Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 966
Filtrar
1.
Eur Biophys J ; 48(8): 743-747, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31630219

RESUMO

Published data on Factor C activity at various LPS and Lipid A concentrations (Nakamura et al. in Eur J Biochem 176:89, 1988; Kobayashi et al. in J Biol Chem 37:25987, 2014) were rearranged to show that Factor C exhibited its maximum activity at a specific concentration of LPS. A statistical model was proposed for examining whether a single LPS molecule binding activates Factor C (monomeric activation) or dimerization of Factor C is necessary for the activation (dimeric activation). In the monomeric activation model the plots of the relative activity of Factor C against the molar ratio of LPS to Factor C were different from those in the published data. The plots in the dimeric activation model lie on a bell-shaped curve, whatever the Factor C concentration, matching the published data and indicating the appropriateness of that model. We suggest that Factor C is activated by multiple molecular interactions of Factor C with LPS aggregates on which it dimerises and that this explains why larger aggregates are less effective at activating Factor C than smaller ones.


Assuntos
Proteínas de Artrópodes/metabolismo , Precursores Enzimáticos/metabolismo , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Modelos Moleculares , Serina Endopeptidases/metabolismo , Proteínas de Artrópodes/química , Precursores Enzimáticos/química , Lipídeo A/metabolismo , Lipídeo A/farmacologia , Lipopolissacarídeos/química , Ligação Proteica , Multimerização Proteica/efeitos dos fármacos , Estrutura Quaternária de Proteína , Serina Endopeptidases/química
2.
J Immunol Res ; 2019: 2121095, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31275998

RESUMO

The small intestine is one of the most sensitive organs to irradiation injury, and the development of high effective radioprotectants especially with low toxicity for intestinal radiation sickness is urgently needed. Monophosphoryl lipid A (MPLA) was found to be radioprotective in our previous study, while its effect against the intestinal radiation injury remained unknown. In the present study, we firstly determined the intestinal apoptosis after irradiation injury according to the TUNEL assay. Subsequently, we adopted the immunofluorescence technique to assess the expression levels of different biomarkers including Ki67, γ-H2AX, and defensin 1 in vivo. Additionally, the inflammatory cytokines were detected by RT-PCR. Our data indicated that MPLA could protect the intestine from ionizing radiation (IR) damage through activating TLR4 signal pathway and regulating the inflammatory cytokines. This research shed new light on the protective effect of the novel TLR4 agonist MPLA against intestine detriment induced by IR.


Assuntos
Enterite/etiologia , Enterite/metabolismo , Lipídeo A/análogos & derivados , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/patologia , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Citocinas/metabolismo , Dano ao DNA/efeitos dos fármacos , Modelos Animais de Doenças , Enterite/tratamento farmacológico , Enterite/patologia , Mediadores da Inflamação/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Lipídeo A/farmacologia , Camundongos , Camundongos Knockout , Lesões Experimentais por Radiação/tratamento farmacológico , Radiação Ionizante , Receptor 4 Toll-Like/deficiência
3.
Am J Physiol Renal Physiol ; 317(3): F705-F719, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31241993

RESUMO

LPS inhibits HCO3- absorption in the medullary thick ascending limb (MTAL) through a Toll-like receptor 4 (TLR4)-myeloid differentiation factor 88 (MyD88)-extracellular signal-regulated kinase (ERK) pathway that is upregulated by sepsis. Pretreatment with the nontoxic immunomodulator monophosphoryl lipid A (MPLA) prevents inhibition by LPS through activation of a TLR4-TIR-domain-containing adaptor-inducing interferon-ß (TRIF)-phosphatidylinositol 3-kinase (PI3K) pathway that prevents LPS-induced ERK activation. Here, we identified the molecular mechanisms that underlie the protective inhibitory interaction between the MPLA-PI3K and LPS-ERK pathways. Treatment of mouse MTALs with LPS in vitro increased phosphorylation of IL-1 receptor-associated kinase (IRAK)-1, a critical mediator of LPS signaling downstream of TLR4-MyD88. Activation of ERK by LPS was eliminated by a selective IRAK-1 inhibitor, establishing IRAK-1 as the upstream mediator of ERK activation. Pretreatment of MTALs with MPLA in vitro prevented LPS-induced IRAK-1 activation; this effect was dependent on PI3K. Treatment of MTALs with MPLA increased expression of Toll-interacting protein (Tollip), an inducible protein that negatively regulates LPS signaling by inhibiting IRAK-1. The MPLA-induced increase in Tollip protein level was prevented by PI3K inhibitors. In coimmunoprecipitation experiments, MPLA increased the amount of Tollip stably bound to IRAK-1, an interaction that inhibits IRAK-1 activation. These results support a mechanism whereby MPLA increases Tollip expression in the MTAL through a PI3K-dependent pathway. Tollip, in turn, inhibits LPS-induced TLR4 signaling by suppressing activation of IRAK-1, thereby preventing activation of ERK that inhibits HCO3- absorption. These studies show that MPLA induces reprogramming of MTAL cells that protects against LPS stimulation and identify IRAK-1 and Tollip as new therapeutic targets to prevent renal tubule dysfunction in response to infectious and inflammatory stimuli.


Assuntos
Adjuvantes Imunológicos/farmacologia , Bicarbonatos/metabolismo , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipídeo A/análogos & derivados , Alça do Néfron/efeitos dos fármacos , Reabsorção Renal/efeitos dos fármacos , Sepse/tratamento farmacológico , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Citoproteção , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Lipídeo A/farmacologia , Alça do Néfron/metabolismo , Alça do Néfron/fisiopatologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosforilação , Ratos Sprague-Dawley , Sepse/metabolismo , Sepse/fisiopatologia , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
4.
Phytomedicine ; 60: 152905, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31182297

RESUMO

BACKGROUND: Vaccine adjuvants are compounds that significantly enhance/prolong the immune response to a co-administered antigen. The limitations of the use of aluminium salts that are unable to elicite cell responses against intracellular pathogens such as those causing malaria, tuberculosis, or AIDS, have driven the development of new alternative adjuvants such as QS-21, a triterpene saponin purified from Quillaja saponaria. PURPOSE: The aim of this review is to attempt to clarify the mechanism of action of QS-21 through either receptors or signaling pathways in vitro and in vivo with special emphasis on the co-administration with other immunostimulants in new adjuvant formulations, called adjuvant systems (AS). Furthermore, the most relevant clinical applications will be presented. METHODS: A literature search covering the period 2014-2018 was performed using electronic databases from Sci finder, Science direct, Medline/Pubmed, Scopus, Google scholar. RESULTS: Insights into the mechanism of action of QS-21 can be summarized as follows: 1) in vivo stimulation of Th2 humoral and Th1 cell-mediated immune responses through action on antigen presenting cells (APCs) and T cells, leading to release of Th1 cytokines participating in the elimination of intracellular pathogens. 2) activation of the NLRP3 inflammasome in mouse APCs with subsequent release of caspase-1 dependent cytokines, Il-1ß and Il-18, important for Th1 responses. 3) synthesis of nearly 50 QS-21 analogs, allowing structure/activity relationships and mechanistic studies. 4) unique synergy mechanism between monophosphoryl lipid A (MPL A) and QS-21, formulated in a liposome (AS01) in the early IFN-γ response, promoting vaccine immunogenicity. The second part of the review is related to phase I-III clinical trials of QS-21, mostly formulated in ASs, to evaluate efficacy, immunogenicity and safety of adjuvanted prophylactic vaccines against infectious diseases, e.g. malaria, herpes zoster, tuberculosis, AIDS and therapeutic vaccines against cancer and Alzheimer's disease. CONCLUSION: The most advanced phase III clinical applications led to the development of two vaccines containing QS-21 as part of the AS, the Herpes Zoster vaccine (HZ/su) (Shingrix™) which received a license in 2017 from the FDA and a marketing authorization in the EU in 2018 and the RTS,S/AS01 vaccine (Mosquirix™) against malaria, which was approved by the EMA in 2015 for further implementation in Sub-Saharan countries for routine use.


Assuntos
Adjuvantes Imunológicos/farmacologia , Vacina contra Herpes Zoster/imunologia , Imunidade Celular/efeitos dos fármacos , Lipídeo A/análogos & derivados , Vacinas Antimaláricas/imunologia , Saponinas/farmacologia , Vacinas Sintéticas/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Células Apresentadoras de Antígenos/imunologia , Citocinas/imunologia , Inflamassomos/efeitos dos fármacos , Lipídeo A/administração & dosagem , Lipídeo A/farmacologia , Lipossomos/administração & dosagem , Camundongos , Saponinas/administração & dosagem , Linfócitos T/imunologia
5.
Neuroscience ; 408: 388-399, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31026566

RESUMO

Neuroinflammation plays an important role in epileptic disorders. Toll-like receptors (TLRs) are the key signal transduction tools by which neuroinflammation may promote epileptogenesis. Depending on the stimulus nature, TLRs may engage a distinct signaling pathway. We examined the impact of early minor activation of TLR4 and TLR2 on the severity of seizure in the pilocarpine rat model of temporal lobe epilepsy (TLE). One µg of Lipopolysaccharides (LPS), Monophosphoryl lipid A (MPL), Pam3Cysor or vehicles were microinjected into the right lateral ventricle of the male Wistar rats. 24 h later, seizures were induced by intraperitoneal injection of pilocarpine, and seizure-related behaviors were monitored. 24 h after seizure induction, the hippocampal level of pro/anti-inflammatory mediators and electrophysiological properties of the dentate gyrus (DG) granular cells were investigated by western blot and whole cell patch clamp techniques, respectively. Pretreatment with TLR ligands resulted in decreased seizure severity, lower hippocampal pro-inflammatory (IL-1ß and IL-6) cytokines and higher anti-inflammatory (IL-10 and TGF- ß) mediators in the pilocarpine-treated rats. Pilocarpine induced profound hyperexcitability in the DG granule cells accompanied by potentiated excitatory postsynaptic currents (EPSCs) and dampened inhibitory postsynaptic currents (IPSCs), in contrast to the control group. However, pretreatment with TLR ligands preserved almost normal excitability and synaptic transmission against the pilocarpine. In conclusion, early activation of TLR4 and TLR2, probably through preserving normal hippocampal cytokine profile and neuronal function attenuates seizure severity in the rat model of TLE.


Assuntos
Epilepsia/fisiopatologia , Lipídeo A/análogos & derivados , Lipopolissacarídeos/farmacologia , Neurônios/efeitos dos fármacos , Convulsões/fisiopatologia , Receptores Toll-Like/agonistas , Animais , Epilepsia/induzido quimicamente , Epilepsia/tratamento farmacológico , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Lipídeo A/farmacologia , Lipídeo A/uso terapêutico , Lipopolissacarídeos/uso terapêutico , Masculino , Técnicas de Patch-Clamp , Pilocarpina , Ratos , Ratos Wistar , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico
6.
Nano Lett ; 19(7): 4237-4249, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-30868883

RESUMO

Among approaches of current cancer immunotherapy, a dendritic cell (DC)-targeted vaccine based on nanotechnology could be a promising way to efficiently induce potent immune responses. To enhance DC targeting and vaccine efficiency, we included imiquimod (IMQ), a toll-like receptor 7/8 (TLR 7/8) agonist, and monophosphoryl lipid A (MPLA), a TLR4 agonist, to synthesize lipid-polymer hybrid nanoparticles using PCL-PEG-PCL and DOTAP (IMNPs) as well as DSPE-PEG-mannose (MAN-IMNPS). The spatiotemporal delivery of MPLA (within the outer lipid layer) to extracellular TLR4 and IMQ (in the hydrophobic core of NPs) to intracellular TLR7/8 can activate DCs synergistically to improve vaccine efficacy. Ovalbumin (OVA) as a model antigen was readily absorbed by positively charged DOTAP and showed a quick release in vitro. Our results demonstrated that this novel nanovaccine enhanced cellular uptake, cytokine production, and maturation of DCs. Compared with the quick metabolism of free OVA-agonists, the depot effect of OVA-IMNPs was observed, whereas MAN-OVA-IMNPs promoted trafficking to secondary lymphoid organs. After immunization with a subcutaneous injection, the nanovaccine, especially MAN-OVA-IMNPs, induced more antigen-specific CD8+ T cells, greater lymphocyte activation, stronger cross-presentation, and more generation of memory T cells, antibody, IFN-γ, and granzyme B. Prophylactic vaccination of MAN-OVA-IMNPs significantly delayed tumor development and prolonged the survival in mice. The therapeutic tumor challenge indicated that MAN-OVA-IMNPs prohibited tumor progression more efficiently than other formulations, and the combination with an immune checkpoint blockade further enhanced antitumor effects. Hence, the DC-targeted vaccine codelivery with IMQ and MPLA adjuvants by hybrid cationic nanoparticles in a spatiotemporal manner is a promising multifunctional antigen delivery system in cancer immunotherapy.


Assuntos
Antígenos de Neoplasias , Vacinas Anticâncer , Células Dendríticas/imunologia , Sistemas de Liberação de Medicamentos , Imiquimode , Imunoterapia , Lipídeo A/análogos & derivados , Nanopartículas , Neoplasias Experimentais , Receptores Toll-Like/agonistas , Animais , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/farmacologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/farmacocinética , Vacinas Anticâncer/farmacologia , Células Dendríticas/patologia , Imiquimode/imunologia , Imiquimode/farmacocinética , Imiquimode/farmacologia , Lipídeo A/imunologia , Lipídeo A/farmacocinética , Lipídeo A/farmacologia , Camundongos , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Receptores Toll-Like/imunologia
7.
APMIS ; 127(3): 150-157, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30746792

RESUMO

Monophosphoryl lipid A (MPL), a purified and detoxified product of lipopolysaccharide (LPS) of Salmonella minnesota R595, has been used as an adjuvant in different vaccines. In this study, the efficacy of human papillomaviruses (HPV) and hepatitis B virus (HBV) vaccines formulated with aluminum hydroxide combined with two different synthetic MPLs, 3D-(6-acyl)-PHAD or 3D-PHAD, or aluminum hydroxide combined with the mixtures of such MPLs, has been assessed. The immunogenicity in female BALB/c mice was verified by two intramuscular injections of differently formulated HPV and HBV vaccines and the total immunoglobulin G (IgG) antibody response was considered to compare the employed adjuvants. As verified experimentally, a mixture of 3D-(6-acyl)-PHAD and 3D-PHAD was able to induce significantly higher antibody titer than that of either 3D-(6-acyl)-PHAD or 3D-PHAD, when used individually. Interestingly, based on the responses achieved in terms of the total antibody levels, such mixture of synthetic MPLs was found to be even more effective than the bacterially derived MPL. Accordingly, the obtained results indicated that, if designed appropriately, synthetic MPL molecules could provide improved adjuvanticity with high level of consistency.


Assuntos
Adjuvantes Imunológicos/farmacologia , Hidróxido de Alumínio/farmacologia , Vacinas contra Hepatite B/imunologia , Fenômenos Imunogenéticos/efeitos dos fármacos , Lipídeo A/análogos & derivados , Vacinas contra Papillomavirus/imunologia , Adjuvantes Imunológicos/administração & dosagem , Hidróxido de Alumínio/imunologia , Animais , Anticorpos Antivirais/sangue , Feminino , Imunoglobulina G/sangue , Lipídeo A/síntese química , Lipídeo A/farmacologia , Camundongos Endogâmicos BALB C
8.
Mol Immunol ; 106: 159-169, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30623816

RESUMO

INTRODUCTION: The detoxified TLR4-ligand MPLA is a successfully used adjuvant in clinically approved vaccines. However, its capacity to activate glycolytic metabolism in mDC and the influence of MPLA-induced metabolic changes on cytokine secretion are unknown. AIM: To analyze the capacity of MPLA to activate mDC metabolism and the mechanisms contributing to MPLA-induced metabolism activation and cytokine secretion. METHODS: C57BL/6 bone-marrow-derived myeloid dendritic cells (mDCs) were stimulated with LPS or MPLA and analyzed for intracellular signaling, cytokine secretion, and metabolic state. mDC were pre-treated with rapamycin (mTOR-inhibitor), U0126, SP600125, SB202190 (MAPK kinase inhibitors), as well as dexamethasone (MAPK- and NFκB-inhibitor) and analyzed for MPLA-induced cytokine secretion and cell metabolic state. RESULTS: Stimulation of mDCs with either LPS or MPLA resulted in a pronounced, mTOR-dependent activation of glucose metabolism characterized by induction of the Warburg Effect, increased glucose consumption from the culture medium, as well as release of LDH. Compared to LPS, MPLA induced significantly lower cytokine secretion. The activation of mDC metabolism was comparable between LPS- and MPLA-stimulated mDCs. The MPLA-induced cytokine secretion could be partially inhibited using mTOR-, MAP kinase-, and NFκB-inhibitors, whereas the activation of glucose metabolism was shown to depend on both mTOR- and JNK-signaling. SUMMARY: The MPLA-induced activation of glycolytic metabolism in mouse mDC was shown to depend on a JNK-mediated activation of mTOR-signaling, while both MAPK- and NFB-signaling contributed to pro-inflammatory cytokine secretion. Understanding the mechanisms by which MPLA activates dendritic cells will both improve our understanding of its adjuvant properties and contribute to the future development and safe application of this promising adjuvant.


Assuntos
Adjuvantes Imunológicos/farmacologia , Células Dendríticas/imunologia , Glicólise/efeitos dos fármacos , Lipídeo A/análogos & derivados , MAP Quinase Quinase 4/imunologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Serina-Treonina Quinases TOR/imunologia , Animais , Citocinas/imunologia , Células Dendríticas/citologia , Glicólise/imunologia , Lipídeo A/farmacologia , Sistema de Sinalização das MAP Quinases/imunologia , Camundongos
9.
J Mol Neurosci ; 67(4): 495-503, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30610591

RESUMO

Soluble amyloid beta (Aß) oligomers are the most common forms of Aß in the early stage of Alzheimer's disease (AD). They are highly toxic to the neurons but their capability to activate microglia remains controversial. Microglia develop two distinct phenotypes, classic (M1) and alternative (M2). Tuning of microglia to the alternative (anti-inflammatory) state is of major interest in treatment of neuroinflammatory disease. This study aimed to assess tuning the microglia to produce interferon beta (IFN-ß) as an anti-inflammatory cytokine through TLR4 pathway in a rat model of AD. Microglial BV-2 cells were treated with 1 µg/ml lipopolysaccharides (LPS), Monophosphoryl lipid A (MPL), or vehicles for 24 h, and then incubated with Aß oligomer. After 24 h, cell pellets were harvested and TIR-domain-containing adapter-inducing interferon-ß (TRIF), interferon regulatory factor 3 (IRF3), and IFN-ß levels were measured. The ligands/vehicle were microinjected into the right ventricle of male Wistar rats every 3 days. Two weeks later, an osmotic pump filled with oligomeric Aß/vehicle was implanted in the left ventricle. After 2 weeks, TRIF, IRF3, and IFN-ß levels were measured in the hippocampal tissue. TNF-α and IFN-ß levels were assessed in the hippocampus using immunohistochemistry. The oligomeric Aß did not change TRIF, IRF3, and IFN-ß levels in both cell culture and hippocampal tissue. However, pretreatment with LPS or MPL increased the level of these proteins. BV-2 cells morphologically express M1 state in presence of higher dose of Aß oligomer (10 µM). Pretreatment with LPS or MPL decreased the TNF-α and increased the number of IFN-ß positive cells in the hippocampus of Aß-treated rats. In conclusion, pretreatment with low dose TLR4 agonists could induce microglia to produce neuroprotective cytokines including IFN-ß which may be considered as a potential strategy to combat neuronal degeneration in AD.


Assuntos
Doença de Alzheimer/metabolismo , Interferon beta/genética , Microglia/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Peptídeos beta-Amiloides/farmacologia , Animais , Linhagem Celular , Células Cultivadas , Hipocampo/metabolismo , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Interferon beta/metabolismo , Lipídeo A/análogos & derivados , Lipídeo A/farmacologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Microglia/efeitos dos fármacos , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
10.
Adv Healthc Mater ; 8(4): e1801091, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30565895

RESUMO

Cell membranes have recently gained attention as a promising drug delivery system. Here, dendritic cell membrane vesicles (DC-MVs) are examined as a platform to promote T cell responses. Nanosized DC-MVs are derived from DCs pretreated with monophosphoryl lipid A (MPLA), a FDA-approved immunostimulatory adjuvant. These "mature" DC-MVs activate DCs in vitro and increase their expression of costimulatory markers. DC-MVs also promote cross-priming of antigen-specific T cells in vitro, increasing their survival and CD25 expression. In addition, these mature DC-MVs potently augment the expansion of adoptively transferred CD8+ T cells in vivo, generating twofold to fourfold higher frequency of antigen-specific T cells, compared with other control formulations, including "immature" DC-MVs obtained without the MPLA pretreatment. Taken together, these results suggest that DC-MVs are an effective delivery platform for T cell activation and may serve as a potential delivery system for improving adoptive T cell therapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Ativação Linfocitária , Animais , Linfócitos T CD8-Positivos/citologia , Células Dendríticas/citologia , Subunidade alfa de Receptor de Interleucina-2/genética , Lipídeo A/análogos & derivados , Lipídeo A/farmacologia , Camundongos , Camundongos Transgênicos
11.
Cancer Res ; 79(1): 159-170, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30224373

RESUMO

Metastatic cancer involving spread to the peritoneal cavity is referred to as peritoneal carcinomatosis and has a very poor prognosis. Activating the antitumor immune response in the characteristically immune-suppressive peritoneal environment presents a potential strategy to treat this disease. In this study, we show that a toll-like receptor (TLR) and C-type lectin receptor (CLR) agonist pairing of monophosphoryl lipid A (MPL) and trehalose-6,6'-dicorynomycolate (TDCM) effectively inhibits tumor growth and ascites development in a mouse model of aggressive mammary cancer-induced peritoneal carcinomatosis. MPL/TDCM treatment similarly inhibited peritoneal EL4 tumor growth and ascites development. These effects were not observed in mice lacking B cells or mice lacking CD19, which are deficient in B-1a cells, an innate-like B-cell population enriched in the peritoneal cavity. Remarkably, adoptive transfer of B-1a cells, but not splenic B cells from WT mice, restored MPL/TDCM-induced protection in mice with B-cell defects. Treatment induced B-1 cells to rapidly produce high levels of natural IgM reactive against tumor-associated carbohydrate antigens. Consistent with this, we found significant deposition of IgM and C3 on peritoneal tumor cells as early as 5 days post-treatment. Mice unable to secrete IgM or complement component C4 were not protected by MPL/TDCM treatment, indicating tumor killing was mediated by activation of the classical complement pathway. Collectively, our findings reveal an unsuspected role for B-1 cell-produced natural IgM in providing protection against tumor growth in the peritoneal cavity, thereby highlighting potential opportunities to develop novel therapeutic strategies for the prevention and treatment of peritoneal metastases. SIGNIFICANCE: This work identifies a critical antitumor role for innate-like B cells localized within the peritoneal cavity and demonstrates a novel strategy to activate their tumor-killing potential.See related commentary by Tripodo, p. 5.


Assuntos
Subpopulações de Linfócitos B/imunologia , Imunidade Inata/imunologia , Imunoglobulina M/imunologia , Ativação Linfocitária/imunologia , Neoplasias Mamárias Animais/imunologia , Cavidade Peritoneal/patologia , Neoplasias Peritoneais/imunologia , Animais , Subpopulações de Linfócitos B/efeitos dos fármacos , Subpopulações de Linfócitos B/metabolismo , Subpopulações de Linfócitos B/patologia , Fatores Corda/farmacologia , Feminino , Imunidade Inata/efeitos dos fármacos , Imunoglobulina M/efeitos dos fármacos , Lectinas Tipo C/agonistas , Lipídeo A/análogos & derivados , Lipídeo A/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Neoplasias Mamárias Animais/tratamento farmacológico , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos C57BL , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/secundário , Receptores Toll-Like/agonistas
12.
Semin Immunol ; 39: 4-13, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30396811

RESUMO

The development of the CAF family adjuvant was initiated around 20 years ago when Statens Serum Institut was preparing its first generation protein based recombinant subunit vaccine against tuberculosis for clinical testing, but realized that there were no clinically relevant adjuvants available that would support the strong CMI response needed. Since then the aim for the adjuvant research at Statens Serum Institut has been to provide adjuvants with distinct immunogenicity profiles correlating with protection for any given infectious disease. Two of the adjuvants CAF01 and CAF09 are currently being evaluated in human clinical trials. The purpose of this review is to give an overview of the immunocorrelates of those CAF adjuvants furthest in development. We further aim at giving an overview of the mechanism of action of the CAF adjuvants.


Assuntos
Adjuvantes Imunológicos/farmacologia , Glicolipídeos/farmacologia , Imunidade Celular/efeitos dos fármacos , Imunogenicidade da Vacina , Lipídeo A/análogos & derivados , Compostos de Amônio Quaternário/farmacologia , Tuberculose Pulmonar/prevenção & controle , Adjuvantes Imunológicos/química , Animais , Glicolipídeos/química , Humanos , Imunidade Humoral/efeitos dos fármacos , Lipídeo A/química , Lipídeo A/farmacologia , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/imunologia , Camundongos , Compostos de Amônio Quaternário/química , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/microbiologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Células Th17/microbiologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia , Células Th2/microbiologia , Vacinas contra a Tuberculose/administração & dosagem , Vacinas contra a Tuberculose/química , Vacinas contra a Tuberculose/imunologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia
13.
Nat Nanotechnol ; 13(11): 1078-1086, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30374159

RESUMO

Microbial biochemicals have been indicated as the primary stimulators of innate immunity, the first line of the body's defence against infections. However, the influence of topological features on a microbe's surface on immune responses remains largely unknown. Here we demonstrate the ability of TiO2 microparticles decorated with nanospikes (spiky particles) to activate and amplify the immune response in vitro and in vivo. The nanospikes exert mechanical stress on the cells, which results in potassium efflux and inflammasome activation in macrophages and dendritic cells during phagocytosis. The spiky particles augment antigen-specific humoral and cellular immune responses in the presence of monophosphoryl lipid A and elicit protective immunity against tumour growth and influenza viral infection. The study offers insights into how surface physical cues can tune the activation of innate immunity and provides a basis for engineering particles with increased immunogenicity and adjuvanticity.


Assuntos
Células Dendríticas/imunologia , Macrófagos/imunologia , Nanopartículas , Fagocitose/efeitos dos fármacos , Titânio , Animais , Células Dendríticas/patologia , Vírus da Influenza A/imunologia , Lipídeo A/análogos & derivados , Lipídeo A/farmacologia , Macrófagos/patologia , Camundongos , Camundongos Knockout , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/terapia , Titânio/química , Titânio/farmacologia
14.
Semin Immunol ; 39: 22-29, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30366662

RESUMO

Lipopolysaccharide (LPS) is a well-defined agonist of Toll-like receptor (TLR) 4 that activates innate immune responses and influences the development of the adaptive response during infection with Gram-negative bacteria. Many years ago, Dr. Edgar Ribi separated the adjuvant activity of LPS from its toxic effects, an effort that led to the development of monophosphoryl lipid A (MPL). MPL, derived from Salmonella minnesota R595, has progressed through clinical development and is now used in various product-enabling formulations to support the generation of antigen-specific responses in several commercial and preclinical vaccines. We have generated several synthetic lipid A molecules, foremost glucopyranosyl lipid adjuvant (GLA) and second-generation lipid adjuvant (SLA), and have advanced these to clinical trial for various indications. In this review we summarize the potential and current positioning of TLR4-based adjuvant formulations in approved and emerging vaccines.


Assuntos
Adjuvantes Imunológicos/farmacologia , Compostos de Alúmen/farmacologia , Glucosídeos/farmacologia , Imunogenicidade da Vacina , Lipídeo A/análogos & derivados , Tuberculose/prevenção & controle , Adjuvantes Imunológicos/química , Compostos de Alúmen/química , Animais , Glucosídeos/química , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , Humanos , Imunidade Celular/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Leishmaniose/imunologia , Leishmaniose/parasitologia , Leishmaniose/prevenção & controle , Hanseníase/imunologia , Hanseníase/parasitologia , Hanseníase/prevenção & controle , Lipídeo A/química , Lipídeo A/farmacologia , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/imunologia , Malária/imunologia , Malária/parasitologia , Malária/prevenção & controle , Camundongos , Esquistossomose/imunologia , Esquistossomose/parasitologia , Esquistossomose/prevenção & controle , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/microbiologia , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia , Tuberculose/imunologia , Tuberculose/microbiologia , Vacinas/administração & dosagem , Vacinas/química , Vacinas/imunologia
15.
Neurochem Res ; 43(10): 1978-1985, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30173323

RESUMO

Five percent of all epilepsy cases are attributed to traumatic brain injury (TBI), which are known as post-traumatic epilepsy (PTE). Finding preventive strategies for PTE is valuable. Remarkable feature of TBI is activation of microglia and subsequent neuroinflammation, which provokes epileptogenesis. The toll-like receptor agonists monophosphoryl lipid A (MPL) and tri-palmitoyl-S-glyceryl-cysteine (Pam3Cys) are safe, well-tolerated and effective adjuvants existing in prophylactic human vaccines. We examined the impact of early injection of MPL and Pam3Cys to rats, on the rate of kindled seizures acquisition following TBI. Rats received a single dose (1 µg/rat) of MPL or Pam3Cys through intracerebroventricular injection. 5 days later, trauma was exerted to temporo-parietal cortex of rats by controlled cortical impact device. After 24 h, traumatic rats underwent amygdala kindling. Brain level of the inflammatory cytokine tumor necrosis factor-alpha (TNF-α) was also measured in traumatic rats by immunoblotting. Compared to non-traumatic (sham-operated) rats, traumatic rats showed three times lower seizure threshold (133 ± 5 µA vs. 416.3 ± 16 µA, p < 0.001); about three times less number of stimuli to become kindled (5 ± 1 vs. 14 ± 2, p < 0.01); longer duration of kindled seizure parameters including entire seizure behavior, generalized seizures, and afterdischarges (p < 0.001); and a two times increase in the TNF-α level. MPL and Pam3Cys did not change kindling rate and the seizure parameters in sham-operated rats. The MPL- and Pam3Cys-pretreated traumatic rats displayed seizure threshold, speed of kindling, and duration of kindled seizure parameters, similar to the non-traumatic rats. Pretreatment by MPL and Pam3Cys prevented the increase in TNF-α level by trauma. Given that MPL and Pam3Cys currently have clinical use as well-tolerated vaccines with reliable safety, they have the potential to be used in prevention of PTE.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Lipídeo A/análogos & derivados , Lipoproteínas/farmacologia , Convulsões/prevenção & controle , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/fisiologia , Animais , Encéfalo/fisiopatologia , Epilepsia/fisiopatologia , Epilepsia Pós-Traumática/tratamento farmacológico , Excitação Neurológica/efeitos dos fármacos , Lipídeo A/farmacologia , Masculino , Ratos Wistar
16.
Sci Adv ; 4(9): eaas9930, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30221194

RESUMO

Adjuvants are key to shaping the immune response to vaccination, but to date, no adjuvant suitable for human use has been developed for intradermal vaccines. These vaccines could be self-administered and sent through the mail as they do not require long needles or technical expertise in immunization. In the event of a pandemic outbreak, this approach could alleviate the congregation of patients in health centers and thus reduce the potential of these centers to enhance the spread of lethal infection. A reliable and potent vaccine system for self-administration would provide an effective countermeasure for delivery through existing product distribution infrastructure. We report results from preclinical and clinical trials that demonstrate the feasibility of an adjuvanted, intradermal vaccine that induced single shot protection in ferrets and seroprotection in humans against one of the more lethal strains of pandemic flu, Indonesia H5N1. In the human trial, the vaccine was safe and clinical responses were above approvable endpoints for a protective flu vaccine. Inclusion of a modern TLR4 (Toll-like receptor 4) agonist-based adjuvant was critical to the development of the response in the intradermal groups. In humans, this is the first report of a safe and effective intradermal adjuvant, GLA-AF (aqueous formulation of glucopyranosyl lipid adjuvant), and provides a future path for developing a vaccine-device combination for distribution by mail and self-administration in case of a pandemic.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/imunologia , Adjuvantes Imunológicos/farmacologia , Vacinas contra Influenza/farmacologia , Lipídeo A/análogos & derivados , 1,2-Dipalmitoilfosfatidilcolina/efeitos adversos , 1,2-Dipalmitoilfosfatidilcolina/farmacologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/efeitos adversos , Adulto , Animais , Combinação de Medicamentos , Feminino , Furões , Cobaias , Humanos , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/imunologia , Virus da Influenza A Subtipo H5N1/patogenicidade , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/efeitos adversos , Injeções Intradérmicas , Lipídeo A/efeitos adversos , Lipídeo A/imunologia , Lipídeo A/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Receptor 4 Toll-Like/agonistas
17.
Expert Rev Respir Med ; 12(11): 941-955, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30221563

RESUMO

INTRODUCTION: Airway inflammatory disorders are prevalent diseases in need of better management and new therapeutics. Immunotherapies offer a solution to the problem of corticosteroid resistance. Areas covered: The current review focuses on lipopolysaccharide (Gram-negative bacterial endotoxin)-mediated inflammation in the lung and the animal models used to study related diseases. Endotoxin-induced lung pathology is usually initiated by antigen presenting cells (APC). We will discuss different subsets of APC including lung dendritic cells and macrophages, and their role in responding to endotoxin and environmental challenges. Expert commentary: The pharmacotherapeutic considerations to combat airway inflammation should cost-effectively improve quality of life with sustainable and safe strategies. Selectively targeting APCs in the lung offer the potential for a promising new strategy for the better management and treatment of inflammatory lung disease.


Assuntos
Asma/imunologia , Endotoxinas/imunologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Alérgenos/imunologia , Animais , Anti-Inflamatórios/farmacologia , Bactérias/imunologia , Moléculas de Adesão Celular/metabolismo , Modelos Animais de Doenças , Portadores de Fármacos/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Imunidade Inata , Lipídeo A/análogos & derivados , Lipídeo A/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/imunologia , Células Mieloides/imunologia , Nanopartículas , Neutrófilos/metabolismo , Inibidores de Proteases/farmacologia , Síndrome do Desconforto Respiratório do Adulto/imunologia , Receptores Toll-Like/metabolismo
18.
Semin Immunol ; 39: 30-34, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30122362

RESUMO

The discovery and wide spread use of vaccines have saved millions of lives in the past few decades. Vaccine adjuvants represent an integral part of the modern vaccines. Despite numerous efforts, however, only a handful of vaccine adjuvants is currently available for human use. A comprehensive understanding of the mechanisms of action of adjuvants is pivotal to harness the potential of existing and new adjuvants in mounting desirable immune responses to counter human pathogens. Decomposing the host response to vaccines and its components at systems level has recently been made possible owing to the recent advancements in Omics technology and cutting edge immunological assays powered by systems biology approaches. This approach has begun to shed light on the molecular signatures of several human vaccines and adjuvants. This review is an attempt to provide an overview of the recent efforts in systems analysis of vaccine adjuvants that are currently in clinic.


Assuntos
Adjuvantes Imunológicos/farmacologia , Infecções por HIV/prevenção & controle , Imunogenicidade da Vacina , Influenza Humana/prevenção & controle , Malária Falciparum/prevenção & controle , Análise de Sistemas , Adjuvantes Imunológicos/química , Animais , Combinação de Medicamentos , Glucosídeos/química , Glucosídeos/farmacologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Imunidade Inata/efeitos dos fármacos , Influenza Humana/imunologia , Influenza Humana/virologia , Lipídeo A/química , Lipídeo A/farmacologia , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/imunologia , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Polissorbatos/química , Polissorbatos/farmacologia , Esqualeno/química , Esqualeno/farmacologia , Biologia de Sistemas , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/microbiologia , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia , Vacinas/administração & dosagem , Vacinas/química , Vacinas/imunologia , alfa-Tocoferol/química , alfa-Tocoferol/farmacologia
19.
Cytotherapy ; 20(9): 1164-1181, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30122654

RESUMO

BACKGROUND: Many efforts have been devoted to improve the performance of dendritic cell (DC)-based cancer vaccines. Ideally, a DC vaccine should induce robust type 1-polarized T-cell responses and efficiently expand antigen (Ag)-specific cytotoxic T-cells, while being applicable regardless of patient human leukocyte antigen (HLA) type. Production time should be short, while maximally being good manufacturing practice (GMP)-compliant. We developed a method that caters to all of these demands and demonstrated the superiority of the resulting product compared with DCs generated using a well-established "classical" protocol. METHODS: Immunomagnetically purified monocytes were cultured in a closed system for 3 days in GMP-compliant serum-free medium and cytokines, and matured for 24 h using monophosphoryl lipid A (MPLA)+ interferon-gamma (IFN-γ). Mature DCs were electroporated with messenger RNA (mRNA) encoding full-length antigen and cryopreserved. "Classical" DCs were cultured for 8 days in flasks, with one round of medium and cytokine supplementation, and matured with tumor necrosis factor alpha (TNF-α) + prostaglandin E2 (PGE2) during the last 2 days. RESULTS: Four-day MPLA/IFN-γ-matured DCs were superior to 8-day TNF-α/PGE2-matured DCs in terms of yield, co-stimulatory/co-inhibitory molecule expression, resilience to electroporation and cryopreservation and type 1-polarizing cytokine and chemokine release after cell thawing. Electroporated and cryopreserved DCs according to our protocol efficiently present epitopes from tumor antigen-encoding mRNA, inducing a strong expansion of antigen-specific CD8+ T-cells with full cytolytic capacity. CONCLUSION: We demonstrate using a GMP-compliant culture protocol the feasibility of generating high yields of mature DCs in a short time, with a superior immunogenic profile compared with 8-day TNF-α/PGE2-matured DCs, and capable of inducing vigorous cytotoxic T-cell responses to antigen from electroporated mRNA. This method is now being applied in our clinical trial program.


Assuntos
Vacinas Anticâncer , Técnicas de Cultura de Células/métodos , Células Dendríticas/citologia , RNA Mensageiro , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Diferenciação Celular , Criopreservação , Células Dendríticas/imunologia , Dinoprostona/farmacologia , Eletroporação , Epitopos , Humanos , Interferon gama/farmacologia , Lipídeo A/análogos & derivados , Lipídeo A/farmacologia , Monócitos/citologia , RNA Mensageiro/genética , Linfócitos T Citotóxicos/imunologia , Fator de Necrose Tumoral alfa/farmacologia
20.
Am J Physiol Renal Physiol ; 315(3): F711-F725, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29741098

RESUMO

Metabolic acidosis is the most common acid-base disorder in septic patients and is associated with increased mortality. Previously, we demonstrated that sepsis induced by cecal ligation and puncture (CLP) impairs [Formula: see text] absorption in the medullary thick ascending limb (MTAL) by 1) decreasing the intrinsic [Formula: see text] absorptive capacity and 2) enhancing inhibition of [Formula: see text] absorption by LPS through upregulation of Toll-like receptor (TLR) 4 signaling. Both effects depend on ERK activation. Monophosphoryl lipid A (MPLA) is a detoxified TLR4 agonist that enhances innate antimicrobial immunity and improves survival following sepsis. Pretreatment of MTALs with MPLA in vitro prevents LPS inhibition of [Formula: see text] absorption. Here we examined whether pretreatment with MPLA would protect the MTAL against sepsis. Vehicle or MPLA was administered to mice 48 h before sham or CLP surgery, and MTALs were studied in vitro 18 h postsurgery. Pretreatment with MPLA prevented the effects of sepsis to decrease the basal [Formula: see text] absorption rate and enhance inhibition by LPS. These protective effects were mediated through MPLA stimulation of a Toll/IL-1 receptor domain-containing adaptor-inducing IFN-ß-(TRIF)-dependent phosphatidylinositol 3-kinase-Akt pathway that prevents sepsis- and LPS-induced ERK activation. The effects of MPLA to improve MTAL [Formula: see text] absorption were associated with marked improvement in plasma [Formula: see text] concentration, supporting a role for the kidneys in the pathogenesis of sepsis-induced metabolic acidosis. These studies support detoxified TLR4-based immunomodulators, such as MPLA, that enhance antimicrobial responses as a safe and effective approach to prevent or treat sepsis-induced renal tubule dysfunction and identify cell signaling pathways that can be targeted to preserve MTAL [Formula: see text] absorption and attenuate metabolic acidosis during sepsis.


Assuntos
Acidose/prevenção & controle , Bicarbonatos/metabolismo , Lipídeo A/análogos & derivados , Alça do Néfron/efeitos dos fármacos , Reabsorção Renal/efeitos dos fármacos , Sepse/tratamento farmacológico , Equilíbrio Ácido-Base/efeitos dos fármacos , Acidose/metabolismo , Acidose/fisiopatologia , Proteínas Adaptadoras de Transporte Vesicular/deficiência , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Bicarbonatos/sangue , Bicarbonatos/urina , Modelos Animais de Doenças , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Lipídeo A/farmacologia , Alça do Néfron/metabolismo , Alça do Néfron/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sepse/metabolismo , Sepse/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/agonistas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA