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1.
Front Immunol ; 15: 1365015, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39391311

RESUMO

Inflammation plays a pivotal role in the pathogenesis of primary and post-essential thrombocythemia or post-polycythemia vera myelofibrosis (MF) in close cooperation with the underlying molecular drivers. This inflammatory state is induced by a dynamic spectrum of inflammatory cytokines, although recent evidence points to the participation of additional soluble inflammatory mediators. Damage-associated molecular patterns (DAMPs) represent endogenous signals released upon cell death or damage which trigger a potent innate immune response. We assessed the contribution of two prototypical DAMPs, HMGB1 and S100A8/A9, to MF inflammation. Circulating HMGB1 and S100A8/A9 were elevated in MF patients in parallel to the degree of systemic inflammation and levels increased progressively during advanced disease stages. Patients with elevated DAMPs had higher frequency of adverse clinical features, such as anemia, and inferior survival, suggesting their contribution to disease progression. Monocytes, which are key players in MF inflammation, were identified as a source of S100A8/A9 but not HMGB1 release, while both DAMPs correlated with cell death parameters, such as serum LDH and cell-free DNA, indicating that passive release is an additional mechanism leading to increased DAMPs. HMGB1 and S100A8/A9 promote inflammation through binding to Toll-like receptor (TLR) 4, whereas the former also binds TLR2. Monocytes from MF patients were shown to be hyperactivated at baseline, as reflected by higher CD11b and tissue factor exposure and increased expression levels of proinflammatory cytokines IL-1ß and IL-6. Patient monocytes showed preserved TLR4 and TLR2 expression and were able to mount normal or even exacerbated functional responses and cytokine upregulation following stimulation of TLR4 and TLR2. Elevated levels of endogenous TLR ligands HMGB1 and S100A8/A9 coupled to the finding of preserved or hyperreactive TLR-triggered responses indicate that DAMPs may promote monocyte activation and cytokine production in MF, fueling inflammation. Plasma IL-1ß and IL-6 were elevated in MF and correlated with DAMPs levels, raising the possibility that DAMPs could contribute to cytokine generation in vivo. In conclusion, this study highlights that, in cooperation with classic proinflammatory cytokines, DAMPs represent additional inflammatory mediators that may participate in the generation of MF inflammatory state, potentially providing novel biomarkers of disease progression and new therapeutic targets.


Assuntos
Alarminas , Calgranulina A , Calgranulina B , Proteína HMGB1 , Inflamação , Monócitos , Mielofibrose Primária , Humanos , Proteína HMGB1/sangue , Proteína HMGB1/metabolismo , Calgranulina A/sangue , Calgranulina B/sangue , Masculino , Feminino , Monócitos/imunologia , Monócitos/metabolismo , Idoso , Pessoa de Meia-Idade , Alarminas/metabolismo , Alarminas/imunologia , Inflamação/imunologia , Mielofibrose Primária/imunologia , Mielofibrose Primária/metabolismo , Idoso de 80 Anos ou mais , Receptores Toll-Like/metabolismo , Citocinas/metabolismo , Adulto , Receptor 4 Toll-Like/metabolismo , Biomarcadores
2.
Int J Mol Sci ; 24(21)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37958859

RESUMO

Cardiorenal syndrome type 4 (CRS type 4) occurs when chronic kidney disease (CKD) leads to cardiovascular damage, resulting in high morbidity and mortality rates. Mitochondria, vital organelles responsible for essential cellular functions, can become dysfunctional in CKD. This dysfunction can trigger inflammatory responses in distant organs by releasing Damage-associated molecular patterns (DAMPs). These DAMPs are recognized by immune receptors within cells, including Toll-like receptors (TLR) like TLR2, TLR4, and TLR9, the nucleotide-binding domain, leucine-rich-containing family pyrin domain-containing-3 (NLRP3) inflammasome, and the cyclic guanosine monophosphate (cGMP)-adenosine monophosphate (AMP) synthase (cGAS)-stimulator of interferon genes (cGAS-STING) pathway. Activation of these immune receptors leads to the increased expression of cytokines and chemokines. Excessive chemokine stimulation results in the recruitment of inflammatory cells into tissues, causing chronic damage. Experimental studies have demonstrated that chemokines are upregulated in the heart during CKD, contributing to CRS type 4. Conversely, chemokine inhibitors have been shown to reduce chronic inflammation and prevent cardiorenal impairment. However, the molecular connection between mitochondrial DAMPs and inflammatory pathways responsible for chemokine overactivation in CRS type 4 has not been explored. In this review, we delve into mechanistic insights and discuss how various mitochondrial DAMPs released by the kidney during CKD can activate TLRs, NLRP3, and cGAS-STING immune pathways in the heart. This activation leads to the upregulation of chemokines, ultimately culminating in the establishment of CRS type 4. Furthermore, we propose using chemokine inhibitors as potential strategies for preventing CRS type 4.


Assuntos
Síndrome Cardiorrenal , Insuficiência Renal Crônica , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de Sinais , Mitocôndrias/metabolismo , Nucleotidiltransferases/metabolismo , Receptores Imunológicos/metabolismo , Alarminas/metabolismo , Quimiocinas/metabolismo , Insuficiência Renal Crônica/metabolismo
3.
Int J Mol Sci ; 24(18)2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37762475

RESUMO

Stressed organisms identify intracellular molecules released from damaged cells due to trauma or pathogen infection as components of the innate immune response. These molecules called DAMPs (Damage-Associated Molecular Patterns) are extracellular ATP, sugars, and extracellular DNA, among others. Animals and plants can recognize their own DNA applied externally (self-exDNA) as a DAMP with a high degree of specificity. However, little is known about the microalgae responses to damage when exposed to DAMPs and specifically to self-exDNAs. Here we compared the response of the oilseed microalgae Neochloris oleoabundans to self-exDNA, with the stress responses elicited by nonself-exDNA, methyl jasmonate (MeJA) and sodium bicarbonate (NaHCO3). We analyzed the peroxidase enzyme activity related to the production of reactive oxygen species (ROS), as well as the production of polyphenols, lipids, triacylglycerols, and phytohormones. After 5 min of addition, self-exDNA induced peroxidase enzyme activity higher than the other elicitors. Polyphenols and lipids were increased by self-exDNA at 48 and 24 h, respectively. Triacylglycerols were increased with all elicitors from addition and up to 48 h, except with nonself-exDNA. Regarding phytohormones, self-exDNA and MeJA increased gibberellic acid, isopentenyladenine, and benzylaminopurine at 24 h. Results show that Neochloris oleoabundans have self-exDNA specific responses.


Assuntos
Clorofíceas , Microalgas , Animais , Reguladores de Crescimento de Plantas , Peroxidase , Alarminas , Corantes , DNA , Oxilipinas , Peroxidases
5.
Eur J Pharmacol ; 952: 175804, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37244377

RESUMO

Chronic stress affects millions of people around the world, and it can trigger different behavioral disorders like nociceptive hypersensitivity and anxiety, among others. However, the mechanisms underlaying these chronic stress-induced behavioral disorders have not been yet elucidated. This study was designed to understand the role of high-mobility group box-1 (HMGB1) and toll-like receptor 4 (TLR4) in chronic stress-induced nociceptive hypersensitivity. Chronic restraint stress induced bilateral tactile allodynia, anxiety-like behaviors, phosphorylation of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (p38MAPK) and activation of spinal microglia. Moreover, chronic stress enhanced HMGB1 and TLR4 protein expression at the dorsal root ganglion, but not at the spinal cord. Intrathecal injection of HMGB1 or TLR4 antagonists reduced tactile allodynia and anxiety-like behaviors induced by chronic stress. Additionally, deletion of TLR4 diminished the establishment of chronic stress-induced tactile allodynia in male and female mice. Lastly, the antiallodynic effect of HMGB1 and TLR4 antagonists were similar in stressed male and female rats and mice. Our results suggest that chronic restraint stress induces nociceptive hypersensitivity, anxiety-like behaviors, and up-regulation of spinal HMGB1 and TLR4 expression. Blockade of HMGB1 and TLR4 reverses chronic restraint stress-induced nociceptive hypersensitivity and anxiety-like behaviors and restores altered HMGB1 and TLR4 expression. The antiallodynic effects of HMGB1 and TLR4 blockers in this model are sex independent. TLR4 could be a potential pharmacological target for the treatment of the nociceptive hypersensitivity associated with widespread chronic pain.


Assuntos
Proteína HMGB1 , Hiperalgesia , Animais , Feminino , Masculino , Camundongos , Ratos , Alarminas/metabolismo , Doença Crônica , Proteína HMGB1/metabolismo , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Hiperalgesia/metabolismo , Nociceptividade , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Medula Espinal , Receptor 4 Toll-Like/metabolismo
6.
Front Immunol ; 14: 1259879, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38439942

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic triggered an unprecedented concentration of economic and research efforts to generate knowledge at unequalled speed on deregulated interferon type I signalling and nuclear factor kappa light chain enhancer in B-cells (NF-κB)-driven interleukin (IL)-1ß, IL-6, IL-18 secretion causing cytokine storms. The translation of the knowledge on how the resulting systemic inflammation can lead to life-threatening complications into novel treatments and vaccine technologies is underway. Nevertheless, previously existing knowledge on the role of cytoplasmatic or circulating self-DNA as a pro-inflammatory damage-associated molecular pattern (DAMP) was largely ignored. Pathologies reported 'de novo' for patients infected with Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 to be outcomes of self-DNA-driven inflammation in fact had been linked earlier to self-DNA in different contexts, e.g., the infection with Human Immunodeficiency Virus (HIV)-1, sterile inflammation, and autoimmune diseases. I highlight particularly how synergies with other DAMPs can render immunogenic properties to normally non-immunogenic extracellular self-DNA, and I discuss the shared features of the gp41 unit of the HIV-1 envelope protein and the SARS-CoV 2 Spike protein that enable HIV-1 and SARS-CoV-2 to interact with cell or nuclear membranes, trigger syncytia formation, inflict damage to their host's DNA, and trigger inflammation - likely for their own benefit. These similarities motivate speculations that similar mechanisms to those driven by gp41 can explain how inflammatory self-DNA contributes to some of most frequent adverse events after vaccination with the BNT162b2 mRNA (Pfizer/BioNTech) or the mRNA-1273 (Moderna) vaccine, i.e., myocarditis, herpes zoster, rheumatoid arthritis, autoimmune nephritis or hepatitis, new-onset systemic lupus erythematosus, and flare-ups of psoriasis or lupus. The hope is to motivate a wider application of the lessons learned from the experiences with COVID-19 and the new mRNA vaccines to combat future non-COVID-19 diseases.


Assuntos
COVID-19 , Ácidos Nucleicos Livres , Humanos , COVID-19/prevenção & controle , Vacina BNT162 , SARS-CoV-2 , Inflamação , Vacinação , Alarminas
7.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38203628

RESUMO

Psittacanthus calyculatus parasitizes mesquite trees through a specialized structure called a haustorium, which, in the intrusive process, can cause cellular damage in the host tree and release DAMPs, such as ATP, sugars, RNA, and DNA. These are highly conserved molecules that primarily function as signals that trigger and activate the defense responses. In the present study, we generate extracellular DNA (exDNA) from mesquite (P. laevigata) tree leaves (self-exDNA) and P. calyculatus (non-self exDNA) mistletoe as DAMP sources to examine mesquite trees' capacity to identify specific self or non-self exDNA. We determined that mesquite trees perceive self- and non-self exDNA with the synthesis of O2•-, H2O2, flavonoids, ROS-enzymes system, MAPKs activation, spatial concentrations of JA, SA, ABA, and CKs, and auxins. Our data indicate that self and non-self exDNA application differs in oxidative burst, JA signaling, MAPK gene expression, and scavenger systems. This is the first study to examine the molecular biochemistry effects in a host tree using exDNA sources derived from a mistletoe.


Assuntos
Erva-de-Passarinho , Prosopis , Alarminas , DNA , Peróxido de Hidrogênio , Árvores
8.
Front Immunol ; 13: 941757, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439184

RESUMO

Purpose: Some first-line cytotoxic chemotherapics, e.g. doxorubicin, paclitaxel and oxaliplatin, induce activation of the immune system through immunogenic cell death (ICD). Tumor cells undergoing ICD function as a vaccine, releasing damage-associated molecular patterns (DAMPs), which act as adjuvants, and neoantigens of the tumor are recognized as antigens. ICD induction is rare, however it yields better and long-lasting antitumor responses to chemotherapy. Advanced metastatic melanoma (AMM) is incurable for more than half of patients. The discovery of ICD inducers against AMM is an interesting drug discovery strategy with high translational potential. Here we evaluated ICD induction of four highly cytotoxic chromomycins A (CA5-8). Methods: ICD features and DAMPs were evaluated using several in vitro techniques with metastatic melanoma cell line (B16-F10) exposed to chromomcins A5-8 such as flow cytometry, western blot, RT-PCR and luminescence. Additionally in vivo vaccination assays with CA5-treated cells in a syngeneic murine model (C57Bl/6) were performed to confirm ICD evaluating the immune cells activation and their antitumor activity. Results: B16-F10 treated with CA5-8 and doxorubicin exhibited ICD features such as autophagy and apoptosis, externalization of calreticulin, and releasing of HMGB1. However, CA5-treated cells had the best profile, also inducing ATP release, ERp57 externalization, phosphorylation of eIF2α and altering expression of transcription of genes related to autophagy, endoplasmic reticulum stress, and apoptosis. Bona fide ICD induction by CA5 was confirmed by vaccination of C57BL/6 mice with CA5-treated cells which activated antigen-presenting cells and T lymphocytes and stimulated antitumor activity. Conclusion: CA5 induces bona fide immunogenic cell death on melanoma.


Assuntos
Antineoplásicos , Melanoma , Camundongos , Animais , Morte Celular Imunogênica , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Melanoma/tratamento farmacológico , Doxorrubicina , Alarminas , Linfócitos T
9.
J Neuroimmunol ; 371: 577951, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35994946

RESUMO

Depression is a heterogeneous mental disorder characterized by feelings of sadness and loss of interest that render the subject unable to handle basic daily activities such as sleeping, eating, or working. Neurobiological traits leading to depression include genetic background, early life abuse, life stressors, and systemic and central inflammatory profiles. Several clinical and preclinical reports documented that depression shows an increase in pro-inflammatory markers such as interleukin (IL-)1ß, IL-6, IL-12, tumor necrosis factor (TNF), and interferon (IFN)-γ; and a decrease in anti-inflammatory IL-4, IL-10, and transforming growth factor (TGF)-ß species. Inflammatory activation may trigger and maintain depression. Dynamic crosstalk between the peripheral immune system and the central nervous system (CNS) such as activated endothelial cells, monocytes, monocyte-derived dendritic cells, macrophages, T cells, and microglia has been proposed as a leading cause of neuroinflammation. Notably, pro-inflammatory cytokines disrupt the hypothalamic-pituitary-adrenal (HPA) axis and serotonergic, noradrenergic, dopaminergic, and glutamatergic neurotransmission. While still under investigation, peripheral cytokines can engage brain pathways and affect the central synthesis of HPA hormones and neurotransmitters through several mechanisms such as activation of the vagus nerve, increasing the permeability of the blood-brain barrier (BBB), altered cytokines transport systems, and engaging toll-like receptors (TLRs) by pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs). However, physiological mechanisms that favor time-dependent central inflammation before or during illness are not totally understood. This review will provide preclinical and clinical evidence of DAMPs and the BBB permeability as contributors to depression and neuroinflammation. We will also discuss pharmacologic approaches that could potentially modulate DAMPs and BBB permeability for future interventions against major depression.


Assuntos
Alarminas , Barreira Hematoencefálica , Barreira Hematoencefálica/patologia , Citocinas/metabolismo , Depressão , Células Endoteliais/metabolismo , Humanos , Doenças Neuroinflamatórias , Permeabilidade
10.
Biomolecules ; 11(11)2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34827548

RESUMO

SARS-CoV-2 contains certain molecules that are related to the presence of immunothrombosis. Here, we review the pathogen and damage-associated molecular patterns. We also study the imbalance of different molecules participating in immunothrombosis, such as tissue factor, factors of the contact system, histones, and the role of cells, such as endothelial cells, platelets, and neutrophil extracellular traps. Regarding the pathogenetic mechanism, we discuss clinical trials, case-control studies, comparative and translational studies, and observational studies of regulatory or inhibitory molecules, more specifically, extracellular DNA and RNA, histones, sensors for RNA and DNA, as well as heparin and heparinoids. Overall, it appears that a network of cells and molecules identified in this axis is simultaneously but differentially affecting patients at different stages of COVID-19, and this is characterized by endothelial damage, microthrombosis, and inflammation.


Assuntos
Alarminas , COVID-19/virologia , SARS-CoV-2 , Tromboinflamação/virologia , Trombose/virologia , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Coagulação Sanguínea , Plaquetas/virologia , COVID-19/complicações , DNA/metabolismo , Armadilhas Extracelulares , Heparina/metabolismo , Histonas/metabolismo , Humanos , Camundongos , Neuropilina-1/metabolismo , RNA/metabolismo , Transdução de Sinais , Trombina/metabolismo , Tromboplastina/metabolismo , Trombose/complicações
11.
Immunology ; 163(4): 377-388, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34042182

RESUMO

Apoptosis-associated speck-like protein containing a caspase recruit domain (ASC), encoded by PYCARD gene, is a 22 kDa small molecule, which aggregates into ASC specks during inflammasome activation. ASC protein is an adaptor protein present in several inflammasome complexes that performs several intra- and extracellular functions, in monomeric form or as ASC specks, during physiological and pathological processes related to inflammation and adaptive immunity. Extracellular ASC specks (eASC specks) released during cell death by pyroptosis can contribute as a danger signal to the propagation of inflammation via phagocytosis and activation of surrounding cells. ASC specks are found in the circulation of patients with chronic inflammatory diseases and have been considered as relevant blood biomarkers of inflammation. eASC amplifies the inflammatory signal, may induce the production of autoantibodies, transports molecules that bind to this complex, contributing to the generation of antibodies, and can induce the maturation of cytokines promoting the modelling of the adaptive immunity. Although several advances have been registered in the last 21 years, there are numerous unknown or enigmatic gaps in the understanding of the role of eASC specks in the organism. Here, we provide an overview about the ASC protein focusing on the probable roles of eASC specks in several diseases, up to the most recent studies concerning COVID-19.


Assuntos
Imunidade Adaptativa , Alarminas/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Inflamassomos/metabolismo , Mediadores da Inflamação/metabolismo , Inflamação/metabolismo , Animais , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/patologia , COVID-19/virologia , Interações Hospedeiro-Patógeno , Humanos , Inflamassomos/imunologia , Inflamação/imunologia , Inflamação/patologia , Fagocitose , Piroptose , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Transdução de Sinais
12.
Front Immunol ; 12: 624919, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33796100

RESUMO

Neuroinflammatory and neurodegenerative diseases are a major public health problem worldwide, especially with the increase of life-expectancy observed during the last decades. For many of these diseases, we still lack a full understanding of their etiology and pathophysiology. Nonetheless their association with mitochondrial dysfunction highlights this organelle as an important player during CNS homeostasis and disease. Markers of Parkinson (PD) and Alzheimer (AD) diseases are able to induce innate immune pathways induced by alterations in mitochondrial Ca2+ homeostasis leading to neuroinflammation. Additionally, exacerbated type I IFN responses triggered by mitochondrial DNA (mtDNA), failures in mitophagy, ER-mitochondria communication and mtROS production promote neurodegeneration. On the other hand, regulation of mitochondrial dynamics is essential for CNS health maintenance and leading to the induction of IL-10 and reduction of TNF-α secretion, increased cell viability and diminished cell injury in addition to reduced oxidative stress. Thus, although previously solely seen as power suppliers to organelles and molecular processes, it is now well established that mitochondria have many other important roles, including during immune responses. Here, we discuss the importance of these mitochondrial dynamics during neuroinflammation, and how they correlate either with the amelioration or worsening of CNS disease.


Assuntos
Encéfalo/metabolismo , Inflamação/metabolismo , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Doenças Neurodegenerativas/metabolismo , Neuroimunomodulação , Alarminas/metabolismo , Animais , Encéfalo/imunologia , Encéfalo/patologia , Citocinas/metabolismo , Humanos , Inflamação/imunologia , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Mitocôndrias/imunologia , Mitocôndrias/patologia , Degeneração Neural , Doenças Neurodegenerativas/imunologia , Doenças Neurodegenerativas/patologia
13.
Immunotherapy ; 13(4): 309-326, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33397152

RESUMO

Aim: Whole dead tumor cells can be used as antigen source and the induction of protective immune response could be enhanced by damage-associated molecular patterns. Materials & methods: We generated whole dead tumor cells called B16-immunogenic cell bodies (ICBs) from B16 melanoma cells by nutrient starvation and evaluated the in vivo antitumor effect of B16-ICBs plus ATP and polymyxin B (PMB). Results: The subcutaneous immunization with B16-ICBs + PMB + ATP a 50% of tumor-free animals and induced a significant delay in tumor growth in a prophylactic approach. These results correlated with maturation of bone marrow-derived dendritic cells and activation of T CD8+ lymphocytes in vitro. Conclusion: Altogether, ICB + ATP + PMB is efficient in inducing the antitumor efficacy of the whole dead tumor cells vaccine.


Assuntos
Trifosfato de Adenosina/imunologia , Vacinas Anticâncer/imunologia , Melanoma Experimental/imunologia , Polimixina B/imunologia , Trifosfato de Adenosina/administração & dosagem , Alarminas/administração & dosagem , Alarminas/imunologia , Animais , Apresentação de Antígeno , Antígenos de Neoplasias/imunologia , Antígenos CD40/metabolismo , Vacinas Anticâncer/administração & dosagem , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Imunização , Melanoma Experimental/patologia , Melanoma Experimental/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Fagocitose , Polimixina B/administração & dosagem , Baço/imunologia , Células Tumorais Cultivadas
15.
Front Immunol ; 11: 581445, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133101

RESUMO

Initially described as Th2 promoter cytokine, more recently, IL-33 has been recognized as an alarmin, mainly in epithelial and endothelial cells. While localized in the nucleus acting as a gene regulator, it can be also released after injury, stress or inflammatory cell death. As proinflammatory signal, IL-33 binds to the surface receptor ST2, which enhances mast cell, Th2, regulatory T cell, and innate lymphoid cell type 2 functions. Besides these Th2 roles, free IL-33 can activate CD8+ T cells during ongoing Th1 immune responses to potentiate its cytotoxic function. Celiac Disease (CD) is a chronic inflammatory disorder characterized by a predominant Th1 response leading to multiple pathways of mucosal damage in the proximal small intestine. By immunofluorescence and western blot analysis of duodenal tissues, we found an increased expression of IL-33 in duodenal mucosa of active CD (ACD) patients. Particularly, locally digested IL-33 releases active 18/21kDa fragments which can contribute to expand the proinflammatory signal. Endothelial (CD31+) and mesenchymal, myofibroblast and pericyte cells from microvascular structures in villi and crypts, showed IL-33 nuclear location; while B cells (CD20+) showed a strong cytoplasmic staining. Both ST2 forms, ST2L and sST2, were also upregulated in duodenal mucosa of CD patients. This was accompanied by increased number of CD8+ST2+ T cells and the expression of T-bet in some ST2+ intraepithelial lymphocytes and lamina propria cells. IL-33 and sST2 mRNA levels correlated with IRF1, an IFN induced factor relevant in responses to viral infections and interferon mediated proinflammatory responses highly represented in duodenal tissues in ACD. These findings highlight the potential contribution of IL-33 and its fragments to exacerbate the proinflammatory circuit and potentiate the cytotoxic activity of CD8+ T cells in CD pathology.


Assuntos
Alarminas/imunologia , Doença Celíaca/imunologia , Inflamação/imunologia , Interleucina-33/imunologia , Intestino Delgado/imunologia , Animais , Linfócitos B/imunologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Citocinas/imunologia , Células HT29 , Humanos , Proteína 1 Semelhante a Receptor de Interleucina-1/imunologia , Mucosa Intestinal/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/imunologia , Células Th2/imunologia
16.
Front Immunol ; 11: 1822, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983090

RESUMO

Innate immunity is one of the main protection mechanisms against viral infections, but how this system works at the maternal-fetal interface, especially during HIV infection, is still poorly known. In this study, we investigated the relationship between pregnancy and innate mechanisms associated with HIV immunity by evaluating the expression of DAMPs, inflammasome components and type I/III IFNs in placenta and serum samples from HIV-infected mothers and exposed newborns. Our results showed that most of these factors, including HMGB1, IL-1, and IFN, were increased in placental villi from HIV-infected mothers. Curiously, however, these factors were simultaneously repressed in serum from HIV-infected mothers and their exposed newborns, suggesting that pregnancy could restrict HIV immune activation systemically but preserve the immune response at the placental level. An effective local antiviral status associated with a suppressed inflammatory environment can balance the maternal immune response, promoting homeostasis for fetal development and protection against HIV infection in neonates.


Assuntos
Alarminas/metabolismo , Infecções por HIV/imunologia , HIV/imunologia , Imunidade Inata , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Mediadores da Inflamação/metabolismo , Placenta/imunologia , Adolescente , Adulto , Alarminas/genética , Brasil , Feminino , Sangue Fetal/imunologia , Sangue Fetal/virologia , HIV/patogenicidade , Infecções por HIV/diagnóstico , Infecções por HIV/virologia , Proteína HMGB1/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Recém-Nascido , Interferons/metabolismo , Interleucina-1/metabolismo , Mães , Placenta/metabolismo , Placenta/virologia , Gravidez , Regulação para Cima , Adulto Jovem
17.
Front Immunol ; 11: 1323, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695110

RESUMO

Damage associated molecular patterns (DAMPs) are endogenous molecules originate from damaged cells and tissues with the ability to trigger and/or modify innate immune responses. Upon hemolysis hemoglobin (Hb) is released from red blood cells (RBCs) to the circulation and give a rise to the production of different Hb redox states and heme which can act as DAMPs. Heme is the best characterized Hb-derived DAMP that targets different immune and non-immune cells. Heme is a chemoattractant, activates the complement system, modulates host defense mechanisms through the activation of innate immune receptors and the heme oxygenase-1/ferritin system, and induces innate immune memory. The contribution of oxidized Hb forms is much less studied, but some evidence show that these species might play distinct roles in intravascular hemolysis-associated pathologies independently of heme release. This review aims to summarize our current knowledge about the formation and pro-inflammatory actions of heme and other Hb-derived DAMPs.


Assuntos
Alarminas/imunologia , Heme/imunologia , Hemoglobinas/imunologia , Animais , Eritrócitos/imunologia , Humanos , Imunidade Inata
18.
BMC Cancer ; 20(1): 647, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32660440

RESUMO

BACKGROUND: IMMUNEPOTENT CRP (ICRP) can be cytotoxic to cancer cell lines. However, its widespread use in cancer patients has been limited by the absence of conclusive data on the molecular mechanism of its action. Here, we evaluated the mechanism of cell death induced by ICRP in HeLa and MCF-7 cells. METHODS: Cell death, cell cycle, mitochondrial membrane potential and ROS production were evaluated in HeLa and MCF-7 cell lines after ICRP treatment. Caspase-dependence and ROS-dependence were evaluated using QVD.oph and NAC pre-treatment in cell death analysis. DAMPs release, ER stress (eIF2-α phosphorylation) and autophagosome formation were analyzed as well. Additionally, the role of autophagosomes in cell death induced by ICRP was evaluated using SP-1 pre-treatment in cell death in HeLa and MCF-7 cells. RESULTS: ICRP induces cell death, reaching CC50 at 1.25 U/mL and 1.5 U/mL in HeLa and MCF-7 cells, respectively. Loss of mitochondrial membrane potential, ROS production and cell cycle arrest were observed after ICRP CC50 treatment in both cell lines, inducing the same mechanism, a type of cell death independent of caspases, relying on ROS production. Additionally, ICRP-induced cell death involves features of immunogenic cell death such as P-eIF2α and CRT exposure, as well as, ATP and HMGB1 release. Furthermore, ICRP induces ROS-dependent autophagosome formation that acts as a pro-survival mechanism. CONCLUSIONS: ICRP induces a non-apoptotic cell death that requires an oxidative stress to take place, involving mitochondrial damage, ROS-dependent autophagosome formation, ER stress and DAMPs' release. These data indicate that ICRP could work together with classic apoptotic inductors to attack cancer cells from different mechanisms, and that ICRP-induced cell death might activate an immune response against cancer cells.


Assuntos
Alarminas/metabolismo , Antineoplásicos/farmacologia , Autofagossomos , Neoplasias/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Fator de Transferência/administração & dosagem , Animais , Apoptose , Bovinos , Ciclo Celular , Proliferação de Células , Células HeLa , Humanos , Células MCF-7 , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neoplasias/patologia , Estresse Oxidativo
19.
BMC Cancer ; 20(1): 474, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32456685

RESUMO

BACKGROUND: Chemotherapeutics can stimulate immune antitumor response by inducing immunogenic cell death (ICD), which is activated by Damage-Associated Molecular Patterns (DAMPs) like the exposure of calreticulin (CRT) on the cell surface, the release of ATP and the secretion of High Mobility Group Box 1 (HMGB1). METHODS: Here, we investigated the levels of ICD-associated DAMPs induced by chemotherapeutics commonly used in the clinical practice of non-small cell lung cancer (NSCLC) and the association of these DAMPs with apoptosis and autophagy. A549 human lung adenocarcinoma cells were treated with clinically relevant doses of cisplatin, carboplatin, etoposide, paclitaxel and gemcitabine. We assessed ICD-associated DAMPs, cell viability, apoptosis and autophagy in an integrated way. RESULTS: Cisplatin and its combination with etoposide induced the highest levels of apoptosis, while etoposide was the less pro-apoptotic treatment. Cisplatin also induced the highest levels of ICD-associated DAMPs, which was not incremented by co-treatments. Etoposide induced the lower levels of ICD and the highest levels of autophagy, suggesting that the cytoprotective role of autophagy is dominant in relation to its pro-ICD role. High levels of CRT were associated with better prognosis in TCGA databank. In an integrative analysis we found a strong positive correlation between DAMPs and apoptosis, and a negative correlation between cell number and ICD-associated DAMPs as well as between autophagy and apoptosis markers. We also purpose a mathematical integration of ICD-associated DAMPs in an index (IndImunnog) that may represent with greater biological relevance this process. Cisplatin-treated cells showed the highest IndImmunog, while etoposide was the less immunogenic and the more pro-autophagic treatment. CONCLUSIONS: Cisplatin alone induced the highest levels of ICD-associated DAMPs, so that its combination with immunotherapy may be a promising therapeutic strategy in NSCLC.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Alarminas/metabolismo , Antineoplásicos/farmacologia , Morte Celular Imunogênica , Neoplasias Pulmonares/metabolismo , Células A549 , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/mortalidade , Adenocarcinoma de Pulmão/patologia , Trifosfato de Adenosina/metabolismo , Alarminas/efeitos dos fármacos , Apoptose , Autofagia , Calreticulina/metabolismo , Carboplatina/farmacologia , Caspase 3/metabolismo , Sobrevivência Celular , Cisplatino/farmacologia , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Etoposídeo/farmacologia , Proteína HMGB1/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Paclitaxel/farmacologia , Prognóstico , Gencitabina
20.
Transplantation ; 104(9): e252-e259, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32217944

RESUMO

BACKGROUND: Despite the benefits of ex vivo lung perfusion (EVLP) such as lung reconditioning, preservation, and evaluation before transplantation, deleterious effects, including activation of proinflammatory cascades and alteration of metabolic profiles have been reported. Although patient outcomes have been favorable, further studies addressing optimal conditions are warranted. In this study, we investigated the role of the immunosuppressant drug cyclosporine A (CyA) in preserving mitochondrial function and subsequently preventing proinflammatory changes in lung grafts during EVLP. METHODS: Using rat heart-lung blocks after 1-hour cold preservation, an acellular normothermic EVLP system was established for 4 hours. CyA was added into perfusate at a final concentration of 1 µM. The evaluation included lung graft function, lung compliance, and pulmonary vascular resistance as well as biochemical marker measurement in the perfusate at multiple time points. After EVLP, single orthotopic lung transplantation was performed, and the grafts were assessed 2 hours after reperfusion. RESULTS: Lung grafts on EVLP with CyA exhibited significantly better functional and physiological parameters as compared with those without CyA treatment. CyA administration attenuated proinflammatory changes and prohibited glucose consumption during EVLP through mitigating mitochondrial dysfunction in lung grafts. CyA-preconditioned lungs showed better posttransplant lung early graft function and less inflammatory events compared with control. CONCLUSIONS: During EVLP, CyA administration can have a preconditioning effect through both its anti-inflammatory and mitochondrial protective properties, leading to improved lung graft preservation, which may result in enhanced graft quality after transplantation.


Assuntos
Ciclosporina/farmacologia , Imunossupressores/farmacologia , Transplante de Pulmão/métodos , Pulmão/irrigação sanguínea , Alarminas/antagonistas & inibidores , Animais , Cálcio/metabolismo , Nucleotídeos de Desoxiadenina , Masculino , Perfusão , Ratos , Ratos Endogâmicos Lew , Condicionamento Pré-Transplante
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