◽  
Dying Cells

Infectious disease remains a substantial cause of death. To overcome this issue, mucosal vaccine systems are considered to be a promising strategy. Yet, none are approved for clinical use, except for live-attenuated mucosal vaccines, mainly owing to the lack of effective and safe systems to induce antigen-specific immune responses in the mucosal compartment. We have reported that intranasal vaccination of an antigenic protein, with cationic liposomes composed of 1,2-dioleoyl-3-trimethylammonium-propane and 3β-[N-(N′,N′-dimethylaminoethane)-carbamoyl], induced antigen-specific mucosal and systemic antibody responses in mice. However, precise molecular mechanism(s) underlying the mucosal adjuvant effects of cationic liposomes remain to be uncovered. Here, we show that a host double-stranded DNA (dsDNA), released at the site of cationic liposome injection, plays an essential role for the mucosal adjuvanticity of the cationic liposome. Namely, we found that nasal administration of the cationic liposomes induced localized cell death, at the site of injection, resulting in extracellular leakage of host dsDNA. Additionally, in vivo DNase I treatment markedly impaired OVA-specific mucosal and systemic antibody production exerted by cationic liposomes. Our report reveals that host dsDNA, released from local dying cells, acts as a damage-associated molecular pattern that mediates the mucosal adjuvant activity of cationic liposomes.

Tannic Acid Exhibits Adjuvant Activity by Enhancing Humoral and Cell-Mediated Immunity Against BSA as a Protein Antigen

2021 ◽  
Vol 28 ◽  
Author(s):  
Nidia Cabral-Hipólito ◽  
Brenda Sarahí Molina-Ramírez ◽  
Irais Castillo-Maldonado ◽  
Rocío Meza-Velázquez ◽  
Rubén García-Garza ◽  
...  
Keyword(s):  
Tannic Acid ◽  
Wistar Rats ◽  
Lethal Dose ◽  
Peritoneal Macrophages ◽  
Protein Antigen ◽  
Cell Mediated Immunity ◽  
Vaccine Adjuvants ◽  
Adjuvant Activity ◽  
Toxic Dose

Background: Immunization or vaccination is the process of inducing artificial immunity against an antigen taking advantage of the mechanisms of immunological memory. Current vaccines include substances known as adjuvants, which tend to improve the immunogenicity of the antigen, reduce the antigen quantity employed, and boost the immune response in weak responders. Unfortunately, only a few vaccine adjuvants are approved for human use. Objective: Thus, the objective of this study was to investigate the effect of Tannic acid on humoral and cell-mediated immunity against bovine serum albumin (BSA) as a protein antigen in Wistar rats. Method: In order to establish the Tannic acid concentration to test it as an adjuvant, the lethal dose 50 and maximum non-toxic dose were calculated through cytotoxicity and hemolytic assays with J774 A.1 cell line and rat erythrocytes by resazurin reduction method and UV/vis spectrophotometry. Thirty Wistar rats were divided into 5 groups that included two controls without antigen and three treatment groups of adjuvants plus BSA as a protein antigen. The rats were immunized in a 30-day scheme. Blood samples were collected for humoral immunity analysis by means of immunoglobulin quantification, isotyping and antigen-antibody precipitation inhibition analysis. Rat peritoneal macrophages and splenocytes were isolated for cell-mediated immunity analysis by means of nitric oxide quantification from adjuvant stimulated peritoneal macrophages and lymphocytes proliferation assay. Results: Tannic acid was capable of increasing the immunogenicity of the antigen; besides, it was able to stimulate cell-mediated immunity by means of increased lymphocyte proliferation. Moreover, Tannic acid improved the humoral response by means of increased specific antibodies titers. These activities may be attributed to pattern recognition receptors stimulation. Conclusion: Tannic acid was considered biocompatible when tested in vivo because the concentration tested did not show cytotoxicity or hemolytic effect, and there was no detrimental effect observed on the animals’ health. These results show Tannic acid as a promising candidate for vaccine adjuvant.

CAF01 liposomes as a mucosal vaccine adjuvant: In vitro and in vivo investigations

2010 ◽  
Vol 390 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Dennis Christensen ◽  
Camilla Foged ◽  
Ida Rosenkrands ◽  
Carina Vingsbo Lundberg ◽  
Peter Andersen ◽  
...  
Keyword(s):  
Mucosal Vaccine ◽  
Vaccine Adjuvant

scholarly journals Chemically Synthesized Alcaligenes Lipid A Shows a Potent and Safe Nasal Vaccine Adjuvant Activity for the Induction of Streptococcus pneumoniae-Specific IgA and Th17 Mediated Protective Immunity

2020 ◽  
Vol 8 (8) ◽  
pp. 1102
Author(s):  
Ken Yoshii ◽  
Koji Hosomi ◽  
Atsushi Shimoyama ◽  
Yunru Wang ◽  
Haruki Yamaura ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Mucosal Immunity ◽  
Lipid A ◽  
Biologically Active ◽  
Mucosal Vaccine ◽  
Vaccine Antigen ◽  
Vaccine Adjuvant ◽  
Vaccine Adjuvants ◽  
Cervical Lymph Nodes ◽  
Nasal Vaccine

Effective and safe vaccine adjuvants are needed to appropriately augment mucosal vaccine effects. Our previous study demonstrated that lipopolysaccharide (LPS) from Peyer’s patch resident Alcaligenes stimulated dendritic cells to promote the production of mucosal immunity-enhancing cytokines (e.g., IL-6 and BAFF), thus enhancing antigen-specific immune responses (including IgA production and Th17 responses) without excessive inflammation. Here, we chemically synthesized Alcaligenes lipid A, the biologically active part of LPS, and examined its efficacy as a nasal vaccine adjuvant for the induction of protectively immunity against Streptococcus pneumoniae infection. Mice were nasally immunized with pneumococcal surface protein A (PspA) as a vaccine antigen for S. pneumoniae, together with Alcaligenes lipid A. Alcaligenes lipid A supported the generation of high levels of PspA-specific IgA and IgG responses through the augmentation of germinal center formation in the nasopharynx-associated lymphoid tissue and cervical lymph nodes (CLNs). Moreover, Alcaligenes lipid A promoted PspA-specific CD4+ Th17 responses in the CLNs and spleen. Furthermore, neutrophils were recruited to infection sites upon nasal infection and synchronized with the antigen-specific T and B cell responses, resulting in the protection against S. pneumoniae infection. Taken together, Alcaligenes lipid A could be applied to the prospective adjuvant to enhance nasal vaccine efficacy by means of augmenting both the innate and acquired arms of mucosal immunity against respiratory bacterial infection.

scholarly journals Nasal Immunization With Small Molecule Mast Cell Activators Enhance Immunity to Co-Administered Subunit Immunogens

2021 ◽  
Vol 12 ◽  
Author(s):  
Brandi T. Johnson-Weaver ◽  
Hae Woong Choi ◽  
Hang Yang ◽  
Josh A. Granek ◽  
Cliburn Chan ◽  
...  
Keyword(s):  
Mast Cell ◽  
West Nile Virus ◽  
Small Molecule ◽  
High Throughput ◽  
High Throughput Screening ◽  
Mucosal Vaccine ◽  
Vaccine Adjuvants ◽  
West Nile ◽  
Adjuvant Activity ◽  
Nasal Vaccine

Mast cell activators are a novel class of mucosal vaccine adjuvants. The polymeric compound, Compound 48/80 (C48/80), and cationic peptide, Mastoparan 7 (M7) are mast cell activators that provide adjuvant activity when administered by the nasal route. However, small molecule mast cell activators may be a more cost-efficient adjuvant alternative that is easily synthesized with high purity compared to M7 or C48/80. To identify novel mast cell activating compounds that could be evaluated for mucosal vaccine adjuvant activity, we employed high-throughput screening to assess over 55,000 small molecules for mast cell degranulation activity. Fifteen mast cell activating compounds were down-selected to five compounds based on in vitro immune activation activities including cytokine production and cellular cytotoxicity, synthesis feasibility, and selection for functional diversity. These small molecule mast cell activators were evaluated for in vivo adjuvant activity and induction of protective immunity against West Nile Virus infection in BALB/c mice when combined with West Nile Virus envelope domain III (EDIII) protein in a nasal vaccine. We found that three of the five mast cell activators, ST101036, ST048871, and R529877, evoked high levels of EDIII-specific antibody and conferred comparable levels of protection against WNV challenge. The level of protection provided by these small molecule mast cell activators was comparable to the protection evoked by M7 (67%) but markedly higher than the levels seen with mice immunized with EDIII alone (no adjuvant 33%). Thus, novel small molecule mast cell activators identified by high throughput screening are as efficacious as previously described mast cell activators when used as nasal vaccine adjuvants and represent next-generation mast cell activators for evaluation in mucosal vaccine studies.

scholarly journals The mucosal adjuvant cyclic di-GMP enhances antigen uptake and selectively activates pinocytosis-efficient cells in vivo

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Steven M Blaauboer ◽  
Samira Mansouri ◽  
Heidi R Tucker ◽  
Hatti L Wang ◽  
Vincent D Gabrielle ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Cyclic Gmp ◽  
Mucosal Vaccine ◽  
Vaccine Adjuvant ◽  
Vaccine Response ◽  
Antigen Uptake ◽  
Mucosal Adjuvant ◽  
Adjuvanted Vaccine

Effective mucosal adjuvants enhance the magnitude and quality of the vaccine response. Cyclic di-GMP (CDG) is a promising mucosal vaccine adjuvant. However, its in vivo mechanisms are unclear. Here, we showed, in mice, that CDG elicits stronger Ab and TH responses than the mammalian 2′3′-cyclic GMP-AMP (cGAMP), and generated better protection against Streptococcus pneumoniae infection than 2′3′-cGAMP adjuvanted vaccine. We identified two in vivo mechanisms of CDG. First, intranasally administered CDG greatly enhances Ag uptake, including pinocytosis and receptor-mediated endocytosis in vivo. The enhancement depends on MPYS (STING, MITA) expression in CD11C+ cells. Second, we found that CDG selectively activated pinocytosis-efficient-DCs, leading to TH polarizing cytokines IL-12p70, IFNγ, IL-5, IL-13, IL-23, and IL-6 production in vivo. Notably, CDG induces IFNλ, but not IFNβ, in vivo. Our study revealed previously unrecognized in vivo functions of MPYS and advanced our understanding of CDG as a mucosal vaccine adjuvant.

scholarly journals Metformin induces Ferroptosis by inhibiting UFMylation of SLC7A11 in breast cancer

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Jingjing Yang ◽  
Yulu Zhou ◽  
Shuduo Xie ◽  
Ji Wang ◽  
Zhaoqing Li ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Treatment ◽  
Morphological Changes ◽  
Tumor Model ◽  
Independent Manner ◽  
Regulated Cell Death ◽  
Anti Cancer ◽  
Cancer Agent ◽  
Approved Drugs

Abstract Background Ferroptosis is a newly defined form of regulated cell death characterized by the iron-dependent accumulation of lipid peroxidation and is involved in various pathophysiological conditions, including cancer. Targeting ferroptosis is considered to be a novel anti-cancer strategy. The identification of FDA-approved drugs as ferroptosis inducers is proposed to be a new promising approach for cancer treatment. Despite a growing body of evidence indicating the potential efficacy of the anti-diabetic metformin as an anti-cancer agent, the exact mechanism underlying this efficacy has not yet been fully elucidated. Methods The UFMylation of SLC7A11 is detected by immunoprecipitation and the expression of UFM1 and SLC7A11 in tumor tissues was detected by immunohistochemical staining. The level of ferroptosis is determined by the level of free iron, total/lipid Ros and GSH in the cells and the morphological changes of mitochondria are observed by transmission electron microscope. The mechanism in vivo was verified by in situ implantation tumor model in nude mice. Results Metformin induces ferroptosis in an AMPK-independent manner to suppress tumor growth. Mechanistically, we demonstrate that metformin increases the intracellular Fe2+ and lipid ROS levels. Specifically, metformin reduces the protein stability of SLC7A11, which is a critical ferroptosis regulator, by inhibiting its UFMylation process. Furthermore, metformin combined with sulfasalazine, the system xc− inhibitor, can work in a synergistic manner to induce ferroptosis and inhibit the proliferation of breast cancer cells. Conclusions This study is the first to demonstrate that the ability of metformin to induce ferroptosis may be a novel mechanism underlying its anti-cancer effect. In addition, we identified SLC7A11 as a new UFMylation substrate and found that targeting the UFM1/SLC7A11 pathway could be a promising cancer treatment strategy.

scholarly journals Hypoxia promotes the metastasis of pancreatic cancer through regulating NOX4/KDM5A-mediated histone methylation modification changes in a HIF1A-independent manner

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Hongzhen Li ◽  
Chunyan Peng ◽  
Chenhui Zhu ◽  
Shuang Nie ◽  
Xuetian Qian ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Nadph Oxidase ◽  
Western Blot ◽  
Cancer Progression ◽  
Histone Methylation ◽  
Invasion And Metastasis ◽  
Independent Manner ◽  
Nadph Oxidase 4

Abstract Background Hypoxia is a characteristic of the tumor microenvironments within pancreatic cancer (PC), which has been linked to its malignancy. Recently, hypoxia has been reported to regulate the activity of important carcinogenic pathways by changing the status of histone modification. NOX4, a member of NADPH oxidase (NOX), has been found to be activated by hypoxia and promote cancer progression in several cancers. But whether it is involved in the epigenetic changes of tumor cells induced by hypoxia is still unclear, and its biological roles in PC also need to be explored. Methods A hypoxic-related gene signature and its associated pathways in PC were identified by analyzing the pancreatic cancer gene expression data from GEO and TCGA database. Candidate downstream gene (NOX4), responding to hypoxia, was validated by RT-PCR and western blot. Then, we evaluated the relationship between NOX4 expression and clinicopathologic parameters in 56 PC patients from our center. In vitro and in vivo assays were preformed to explore the phenotype of NOX4 in PC. Immunofluorescence, western blot and chromatin immunoprecipitation assays were further applied to search for a detailed mechanism. Results We quantified hypoxia and developed a hypoxia signature, which was associated with worse prognosis and elevated malignant potential in PC. Furthermore, we found that NADPH oxidase 4 (NOX4), which was induced by hypoxia and upregulated in PC in a HIF1A-independent manner, caused inactivation of lysine demethylase 5A (KDM5A), increased the methylation modification of histone H3 and regulated the transcription of EMT-associated gene_ snail family transcriptional repressor 1 (SNAIL1). This served to promote the invasion and metastasis of PC. NOX4 deficiency repressed hypoxia-induced EMT, reduced expression of H3K4ME3 and impaired the invasion and metastasis of PC cells; however, knockdown of KDM5A reversed the poor expression of H3KEME3 induced by NOX4 deficiency, thereby promoting EMT. Conclusions This study highlights the prognostic role of hypoxia-related genes in PC and strong correlation with EMT pathway. Our results also creatively discovered that NOX4 was an essential mediator for hypoxia-induced histone methylation modification and EMT in PC cells.

scholarly journals Telomere Formation by Rap1p Binding Site Arrays Reveals End-Specific Length Regulation Requirements and Active Telomeric Recombination

2001 ◽  
Vol 21 (23) ◽  
pp. 8117-8128 ◽  
Author(s):  
Simona Grossi ◽  
Alessandro Bianchi ◽  
Pascal Damay ◽  
David Shore
Keyword(s):  
Binding Sites ◽  
De Novo ◽  
Repeat Sequence ◽  
Independent Manner ◽  
Telomere Repeat ◽  
Length Regulation ◽  
End Capping ◽  
Original Array

ABSTRACT Rap1p, the major telomere repeat binding protein in yeast, has been implicated in both de novo telomere formation and telomere length regulation. To characterize the role of Rap1p in these processes in more detail, we studied the generation of telomeres in vivo from linear DNA substrates containing defined arrays of Rap1p binding sites. Consistent with previous work, our results indicate that synthetic Rap1p binding sites within the internal half of a telomeric array are recognized as an integral part of the telomere complex in an orientation-independent manner that is largely insensitive to the precise spacing between adjacent sites. By extending the lengths of these constructs, we found that several different Rap1p site arrays could never be found at the very distal end of a telomere, even when correctly oriented. Instead, these synthetic arrays were always followed by a short (≈100-bp) “cap” of genuine TG repeat sequence, indicating a remarkably strict sequence requirement for an end-specific function(s) of the telomere. Despite this fact, even misoriented Rap1p site arrays promote telomere formation when they are placed at the distal end of a telomere-healing substrate, provided that at least a single correctly oriented site is present within the array. Surprisingly, these heterogeneous arrays of Rap1p binding sites generate telomeres through a RAD52-dependent fusion resolution reaction that results in an inversion of the original array. Our results provide new insights into the nature of telomere end capping and reveal one way by which recombination can resolve a defect in this process.

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