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1.
Cell ; 156(3): 456-68, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24485454

RESUMO

The phagocytes of the innate immune system, macrophages and neutrophils, contribute to antibacterial defense, but their functional specialization and cooperation is unclear. Here, we report that three distinct phagocyte subsets play highly coordinated roles in bacterial urinary tract infection. Ly6C(-) macrophages acted as tissue-resident sentinels that attracted circulating neutrophils and Ly6C(+) macrophages. Such Ly6C(+) macrophages played a previously undescribed helper role: once recruited to the site of infection, they produced the cytokine TNF, which caused Ly6C(-) macrophages to secrete CXCL2. This chemokine activated matrix metalloproteinase-9 in neutrophils, allowing their entry into the uroepithelium to combat the bacteria. In summary, the sentinel macrophages elicit the powerful antibacterial functions of neutrophils only after confirmation by the helper macrophages, reminiscent of the licensing role of helper T cells in antiviral adaptive immunity. These findings identify helper macrophages and TNF as critical regulators in innate immunity against bacterial infections in epithelia.


Assuntos
Infecções Bacterianas/imunologia , Macrófagos/imunologia , Neutrófilos/imunologia , Infecções Urinárias/imunologia , Animais , Antígenos Ly/metabolismo , Quimiocina CXCL2/imunologia , Feminino , Doenças do Sistema Imunitário , Cinética , Transtornos Leucocíticos , Macrófagos/citologia , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Neutrófilos/citologia , Organismos Livres de Patógenos Específicos , Fator de Necrose Tumoral alfa/imunologia
2.
Nature ; 590(7845): 320-325, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33260195

RESUMO

The expanding pandemic of coronavirus disease 2019 (COVID-19) requires the development of safe, efficacious and fast-acting vaccines. Several vaccine platforms are being leveraged for a rapid emergency response1. Here we describe the development of a candidate vaccine (YF-S0) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that uses live-attenuated yellow fever 17D (YF17D) vaccine as a vector to express a noncleavable prefusion form of the SARS-CoV-2 spike antigen. We assess vaccine safety, immunogenicity and efficacy in several animal models. YF-S0 has an excellent safety profile and induces high levels of SARS-CoV-2 neutralizing antibodies in hamsters (Mesocricetus auratus), mice (Mus musculus) and cynomolgus macaques (Macaca fascicularis), and-concomitantly-protective immunity against yellow fever virus. Humoral immunity is complemented by a cellular immune response with favourable T helper 1 polarization, as profiled in mice. In a hamster model2 and in macaques, YF-S0 prevents infection with SARS-CoV-2. Moreover, a single dose conferred protection from lung disease in most of the vaccinated hamsters within as little as 10 days. Taken together, the quality of the immune responses triggered and the rapid kinetics by which protective immunity can be attained after a single dose warrant further development of this potent SARS-CoV-2 vaccine candidate.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Vetores Genéticos/genética , SARS-CoV-2/imunologia , Vacinas Atenuadas/imunologia , Vacina contra Febre Amarela/genética , Animais , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/genética , Cricetinae , Modelos Animais de Doenças , Feminino , Glicosilação , Macaca fascicularis/genética , Macaca fascicularis/imunologia , Macaca fascicularis/virologia , Masculino , Mesocricetus/genética , Mesocricetus/imunologia , Mesocricetus/virologia , Camundongos , Segurança , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/genética
3.
Med Res Rev ; 43(5): 1537-1606, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37036061

RESUMO

Neutrophils are powerful effector cells leading the first wave of acute host-protective responses. These innate leukocytes are endowed with oxidative and nonoxidative defence mechanisms, and play well-established roles in fighting invading pathogens. With microbicidal weaponry largely devoid of specificity and an all-too-well recognized toxicity potential, collateral damage may occur in neutrophil-rich diseases. However, emerging evidence suggests that neutrophils are more versatile, heterogeneous, and sophisticated cells than initially thought. At the crossroads of innate and adaptive immunity, neutrophils demonstrate their multifaceted functions in infectious and noninfectious pathologies including cancer, autoinflammation, and autoimmune diseases. Here, we discuss the kinetics of neutrophils and their products of activation from bench to bedside during health and disease, and provide an overview of the versatile functions of neutrophils as key modulators of immune responses and physiological processes. We focus specifically on those activities and concepts that have been validated with primary human cells.


Assuntos
Anti-Infecciosos , Neoplasias , Humanos , Neutrófilos , Imunidade Inata , Imunidade Adaptativa , Inflamação
4.
Trends Immunol ; 41(5): 367-378, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32299652

RESUMO

Autoimmune diseases are defined as pathologies of adaptive immunity by the presence of autoantibodies or MHC-restricted autoantigen-reactive T cells. Because autoreactivity is a normal process based on mechanisms producing repertoires of antibodies and T cell receptors, crucial questions about disease mechanisms and key steps for interference have been outstanding. We defined 25 years ago the 'remnant epitopes generate autoimmunity' (REGA)-model in which extracellular proteases from innate immune cells generate autoantigens. Here, we refine the REGA-model, tested in diseases ranging from organ-specific autoimmune diseases to systemic lupus erythematosus. It now constitutes a paradigm in which remnant epitopes generate, maintain, and regulate autoimmunity; are dependent on genetic and epigenetic influences; are produced in a disease phase-specific manner; and have therapeutic implications when targeted.


Assuntos
Doenças Autoimunes , Lúpus Eritematoso Sistêmico , Humanos , Autoimunidade , Epitopos , Autoantígenos , Autoanticorpos
5.
Proc Natl Acad Sci U S A ; 117(9): 5028-5038, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32071226

RESUMO

The brain's endogenous capacity to restore damaged myelin deteriorates during the course of demyelinating disorders. Currently, no treatment options are available to establish remyelination. Chronic demyelination leads to damaged axons and irreversible destruction of the central nervous system (CNS). We identified two promising therapeutic candidates which enhance remyelination: oncostatin M (OSM), a member of the interleukin-6 family, and downstream mediator tissue inhibitor of metalloproteinases-1 (TIMP-1). While remyelination was completely abrogated in OSMRß knockout (KO) mice, OSM overexpression in the chronically demyelinated CNS established remyelination. Astrocytic TIMP-1 was demonstrated to play a pivotal role in OSM-mediated remyelination. Astrocyte-derived TIMP-1 drove differentiation of oligodendrocyte precursor cells into mature oligodendrocytes in vitro. In vivo, TIMP-1 deficiency completely abolished spontaneous remyelination, phenocopying OSMRß KO mice. Finally, TIMP-1 was expressed by human astrocytes in demyelinated multiple sclerosis lesions, confirming the human value of our findings. Taken together, OSM and its downstream mediator TIMP-1 have the therapeutic potential to boost remyelination in demyelinating disorders.


Assuntos
Astrócitos/metabolismo , Oncostatina M/metabolismo , Remielinização/fisiologia , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Animais , Astrócitos/patologia , Axônios , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Humanos , Interleucina-6/metabolismo , Camundongos , Camundongos Knockout , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Bainha de Mielina , Células Precursoras de Oligodendrócitos , Inibidor Tecidual de Metaloproteinase-1/genética
6.
Int J Mol Sci ; 24(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37686317

RESUMO

Inflammation and fibrosis are key features of proliferative vitreoretinal disorders. We aimed to define the macrophage phenotype and investigate the role of macrophage-myofibroblast transition (MMT) in the contribution to myofibroblast populations present in epiretinal membranes. Vitreous samples from proliferative diabetic retinopathy (PDR), proliferative vitreoretinopathy (PVR) and nondiabetic control patients, epiretinal fibrovascular membranes from PDR patients and fibrocellular membranes from PVR patients, human retinal Müller glial cells and human retinal microvascular endothelial cells (HRMECs) were studied by ELISA, immunohistochemistry and flow cytometry analysis. Myofibroblasts expressing α-SMA, fibroblast activation protein-α (FAP-α) and fibroblast-specific protein-1 (FSP-1) were present in all membranes. The majority of CD68+ monocytes/macrophages co-expressed the M2 macrophage marker CD206. In epiretinal membranes, cells undergoing MMT were identified by co-expression of the macrophage marker CD68 and myofibroblast markers α-SMA and FSP-1. Further analysis revealed that CD206+ M2 macrophages co-expressed α-SMA, FSP-1, FAP-α and ß-catenin. Soluble (s) CD206 and sFAP-α levels were significantly higher in vitreous samples from PDR and PVR patients than in nondiabetic control patients. The proinflammatory cytokine TNF-α and the hypoxia mimetic agent cobalt chloride induced upregulation of sFAP-α in culture media of Müller cells but not of HRMECs. The NF-Ä¸ß inhibitor BAY11-7085 significantly attenuated TNF-α-induced upregulation of sFAP-α in Müller cells. Our findings suggest that the process of MMT might contribute to myofibroblast formation in epiretinal membranes, and this transition involved macrophages with a predominant M2 phenotype. In addition, sFAP-α as a vitreous biomarker may be derived from M2 macrophages transitioned to myofibroblasts and from Müller cells.


Assuntos
Retinopatia Diabética , Membrana Epirretiniana , Oftalmopatias , Vitreorretinopatia Proliferativa , Humanos , Células Endoteliais , Miofibroblastos , Fator de Necrose Tumoral alfa
7.
Int J Mol Sci ; 24(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37958563

RESUMO

We aimed to investigate the role of the CD40-CD40 ligand (CD40L) pathway in inflammation-mediated angiogenesis in proliferative diabetic retinopathy (PDR). We analyzed vitreous fluids and epiretinal fibrovascular membranes from PDR and nondiabetic patients, cultures of human retinal microvascular endothelial cells (HRMECs) and Müller glial cells and rat retinas with ELISA, immunohistochemistry, flow cytometry and Western blot analysis. Functional tests included measurement of blood-retinal barrier breakdown, in vitro angiogenesis and assessment of monocyte-HRMEC adherence. CD40L and CD40 levels were significantly increased in PDR vitreous samples. We demonstrated CD40L and CD40 expression in vascular endothelial cells, leukocytes and myofibroblasts in epiretinal membranes. Intravitreal administration of soluble (s)CD40L in normal rats significantly increased retinal vascular permeability and induced significant upregulation of phospho-ERK1/2, VEGF, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). sCD40L induced upregulation of VEGF, MMP-9, MCP-1 and HMGB1 in cultured Müller cells and phospo-ERK1/2, p65 subunit of NF-ĸB, VCAM-1 and VEGF in cultured HRMECS. TNF-α induced significant upregulation of CD40 in HRMECs and Müller cells and VEGF induced significant upregulation of CD40 in HRMECs. sCD40L induced proliferation and migration of HRMECs. We provide experimental evidence supporting the involvement of the CD40L-CD40 pathway and how it regulates inflammatory angiogenesis in PDR.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Ratos , Animais , Retinopatia Diabética/metabolismo , Ligante de CD40/metabolismo , Células Endoteliais/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ratos Sprague-Dawley , Inflamação/metabolismo , Diabetes Mellitus/metabolismo
8.
Crit Rev Biochem Mol Biol ; 55(2): 111-165, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32290726

RESUMO

Proteases are a diverse group of hydrolytic enzymes, ranging from single-domain catalytic molecules to sophisticated multi-functional macromolecules. Human proteases are divided into five mechanistic classes: aspartate, cysteine, metallo, serine and threonine proteases, based on the catalytic mechanism of hydrolysis. As a protective mechanism against uncontrolled proteolysis, proteases are often produced and secreted as inactive precursors, called zymogens, containing inhibitory N-terminal propeptides. Protease propeptide structures vary considerably in length, ranging from dipeptides and propeptides of about 10 amino acids to complex multifunctional prodomains with hundreds of residues. Interestingly, sequence analysis of the different protease domains has demonstrated that propeptide sequences present higher heterogeneity compared with their catalytic domains. Therefore, we suggest that protease inhibition targeting propeptides might be more specific and have less off-target effects than classical inhibitors. The roles of propeptides, besides keeping protease latency, include correct folding of proteases, compartmentalization, liganding, and functional modulation. Changes in the propeptide sequence, thus, have a tremendous impact on the cognate enzymes. Small modifications of the propeptide sequences modulate the activity of the enzymes, which may be useful as a therapeutic strategy. This review provides an overview of known human proteases, with a focus on the role of their propeptides. We review propeptide functions, activation mechanisms, and possible therapeutic applications.


Assuntos
Precursores Enzimáticos/química , Precursores Enzimáticos/metabolismo , Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Sequência de Aminoácidos , Biomarcadores/química , Biomarcadores/metabolismo , Domínio Catalítico , Ativação Enzimática , Precursores Enzimáticos/classificação , Precursores Enzimáticos/genética , Humanos , Mutação , Peptídeo Hidrolases/classificação , Peptídeo Hidrolases/genética , Dobramento de Proteína , Multimerização Proteica , Proteólise
9.
Clin Exp Ophthalmol ; 50(6): 632-652, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35322530

RESUMO

BACKGROUND: Furin converts inactive proproteins into bioactive forms. By activating proinflammatory and proangiogenic factors, furin might play a role in pathophysiology of proliferative diabetic retinopathy (PDR). METHODS: We studied vitreous samples from PDR and nondiabetic patients, epiretinal membranes from PDR patients, retinal microvascular endothelial cells (HRMECs), retinal Müller cells and rat retinas by ELISA, Western blot analysis, immunohistochemistry and immunofluorescence microscopy. We performed in vitro angiogenesis assays and assessed adherence of monocytes to HRMECs. RESULTS: Furin levels were significantly increased in PDR vitreous samples. In epiretinal membranes, immunohistochemistry analysis revealed furin expression in monocytes/macrophages, vascular endothelial cells and myofibroblasts. Furin was significantly upregulated in diabetic rat retinas. Hypoxia and TNF-α induced significant upregulation of furin in Müller cells and HRMECs. Furin induced upregulation of phospho-ERK1/2, p65 subunit of NF-κB, ADAM17 and MCP-1 in cultured Müller cells and phospho-ERK1/2 in cultured HRMECs and induced HRMECs migration. Treatment of monocytes with furin significantly increased their adhesion to HRMECs. Intravitreal administration of furin in normal rats induced significant upregulation of p65 subunit of NF-κB, phospho-ERK1/2 and ICAM-1 in the retina. Inhibition of furin with dec-CMK significantly decreased levels of MCP-1 in culture medium of Müller cells and HRMECs and significantly attenuated TNF-α-induced upregulation of p65 subunit of NF-κB, ICAM-1 and VCAM-1 in HRMECs. Dec-CMK significantly decreased adherence of monocytes to HRMECs and TNF-α-induced upregulation of adherence of monocytes to HRMECs. Treatment of HRMECs with dec-CMK significantly attenuated migration of HRMECs. CONCLUSIONS: Furin is a potential driver molecule of PDR-associated inflammation and angiogenesis.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Membrana Epirretiniana , Furina , Animais , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/metabolismo , Células Endoteliais/metabolismo , Furina/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , NF-kappa B/metabolismo , Neovascularização Patológica/metabolismo , Pró-Proteína Convertases/metabolismo , Ratos , Fator de Necrose Tumoral alfa/metabolismo , Corpo Vítreo/metabolismo
10.
Molecules ; 27(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36144730

RESUMO

We analyzed the expression of ADAMTS proteinases ADAMTS-1, -2, -4, -5 and -13; their activating enzyme MMP-15; and the degradation products of proteoglycan substrates versican and biglycan in an ocular microenvironment of proliferative diabetic retinopathy (PDR) patients. Vitreous samples from PDR and nondiabetic patients, epiretinal fibrovascular membranes from PDR patients, rat retinas, retinal Müller glial cells and human retinal microvascular endothelial cells (HRMECs) were studied. The levels of ADAMTS proteinases and MMP-15 were increased in the vitreous from PDR patients. Both full-length and cleaved activation/degradation fragments of ADAMTS proteinases were identified. The amounts of versican and biglycan cleavage products were increased in vitreous from PDR patients. ADAMTS proteinases and MMP-15 were localized in endothelial cells, monocytes/macrophages and myofibroblasts in PDR membranes, and ADAMTS-4 was expressed in the highest number of stromal cells. The angiogenic activity of PDR membranes correlated significantly with levels of ADAMTS-1 and -4 cellular expression. ADAMTS proteinases and MMP-15 were expressed in rat retinas. ADAMTS-1 and -5 and MMP-15 levels were increased in diabetic rat retinas. HRMECs and Müller cells constitutively expressed ADAMTS proteinases but not MMP-15. The inhibition of NF-κB significantly attenuated the TNF-α-and-VEGF-induced upregulation of ADAMTS-1 and -4 in a culture medium of HRMECs and Müller cells. In conclusion, ADAMTS proteinases, MMP-15 and versican and biglycan cleavage products were increased in the ocular microenvironment of patients with PDR.


Assuntos
Proteínas ADAMTS/metabolismo , Diabetes Mellitus Experimental , Retinopatia Diabética , Animais , Biglicano/metabolismo , Western Blotting , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/metabolismo , Células Endoteliais/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , NF-kappa B/metabolismo , Peptídeo Hidrolases/metabolismo , Ratos , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Versicanas/genética , Versicanas/metabolismo , Corpo Vítreo/metabolismo
11.
Trends Immunol ; 39(4): 341-354, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29500031

RESUMO

Chronic skin wounds, caused by arterial or venous insufficiency or by physical pressure, constitute an increasing medical problem as populations age. Whereas typical wounds are characterized by local inflammation that participates in the healing process, atonic wounds lack inflammatory markers, such as neutrophil infiltration, and generally do not heal. Recently, prominent roles in the immunopathology of chronic wounds were attributed to dysregulations in specific cytokines, chemokines, matrix metalloproteinases (MMPs), and their substrates. Together with the complement system, these molecular players provide necessary defense against infections, initiate angiogenesis, and prepare tissue reconstitution. Here, we review the current state of the field and include the concept that, aside from surgery and stem cell therapy, healing may be enhanced by immunomodulating agents.


Assuntos
Dermatopatias/imunologia , Pele/patologia , Cicatrização , Animais , Doença Crônica , Proteínas do Sistema Complemento/metabolismo , Citocinas/metabolismo , Humanos , Imunomodulação , Metaloproteinases da Matriz
12.
Cell Mol Life Sci ; 77(15): 3013-3026, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31642940

RESUMO

Proteolysis is a crucial process in life, tightly controlled by numerous natural protease inhibitors. In human blood, alpha-2-macroglobulin is an emergency protease inhibitor preventing coagulation and damage to endothelia and leukocytes. With the use of a unique protease trapping mechanism, alpha-2-macroglobulin lures active proteases into its snap-trap, shields these from potential substrates and 'flags' their complex for elimination by receptor-mediated endocytosis. Matrix metalloprotease-9/gelatinase B is a secreted protease increased in blood of patients with inflammations, vascular disorders and cancers. Matrix metalloprotease-9 occurs as monomers and stable homotrimers, but the reason for their co-existence remains obscure. We discovered that matrix metalloprotease-9 homotrimers undergo reduced anti-proteolytic regulation by alpha-2-macroglobulin and are able to travel as a proteolytically active hitchhiker on alpha-2-macroglobulin. As a comparison, we revealed that monomeric active matrix metalloprotease-9 is efficiently trapped by human plasma alpha-2-macroglobulin and this masks the detection of activated matrix metalloprotease-9 with standard analysis techniques. In addition, we show that alpha-2-macroglobulin/trimer complexes escape clearance through the receptor low-density lipoprotein receptor-related protein 1, also known as the alpha-2-macroglobulin receptor. Thus, the biochemistry and biology of matrix metalloprotease-9 monomers and trimers are completely different as multimerization enables active matrix metalloprotease-9 to partially avoid alpha-2-macroglobulin regulation both by direct protease inhibition and by removal from the extracellular space by receptor-mediated endocytosis. Finally, for the biomarker field, the analysis of alpha-2-macroglobulin/protease complexes with upgraded technology is advocated as a quotum for protease activation in human plasma samples.


Assuntos
Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , alfa 2-Macroglobulinas Associadas à Gravidez/metabolismo , Linhagem Celular Tumoral , Endocitose , Humanos , Metaloproteinase 9 da Matriz/química , Metaloproteinase 9 da Matriz/genética , Mutagênese Sítio-Dirigida , Ligação Proteica , Multimerização Proteica , Proteólise
13.
Blood ; 131(4): 439-449, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29371208

RESUMO

A natural leukocyte chemoattractant was isolated from bovine serum by an established 4-step purification procedure. Based on its relative molecular mass of 7287 and NH2-terminal sequence, the protein was identified as a carboxy-terminal peptide of the acute phase protein serum amyloid A1 (SAA1). This SAA1(46-112) fragment and its human equivalent SAA1(47-104) were chemically synthesized. Unlike intact SAA1α, these SAA fragments failed to directly chemoattract neutrophils and monocytes, to induce chemokines, and to stimulate downstream extracellular signal-regulated kinase signaling in monocytes. However, the SAA fragments potently synergized with CCL3 to induce monocyte migration and with CXCL8 to stimulate neutrophil shape changes and chemotaxis. Unlike intact SAA1α, SAA1(46-112) did not induce CXCL6 ex vivo but provoked a cooperative intraperitoneal neutrophil recruitment in mice when coinjected with CXCL6 into the peritoneal cavity. Moreover, SAA1(47-104) desensitized the synergy between intact SAA1α and CXCL8 in neutrophil chemotaxis, suggesting that this peptide binds formyl peptide receptor 2 (FPR2). This was evidenced by a complete blockade of synergy between the COOH-terminal SAA1 fragments and CXCL8 or CCL3 in neutrophil and monocyte chemotaxis, respectively, by the FPR2 antagonist WRW4 Thus, SAA1 is degraded into fragments lacking chemokine-inducing capacity, while keeping synergy with cytokine-induced chemokines to sustain limited inflammation.


Assuntos
Quimiocina CCL3/imunologia , Quimiocinas/imunologia , Interleucina-8/imunologia , Leucócitos/efeitos dos fármacos , Receptores de Formil Peptídeo/imunologia , Receptores de Lipoxinas/imunologia , Proteína Amiloide A Sérica/química , Proteína Amiloide A Sérica/farmacologia , Animais , Bovinos , Quimiotaxia/efeitos dos fármacos , Feminino , Humanos , Leucócitos/imunologia , Camundongos , Peptídeos/síntese química , Peptídeos/química , Peptídeos/farmacologia , Proteína Amiloide A Sérica/síntese química
14.
Cell Mol Life Sci ; 76(16): 3157-3166, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31183508

RESUMO

Matrix metalloproteinases (MMPs) and related metalloproteinases with a disintegrin domain (ADAMs) have become interesting probes and targets in eye diseases, including diabetic retinopathy. We here summarize recent data about MMPs and ADAMs in retinopathies. Retinal diseases range from rare genetic afflictions to diabetic retinopathy, the latter of which is reaching epidemic proportions. MMPs and ADAMs play roles in normal eye development and in disease states, not only in local proteolysis but also signaling functions mediated by specific protein domains, interacting with cell surface receptors. In proliferative diabetic retinopathy, inflammation, hypoxia-induced vascular endothelial growth factor and oxidative stress collectively stimulate the production, activation and signaling functions of pro-MMP-9. This leads to angiogenesis, destruction of neuroprotective prominin-1, loss of photoreceptors and blood-retina barrier breakdown. Biological inhibition of proteolysis and control of signaling functions are executed by the tissue inhibitors of metalloproteases (TIMPs). Angiogenic, inflammatory and fibrotic reactions, in which MMPs, ADAMs and TIMPs are involved, co-determine common eye diseases. Therefore, visions about the use of these proteases as biomarkers and as targets for therapeutic inhibitors, including small molecule inhibitors and monoclonal antibodies, may lead to breakthroughs in tissue regeneration, maintenance of photoreceptors and neuroprotection.


Assuntos
Retinopatia Diabética/patologia , Metaloproteinases da Matriz/metabolismo , Doenças Vasculares/patologia , Antígeno AC133/metabolismo , Proteínas ADAM/metabolismo , Animais , Basigina/metabolismo , Retinopatia Diabética/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia , Inibidores Teciduais de Metaloproteinases/metabolismo , Doenças Vasculares/metabolismo
15.
Biochem J ; 476(15): 2191-2208, 2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31262730

RESUMO

Interleukin 2 (IL-2) is critical for T cell development and homeostasis, being a key regulator of adaptive immune responses in autoimmunity, hypersensitivity reactions and cancer. Therefore, its abundance in serum and peripheral tissues needs tight control. Here, we described a new mechanism contributing to the immunobiology of IL-2. We demonstrated, both in biochemical and cell-based assays, that IL-2 is subject to proteolytic processing by neutrophil matrix metalloproteinase-9 (MMP-9). IL-2 fragments produced after cleavage by MMP-9 remained linked by a disulfide bond and displayed a reduced affinity for all IL-2 receptor subunits and a distinct pattern and timing of signal transduction. Stimulation of IL-2-dependent cells, including murine CTLL-2 and primary human regulatory T cells, with cleaved IL-2 resulted in significantly decreased proliferation. The concerted action of neutrophil proteases destroyed IL-2. Our data suggest that in neutrophil-rich inflammatory conditions in vivo, neutrophil MMP-9 may reduce the abundance of signaling-competent IL-2 and generate a fragment that competes with IL-2 for receptor binding, whereas the combined activity of granulocyte proteases has the potential to degrade and thus eliminate bioavailable IL-2.


Assuntos
Interleucina-2/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Neutrófilos/enzimologia , Transdução de Sinais , Linfócitos T Reguladores/imunologia , Animais , Linhagem Celular , Humanos , Interleucina-2/genética , Metaloproteinase 9 da Matriz/genética , Camundongos
16.
Int J Mol Sci ; 21(12)2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32604901

RESUMO

Neutrophils are the most abundant circulating and first-responding innate myeloid cells and have so far been underestimated in the context of multiple sclerosis (MS). MS is the most frequent, immune-mediated, inflammatory disease of the central nervous system. MS is treatable but not curable and its cause(s) and pathogenesis remain elusive. The involvement of neutrophils in MS pathogenesis has been suggested by the use of preclinical animal disease models, as well as on the basis of patient sample analysis. In this review, we provide an overview of the possible mechanisms and functions by which neutrophils may contribute to the development and pathology of MS. Neutrophils display a broad variety of effector functions enabling disease pathogenesis, including (1) the release of inflammatory mediators and enzymes, such as interleukin-1ß, myeloperoxidase and various proteinases, (2) destruction and phagocytosis of myelin (as debris), (3) release of neutrophil extracellular traps, (4) production of reactive oxygen species, (5) breakdown of the blood-brain barrier and (6) generation and presentation of autoantigens. An important question relates to the issue of whether neutrophils exhibit a predominantly proinflammatory function or are also implicated in the resolution of chronic inflammatory responses in MS.


Assuntos
Imunidade Inata/imunologia , Mediadores da Inflamação/metabolismo , Esclerose Múltipla/patologia , Neutrófilos/patologia , Fagocitose , Espécies Reativas de Oxigênio/metabolismo , Animais , Humanos , Esclerose Múltipla/imunologia , Esclerose Múltipla/metabolismo , Neutrófilos/imunologia
17.
J Cell Mol Med ; 23(1): 576-585, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30358100

RESUMO

Gelatin zymography analysis is a sensitive method and commonly used to characterize and quantify the presence of the gelatinases (MMP-2 and MMP-9) in biological samples. In human plasma samples from healthy controls and systemic lupus erythematosus (SLE) patients, we observed a gelatinolytic molecule at 80 kDa, suggestive for activated human MMP-9. However, by developing and using the EDTA/gelatin zymography method and after purification of the 80 kDa entity, we proved that this molecule was the C1s subunit of the complement system. The zymolytic capacity of C1s was validated and found to be enhanced, in the absence of calcium and in the presence of EDTA. Our findings indicate that for correct identification of gelatinolytic proteins in complex biological samples the use of EDTA/gelatin zymography for enzyme development is advised. In addition, by quantification of EDTA/gelatin zymography analysis and ELISA, we observed that the levels of C1s were higher in plasma and immune complexes of SLE patients than of healthy individuals. Therefore, our data imply that C1s may become a marker for the diagnosis of SLE.


Assuntos
Complexo Antígeno-Anticorpo/imunologia , Ácido Edético/química , Gelatina/química , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/imunologia , Metaloproteinase 9 da Matriz/sangue , Adolescente , Adulto , Idoso , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Gelatinases/metabolismo , Humanos , Lúpus Eritematoso Sistêmico/metabolismo , Masculino , Metaloproteinase 2 da Matriz/sangue , Pessoa de Meia-Idade , Adulto Jovem
18.
Biochem Biophys Res Commun ; 520(1): 198-204, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31585732

RESUMO

Increased angiogenesis is commonly observed in chronic lymphocytic leukemia (CLL) tissues in correlation with advanced disease. CLL cells express pro- and anti-angiogenic genes and acquire a pro-angiogenic pattern upon interaction with the microenvironment. Because MMP-9 (a microenvironment component) plays important roles in solid tumor angiogenesis, we have studied whether MMP-9 influenced the angiogenic pattern in CLL cells. Immunofluorescence analyses confirmed the presence of MMP-9 in CLL tissues. MMP-9 interaction with CLL cells increased their MMP-9 expression and secretion into the medium. Accordingly, the conditioned media of MMP-9-primed CLL cells significantly enhanced endothelial cell proliferation, compared to control cells. MMP-9 also increased VEGF and decreased TSP-1 and Ang-2 expression, all at the gene and protein level, inducing a pro-angiogenic pattern in CLL cells. Mechanistic analyses demonstrated that downregulation of the selected gene TSP-1 by MMP-9 involved α4ß1 integrin, Src kinase family activity and the STAT3 transcription factor. Regulation of angiogenic genes is a novel contribution of MMP-9 to CLL pathology.


Assuntos
Angiopoietina-2/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Leucemia Linfocítica Crônica de Células B/enzimologia , Metaloproteinase 9 da Matriz/metabolismo , Neovascularização Patológica , Fator de Transcrição STAT3/metabolismo , Idoso , Proliferação de Células , Meios de Cultivo Condicionados , Células Endoteliais/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Leucêmica da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Integrina alfa4beta1/metabolismo , Masculino , Pessoa de Meia-Idade
19.
Clin Oral Investig ; 23(7): 2823-2835, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31093743

RESUMO

OBJECTIVES: Matrix metalloproteinase (MMP) expression has been associated with tissue development, invasive cancer cell behavior, and inflammation. The associations of increased expression of MMPs with diseases have led to intensive research activities to develop MMP inhibitors. Here, the questions are addressed which associations between increased levels of any MMP with dental diseases may be cause or consequence, whether MMP levels may be of diagnostic value and whether and which MMP inhibitors need further investigations for use in dental diseases. METHODS: To study the role of MMPs and to discriminate between cause or consequence, the literature about measurements of MMPs and about the use of inhibitory drugs and genetic knockout animal models in dentistry was compared. RESULTS: The only FDA-approved treatment with MMP inhibitors is tetracyclines for periodontitis, whereas a diagnostic test for activated MMP-8 in oral fluids is valued in practical periodontology. The MMP literature in dentistry is artificially skewed to the gelatinases MMP-2 and MMP-9 and to enamelysin, alias MMP-20. The basis for this observation is, respectively, the widely used and sensitive technique of gelatin zymography and enamel proteins as substrates of MMP-20. Studies on additional MMPs are gaining interest in dentistry and MMP inhibitors may provide new applications. In addition, drugs with proven effects for the treatment of dental diseases may be found to act through MMP inhibition. CONCLUSION AND RELEVANCE: In conclusion, research on MMPs and inhibitors may provide practical applications beyond diagnosis and treatment of periodontitis and will be, directly or indirectly, beneficial for patients with dental or periodontal diseases.


Assuntos
Inibidores de Metaloproteinases de Matriz , Periodontite , Animais , Odontologia/tendências , Humanos , Metaloproteinase 2 da Matriz , Metaloproteinase 9 da Matriz , Periodontite/tratamento farmacológico
20.
Crit Rev Biochem Mol Biol ; 51(5): 295-358, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27362691

RESUMO

Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) are thought to be predominant proteases and protease inhibitors involved in the pathogenesis of inflammatory bowel diseases (IBD) through their ability to remodel the extracellular matrix (ECM) in response to inflammatory stimuli and by their immunomodulating effects. An imbalance between MMPs and TIMPs has been linked with acute and chronic inflammation and aberrant tissue remodeling, as seen in IBD. Moreover, recurrent phases of tissue destruction and subsequent tissue repair can cause serious complications in IBD patients such as fistulas and fibrosis. The aims of this review are (i) to summarize current literature on genetic association, mRNA, and protein expression studies with regard to MMPs and TIMPs in IBD patients and various animal models, including those with transgenic and knockout mice; (ii) to compare biochemical and molecular biological data in humans with those obtained in animal model studies and (iii) to critically evaluate and translate how this knowledge may be used in practical terms to understand better the pathophysiology and mechanisms operating in IBD and to apply this for improvement of clinical outcomes at diagnostic, prognostic and therapeutic levels.


Assuntos
Matriz Extracelular/imunologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/imunologia , Inibidores de Metaloproteinases de Matriz/uso terapêutico , Metaloproteinases da Matriz/imunologia , Inibidores Teciduais de Metaloproteinases/imunologia , Animais , Matriz Extracelular/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/patologia , Humanos , Doenças Inflamatórias Intestinais/patologia , Inibidores de Metaloproteinases de Matriz/farmacologia , Mapas de Interação de Proteínas/efeitos dos fármacos
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