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1.
Int J Mol Sci ; 23(3)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35163566

RESUMO

The Helicobacter pylori Neutrophil Activating Protein (HP-NAP) is endowed with immunomodulatory properties that make it a potential candidate for anticancer therapeutic applications. By activating cytotoxic Th1 responses, HP-NAP inhibits the growth of bladder cancer and enhances the anti-tumor activity of oncolytic viruses in the treatment of metastatic breast cancer and neuroendocrine tumors. The possibility that HP-NAP exerts its anti-tumor effect also by modulating the activity of innate immune cells has not yet been explored. Taking advantage of the zebrafish model, we examined the therapeutic efficacy of HP-NAP against metastatic human melanoma, limiting the observational window to 9 days post-fertilization, well before the maturation of the adaptive immunity. Human melanoma cells were xenotransplanted into zebrafish embryos and tracked in the presence or absence of HP-NAP. The behavior and phenotype of macrophages and the impact of their drug-induced depletion were analyzed exploiting macrophage-expressed transgenes. HP-NAP administration efficiently inhibited tumor growth and metastasis and this was accompanied by strong recruitment of macrophages with a pro-inflammatory profile at the tumor site. The depletion of macrophages almost completely abrogated the ability of HP-NAP to counteract tumor growth. Our findings highlight the pivotal role of activated macrophages in counteracting melanoma growth and support the notion that HP-NAP might become a new biological therapeutic agent for the treatment of metastatic melanomas.


Assuntos
Proteínas de Bactérias/administração & dosagem , Macrófagos/metabolismo , Melanoma/tratamento farmacológico , Animais , Proteínas de Bactérias/imunologia , Linhagem Celular Tumoral , Polaridade Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Melanoma/imunologia , Metástase Neoplásica , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra
2.
Cell Microbiol ; 21(5): e13006, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30646431

RESUMO

Helicobacter pylori (HP) is a Gram-negative bacterium that chronically infects the stomach of more than 50% of human population and represents a major cause of gastric cancer, gastric lymphoma, gastric autoimmunity, and peptic ulcer. It still remains to be elucidated, which HP virulence factors are important in the development of gastric disorders. Here, we analysed the role of the HP protein HP1454 in the host-pathogen interaction. We found that a significant proportion of T cells isolated from HP patients with chronic gastritis and gastric adenocarcinoma proliferated in response to HP1454. Moreover, we demonstrated in vivo that HP1454 protein drives Th1/Th17 inflammatory responses. We further analysed the in vitro response of human T cells exposed either to an HP wild-type strain or to a strain with a deletion of the hp1454 gene, and we revealed that HP1454 triggers the T-cell antigen receptor-dependent signalling and lymphocyte proliferation, as well as the CXCL12-dependent cell adhesion and migration. Our study findings prove that HP1454 is a crucial bacterial factor that exerts its proinflammatory activity by directly modulating the T-cell response. The relevance of these results can be appreciated by considering that compelling evidence suggest that chronic gastric inflammation, a condition that paves the way to HP-associated diseases, is dependent on T cells.


Assuntos
Adenocarcinoma/imunologia , Gastrite/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/metabolismo , Lipoproteínas/imunologia , Neoplasias Gástricas/imunologia , Linfócitos T/imunologia , Adenocarcinoma/microbiologia , Idoso , Adesão Celular/imunologia , Diferenciação Celular/imunologia , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Movimento Celular/imunologia , Feminino , Mucosa Gástrica/imunologia , Mucosa Gástrica/microbiologia , Mucosa Gástrica/ultraestrutura , Gastrite/microbiologia , Regulação da Expressão Gênica/imunologia , Helicobacter pylori/genética , Helicobacter pylori/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas R-SNARE/genética , Proteínas R-SNARE/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Neoplasias Gástricas/microbiologia , Células Th1/imunologia , Células Th17/imunologia
3.
Biochim Biophys Acta Gen Subj ; 1861(12): 3263-3271, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28947343

RESUMO

BACKGROUND: Helicobacter pylori is a bacterium that affects about 50% of the world population and, despite being often asymptomatic, it is responsible of several gastric diseases, from gastritis to gastric cancer. The protein Lpp20 (HP1456) plays an important role in bacterium survival and host colonization, but the possibility that it might be involved in the etiology of H. pylori-related disorders is an unexplored issue. Lpp20 is a lipoprotein bound to the external membrane of the bacterium, but it is also secreted inside vesicles along with other two proteins of the same operon, i.e. HP1454 and HP1457. RESULTS: In this study we determined the crystal structure of Lpp20 and we found that it has a fold similar to a carcinogenic factor released by H. pylori, namely Tipα. We demonstrate that Lpp20 promotes cell migration and E-cadherin down-regulation in gastric cancer cells, two events recalling the epithelial-mesenchymal transition (EMT) process. Differently from Tipα, Lpp20 also stimulates cell proliferation. CONCLUSIONS: This identifies Lpp20 as a new pathogenic factor produced by H. pylori that promotes EMT and thereby the progression of cancer to the metastatic state.


Assuntos
Antígenos de Bactérias/química , Proteínas de Bactérias/química , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Helicobacter pylori/patogenicidade , Lipoproteínas/química , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/toxicidade , Caderinas/análise , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Lipoproteínas/imunologia , Lipoproteínas/toxicidade , Dobramento de Proteína , Estrutura Secundária de Proteína , Neoplasias Gástricas/etiologia , Neoplasias Gástricas/patologia
4.
J Immunol ; 193(11): 5584-94, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25339679

RESUMO

BAFF is a crucial cytokine that affects the activity of both innate and adaptive immune cells. It promotes the expansion of Th17 cells in autoimmune disorders. With this study, we investigated the BAFF/Th17 responses in Helicobacter pylori-induced gastritis in humans. Our results show that the mucosa from Helicobacter(+) patients with chronic gastritis is enriched in IL-17 and BAFF, whereas the two cytokines are weakly expressed in Helicobacter(-) patients with chronic gastritis; moreover, the expression of both BAFF and IL-17 decreases after bacteria eradication. We demonstrate that BAFF accumulates in macrophages in vivo and that it is produced by monocyte-derived macrophages in vitro, after Helicobacter stimulation. Application of BAFF on monocytes triggers the accumulation of reactive oxygen species that are crucial for the release of pro-Th17 cytokines, such as IL-23, IL-1ß, and TGF-ß. Moreover, BAFF directly promotes the differentiation of Th17 cells. In conclusion, our results support the notion that an axis BAFF/Th17 exists in chronic gastritis of Helicobacter(+) patients and that its presence strictly depends on the bacterium. Moreover, we demonstrated that BAFF is able to drive Th17 responses both indirectly, by creating a pro-Th17 cytokine milieu through the involvement of innate immune cells, and directly, via the differentiation of T cells toward the specific profile. The results obtained in this study are of great interest for Helicobacter-related diseases and the development of novel therapeutic strategies based on the inhibition of the BAFF/IL-17 response.


Assuntos
Fator Ativador de Células B/metabolismo , Gastrite/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Macrófagos/imunologia , Mucosa/imunologia , Células Th17/imunologia , Imunidade Adaptativa , Diferenciação Celular , Células Cultivadas , Doença Crônica , Gastrite/etiologia , Infecções por Helicobacter/complicações , Humanos , Imunidade Inata , Interleucina-17/metabolismo , Macrófagos/microbiologia , Mucosa/microbiologia , Espécies Reativas de Oxigênio/metabolismo
5.
Cell Microbiol ; 16(6): 925-37, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24397470

RESUMO

Neisseria meningitidis is a human pathogen that can cause fatal sepsis and meningitis once it reaches the blood stream and the nervous system. Here we demonstrate that a fragment, released upon proteolysis of the surface-exposed protein Neisserial Heparin Binding Antigen (NHBA), by the bacterial protease NalP, alters the endothelial permeability by inducing the internalization of the adherens junction protein VE-cadherin. We found that C2 rapidly accumulates in mitochondria where it induces the production of reactive oxygen species: the latter are required for the phosphorylation of the junctional protein and for its internalization that, in turn, is responsible for the endothelial leakage. Our data support the notion that the NHBA-derived fragment C2 might contribute to the extensive vascular leakage typically associated with meningococcal sepsis.


Assuntos
Junções Aderentes/efeitos dos fármacos , Antígenos de Bactérias/metabolismo , Células Endoteliais/efeitos dos fármacos , Neisseria meningitidis/fisiologia , Permeabilidade/efeitos dos fármacos , Antígenos de Bactérias/genética , Linhagem Celular , Humanos , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
6.
Arthritis Rheum ; 65(5): 1232-42, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23371320

RESUMO

OBJECTIVE: Lyme arthritis (LA) is characterized by infiltration of inflammatory cells, mainly neutrophils (polymorphonuclear cells [PMNs]) and T cells, into the joints. This study was undertaken to evaluate the role of the neutrophil-activating protein A (NapA) of Borrelia burgdorferi in eliciting inflammation and in driving the adaptive immune response. METHODS: Levels of NapA, interferon-γ (IFNγ), interleukin-17 (IL-17), and T cell-attracting chemokines were assessed by enzyme-linked immunosorbent assay in synovial fluid from patients with LA. The profile of T cells recruited into the synovia of patients with LA was defined by fluorescence-activated cell sorting analysis. NapA was intraarticularly injected into rat knees, and the cells recruited in synovia were characterized. The role of NapA in recruiting immune cells was confirmed by chemotaxis assays using a Transwell system. RESULTS: NapA, IFNγ, IL-17, CCL2, CCL20, and CXCL10 accumulated in synovial fluid from patients with LA. Accordingly, T cells obtained from these patients produced IFNγ or IL-17, but notably, some produced both cytokines. NapA promoted neutrophil and T lymphocyte recruitment both in vitro and in vivo. Interestingly, the infiltration of T cells not only resulted from the chemotactic activity of NapA but also relied on the chemokines produced by PMNs exposed to NapA. CONCLUSION: We provide evidence that NapA functions as one of the main bacterial products involved in the pathogenesis of LA. Accordingly, we show that, at very early stages of LA, NapA accumulates and, in turn, orchestrates the recruitment of inflammatory cells into the joint cavity. Thereafter, with the contribution of recruited cells, NapA promotes the infiltration of T cells producing IL-17 and/or IFNγ.


Assuntos
Imunidade Adaptativa/imunologia , Artrite Infecciosa/imunologia , Proteínas de Bactérias/imunologia , Quimiocinas CXC/imunologia , Doença de Lyme/imunologia , Animais , Artrite Infecciosa/etiologia , Artrite Infecciosa/patologia , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/metabolismo , Borrelia burgdorferi/fisiologia , Quimiocinas/análise , Quimiocinas/metabolismo , Quimiocinas CXC/administração & dosagem , Quimiocinas CXC/metabolismo , Quimiotaxia/efeitos dos fármacos , Feminino , Citometria de Fluxo , Humanos , Injeções Intra-Articulares , Articulação do Joelho/metabolismo , Articulação do Joelho/patologia , Doença de Lyme/complicações , Doença de Lyme/patologia , Masculino , Pessoa de Meia-Idade , Infiltração de Neutrófilos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/patologia , Ratos , Joelho de Quadrúpedes/efeitos dos fármacos , Joelho de Quadrúpedes/patologia , Líquido Sinovial/química , Líquido Sinovial/metabolismo , Membrana Sinovial/patologia , Linfócitos T/metabolismo , Linfócitos T/patologia
7.
Cancer Immunol Immunother ; 61(1): 31-40, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21833592

RESUMO

Intravesical Bacillus Calmette-Guérin (BCG) is the gold standard treatment for intermediate and high-risk non-muscle-invasive bladder cancer. BCG therapy is the most successful example of immunotherapy in cancer. Unfortunately, the treatment-related side effects are still relevant. Furthermore, non-responder patients are candidate to radical cystectomy in the absence of valuable alternative options. These aspects have prompted the search for newer biological response modifiers (BRM) with a better benefit/side effects ratio. The toll-like receptor (TLR) 2 ligand, Helicobacter pylori protein HP-NAP, has been shown to deserve a potential role as BRM. HP-NAP is capable of driving the differentiation of T helper (Th) 1 cells, both in vitro and in vivo, because of its ability to create an IL-12-enriched milieu. Herein, we report that local administration of HP-NAP decreases tumour growth by triggering tumour necrosis in a mouse model of bladder cancer implant. The effect is accompanied by a significant accumulation of both CD4+ and CD8+ IFN-γ-secreting cells, within tumour and regional lymph nodes. Noteworthy, HP-NAP-treated tumours show also a reduced vascularization due to the anti-angiogenic activity of IFN-γ induced by HP-NAP. Our findings strongly indicate that HP-NAP might become a novel therapeutic "bullet" for the cure of bladder tumours.


Assuntos
Vacina BCG/farmacologia , Proteínas de Bactérias/farmacologia , Helicobacter pylori/imunologia , Células Th1/imunologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/imunologia , Administração Intravesical , Animais , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Feminino , Humanos , Imunoterapia , Camundongos , Camundongos Endogâmicos C57BL , Células Th1/metabolismo , Neoplasias da Bexiga Urinária/patologia
8.
Front Immunol ; 13: 944139, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35844568

RESUMO

The miniferritin HP-NAP of Helicobacter pylori was originally described as a neutrophil-activating protein because of the capacity to activate neutrophils to generate oxygen radicals and adhere to endothelia. Currently, the main feature for which HP-NAP is known is the ability to promote Th1 responses and revert the immune suppressive profile of macrophages. In this review, we discuss the immune modulating properties of the protein regarding the H. pylori infection and the evidence that support the potential clinical application of HP-NAP in allergy and cancer immunotherapy.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Proteínas de Bactérias , Humanos , Imunomodulação , Neutrófilos
9.
Biochim Biophys Acta ; 1804(12): 2191-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20851780

RESUMO

NapA from Borrelia burgdorferi is a member of the Dps-like protein family with specific immunomodulatory properties; in particular, NapA is able to induce the expression of IL-23 in neutrophils and monocytes, as well as the expression of IL-6, IL-1ß, and transforming growth factor beta (TGF-ß) in monocytes, via Toll-like receptor (TLR) 2. Such an activity on innate immune cells triggers a synovial fluid Th17 response. Here we report the crystal structure of NapA, determined at 2.6Å resolution, which shows that the quaternary structure of the protein is that of a dodecamer with 23 symmetry, typical of the proteins of the family. We also demonstrate that the N- and C-terminal tails, which are flexible and not visible in the crystal, are not relevant for its pro-Th17 activity. Based on the crystal structure and on the comparison with the structure of the orthologous protein from Helicobacter pylori, HP-NAP, we hypothesize that the charge distributions on the two proteins' surfaces are responsible for the interaction with TLR2 and for the different behaviors in modulating the immune response.


Assuntos
Proteínas de Bactérias/química , Quimiocinas CXC/química , Monócitos/metabolismo , Estrutura Quaternária de Proteína , Sequência de Aminoácidos , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Sítios de Ligação/genética , Células Cultivadas , Quimiocinas CXC/genética , Quimiocinas CXC/farmacologia , Cristalografia por Raios X , Citocinas/genética , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Expressão Gênica/efeitos dos fármacos , Humanos , Fatores Imunológicos/farmacologia , Modelos Moleculares , Dados de Sequência Molecular , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Mutação , Multimerização Proteica , Estrutura Terciária de Proteína , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Receptor 2 Toll-Like/imunologia , Receptor 2 Toll-Like/metabolismo
10.
Cancers (Basel) ; 13(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34680345

RESUMO

Tumor-associated macrophages (TAMs) are major components of the tumor microenvironment. In colorectal cancer (CRC), a strong infiltration of TAMs is accompanied by a decrease in effector T cells and an increase in the metastatic potential of CRC. We investigated the functional profile of TAMs infiltrating CRC tissue by immunohistochemistry, flow cytometry, ELISA, and qRT-PCR and their involvement in impairing the activation of effector T cells. In CRC biopsies, we evidenced a high percentage of macrophages with low expression of the antigen-presenting complex MHC-II and high expression of CD206. Monocytes co-cultured with tumor cells or a decellularized tumor matrix differentiated toward a pro-tumoral macrophage phenotype characterized by decreased expression of MHC-II and CD86 and increased expression of CD206 and an abundant release of pro-tumoral cytokines and chemokines. We demonstrated that the hampered expression of MHC-II in macrophages is due to the downregulation of the MHC-II transactivator CIITA and that this effect relies on increased expression of miRNAs targeting CIITA. As a result, macrophages become unable to present antigens to CD4 T lymphocytes. Our data suggest that the tumor microenvironment contributes to defining a pro-tumoral profile of macrophages infiltrating CRC tissue with impaired capacity to activate T cell effector functions.

11.
Sci Rep ; 10(1): 16501, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020563

RESUMO

CD300e is a surface receptor, expressed by myeloid cells, involved in the tuning of immune responses. CD300e engagement was reported to provide the cells with survival signals, to trigger the expression of activation markers and the release of pro-inflammatory cytokines. Hence, CD300e is considered an immune activating receptor. In this study, we demonstrate that the ligation of CD300e in monocytes hampers the expression of the human leukocyte antigen (HLA) class II, affecting its synthesis. This effect, which is associated with the transcription impairment of the signal transducer and activator of transcription 1 (STAT1), overcomes the capacity of interferon gamma (IFN-γ) to promote the expression of the antigen-presenting molecules. Importantly, the decreased expression of HLA-II on the surface of CD300e-activated monocytes negatively impacts their capacity to activate T cells in an antigen-specific manner. Notably, unlike in vitro- differentiated macrophages which do not express CD300e, the immune receptor is expressed by tissue macrophages. Taken together, our findings argue against the possibility that this molecule should be considered an activating immune receptor sensu stricto. Moreover, our results support the notion that CD300e might be a new player in the regulation of the expansion of T cell-mediated responses.


Assuntos
Ativação Linfocitária/imunologia , Receptores Imunológicos/metabolismo , Fator de Transcrição STAT1/metabolismo , Apresentação de Antígeno/imunologia , Linhagem Celular , Citocinas/metabolismo , Antígenos HLA/metabolismo , Voluntários Saudáveis , Humanos , Interferon gama/metabolismo , Monócitos/metabolismo , Transdução de Sinais , Linfócitos T/imunologia
12.
J Clin Invest ; 116(4): 1092-101, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16543949

RESUMO

The Helicobacter pylori neutrophil-activating protein (HP-NAP) is a virulence factor of H. pylori that stimulates in neutrophils high production of oxygen radicals and adhesion to endothelial cells. We report here that HP-NAP is a TLR2 agonist able to induce the expression of IL-12 and IL-23 by neutrophils and monocytes. Addition in culture of HP-NAP, as an immune modulator, to antigen-induced T cell lines resulted in a remarkable increase in the number of IFN-gamma-producing T cells and decrease of IL-4-secreting cells, thus shifting the cytokine profile of antigen-activated human T cells from Th2 to a Th1 cytotoxic phenotype. We also found that in vivo HP-NAP elicited an antigen-specific Th1-polarized T cell response in the gastric mucosa of H. pylori-infected patients. These data indicate HP-NAP as an important factor of H. pylori able to elicit cells of the innate immune system to produce IL-12 and IL-23, and they suggest it as a new tool for promoting Th1 immune responses.


Assuntos
Proteínas de Bactérias/metabolismo , Helicobacter pylori/metabolismo , Células Th1/imunologia , Adulto , Alérgenos/metabolismo , Alérgenos/farmacologia , Proteínas de Bactérias/farmacologia , Antígenos CD4/metabolismo , Células Cultivadas , Células Dendríticas/metabolismo , Feminino , Genes MHC da Classe II , Granulócitos/metabolismo , Humanos , Imunidade Inata , Interferon gama/metabolismo , Interleucina-12/biossíntese , Interleucina-23 , Subunidade p19 da Interleucina-23 , Interleucinas/biossíntese , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Neutrófilos/metabolismo , Fenótipo , Células Th1/metabolismo , Fatores de Tempo , Receptor 2 Toll-Like/agonistas , Receptor 2 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
13.
Cell Microbiol ; 10(11): 2355-63, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18671823

RESUMO

The Helicobacter pylori neutrophil-activating protein (HP-NAP) is able in vitro to elicit IL-12 and IL-23 production via agonistic interaction with toll-like receptor 2, and to promote Th1 polarization of allergen-specific T-cell responses. This study was aimed to assess whether systemic/intraperitoneal and/or mucosal HP-NAP administration inhibited the Th2-mediated bronchial inflammation using a mouse model of allergic asthma induced by inhaled ovalbumin (OVA). Systemic HP-NAP delivery markedly reduced the lung eosinophilia in response to repeated challenge with aerosolized OVA. Likewise, the production of IL-4, IL-5 and GM-CSF was significantly lower in the bronchoalveolar lavage of animals treated with systemic HP-NAP plus OVA than that of animals treated with OVA alone. Systemic HP-NAP also significantly resulted in both reduction of total serum IgE and increase of IL-12 plasma levels. Mucosal administration of HP-NAP was equally successful as the systemic delivery in reducing eosinophilia, IgE and Th2 cytokine levels in bronchoalveolar lavage. However, no suppression of lung eosinophilia and bronchial Th2 cytokines was observed in toll-like receptor 2-knock-out mice following HP-NAP treatment. These results identify HP-NAP as a candidate for novel strategies of prevention and treatment of allergic diseases.


Assuntos
Asma/imunologia , Proteínas de Bactérias/imunologia , Inflamação/imunologia , Neutrófilos/imunologia , Células Th2/imunologia , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/genética , Líquido da Lavagem Broncoalveolar/citologia , Citocinas/sangue , Citocinas/imunologia , Humanos , Imunoglobulina E/sangue , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ovalbumina/imunologia , Eosinofilia Pulmonar/imunologia
14.
J Allergy Clin Immunol ; 122(5): 908-913.e5, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18804852

RESUMO

BACKGROUND: The Helicobacter pylori neutrophil-activating protein (HP-NAP) is able to induce IL-12 expression by cells of innate immunity and to shift to T(H)1 human allergen-specific T(H)2 cells in vitro. OBJECTIVE: We performed an in vivo investigation of the ability of HP-NAP to downmodulate the T(H)2 response induced in mice by Trichinella spiralis infection. METHODS: Groups of T spiralis-infected BALB/c mice received intraperitoneal PBS/rat IgG2b (control animals) or 10 microg of HP-NAP with or without anti-Toll-like receptor 2 antibody on days 10 and 28 after infection. Blood eosinophils, total and T spiralis-specific IgE levels, and cytokine levels were measured in the plasma up to day 42, when splenocytes were cultured for cytokine production. RESULTS: Although control animals showed significant eosinophilia and increase of total and T spiralis-specific IgE, IL-4, and IL-5 levels from days 10 to 14, HP-NAP-treated animals showed less eosinophilia and total and excretory/secretory antigens of T spiralis-specific IgE in the blood. HP-NAP-treated animals also had higher IL-12 and IFN-gamma plasma levels and lower IL-4 and IL-5 levels. The addition of anti-Toll-like receptor 2 antibody abrogated the anti-T(H)2/pro-T(H)1 activity of HP-NAP. CONCLUSION: This study provides evidence that HP-NAP enhances endogenous IL-12 and IFN-gamma response and exerts a powerful anti-T(H)2 activity in vivo, targeting both IL-5-induced eosinophilia and IL-4-mediated hyper-IgE responses induced by parasitic infection.


Assuntos
Proteínas de Bactérias/imunologia , Células Th2/imunologia , Trichinella spiralis , Triquinelose/imunologia , Animais , Antígenos de Bactérias/imunologia , Modelos Animais de Doenças , Regulação para Baixo , Eosinofilia/imunologia , Feminino , Imunoglobulina E/imunologia , Interferon gama/imunologia , Interleucina-12/imunologia , Interleucina-4/imunologia , Interleucina-5/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Células Th1/imunologia
15.
Front Immunol ; 10: 2923, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31969878

RESUMO

Macrophages have a major role in infectious and inflammatory diseases, and the available data suggest that Helicobacter pylori persistence can be explained in part by the failure of the bacterium to be killed by professional phagocytes. Macrophages are cells ready to kill the engulfed pathogen, through oxygen-dependent and -independent mechanisms; however, their killing potential can be further augmented by the intervention of T helper (Th) cells upon the specific recognition of human leukocyte antigen (HLA)-II-peptide complexes on the surface of the phagocytic cells. As it pertains to H. pylori, the bacterium is engulfed by macrophages, but it interferes with the phagosome maturation process leading to phagosomes with an altered degradative capacity, and to megasomes, wherein H. pylori resists killing. We recently showed that macrophages infected with H. pylori strongly reduce the expression of HLA-II molecules on the plasma membrane and this compromises the bacterial antigen presentation to Th lymphocytes. In this work, we demonstrate that H. pylori hampers HLA-II expression in macrophages, activated or non-activated by IFN-γ, by down-regulating the expression of the class II major histocompatibility complex transactivator (CIITA), the "master control factor" for the expression of HLA class II genes. We provided evidence that this effect relies on the up-regulation of let-7f-5p, let-7i-5p, miR-146b-5p, and -185-5p targeting CIITA. MiRNA expression analysis performed on biopsies from H. pylori-infected patients confirmed the up-regulation of let-7i-5p, miR-146b-5p, and -185-5p in gastritis, in pre-invasive lesions, and in gastric cancer. Taken together, our results suggest that specific miRNAs may be directly involved in the H. pylori infection persistence and may contribute to confer the risk of developing gastric neoplasia in infected patients.


Assuntos
Antígenos HLA/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Macrófagos/imunologia , MicroRNAs/imunologia , Proteínas Nucleares/imunologia , Transativadores/imunologia , Regulação para Cima/imunologia , Idoso , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/imunologia
16.
Adv Healthc Mater ; 8(1): e1801307, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30511808

RESUMO

Considerable progress has been made in the field of microfluidics to develop complex systems for modeling human skin and dermal wound healing processes. While microfluidic models have attempted to integrate multiple cell types and/or 3D culture systems, to date they have lacked some elements needed to fully represent dermal wound healing. This paper describes a cost-effective, multicellular microfluidic system that mimics the paracrine component of early inflammation close to normal wound healing. Collagen and Matrigel are tested as materials for coating and adhesion of dermal fibroblasts and human umbilical vein endothelial cells (HUVECs). The wound-on-chip model consists of three interconnecting channels and is able to simulate wound inflammation by adding tumor necrosis factor alpha (TNF-α) or by triculturing with macrophages. Both the approaches significantly increase IL-1ß, IL-6, IL-8 in the supernatant (p < 0.05), and increases in cytokine levels are attenuated by cotreatment with an anti-inflammatory agent, Dexamethasone. Incorporation of M1 and M2 macrophages cocultured with fibroblasts and HUVECs leads to a stimulation of cytokine production as well as vascular structure formation, particularly with M2 macrophages. In summary, this wound-on-chip system can be used to model the paracrine component of the early inflammatory phase of wound healing and has the potential for the screening of anti-inflammatory compounds.


Assuntos
Microambiente Celular , Derme/patologia , Inflamação/patologia , Dispositivos Lab-On-A-Chip , Modelos Biológicos , Cicatrização , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Citocinas/metabolismo , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Inflamação/tratamento farmacológico , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Fator de Necrose Tumoral alfa
17.
Front Immunol ; 9: 2081, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30254646

RESUMO

Objective: To explore the effects of SERPINB3 administration in murine lupus models with a focus on lupus-like nephritis. Methods: 40 NZB/W F1 mice were subdivided into 4 groups and intraperitoneally injected with recombinant SERPINB3 (7.5 µg/0.1 mL or 15 µg/0.1 mL) or PBS (0.1 mL) before (group 1 and 2) or after (group 3 and 4) the development of proteinuria (≥100 mg/dl). Two additional mice groups were provided by including 20 MRL/lpr mice which were prophylactically injected with SERPINB3 (10 mice, group 5) or PBS (10 mice, group 6). Time of occurrence and levels of anti-dsDNA and anti-C1q antibodies, proteinuria and serum creatinine, overall- and proteinuria-free survival were assessed in mice followed up to natural death. Histological analysis was performed in kidneys of both lupus models. The Th17:Treg cell ratio was assessed by flow-cytometry in splenocytes of treated and untreated MRL/lpr mice. Statistical analysis was performed using non parametric tests and Kaplan-Meier curves, when indicated. Results: Autoantibody levels and proteinuria were significantly decreased and time of occurrence significantly delayed in SERPINB3-treated mice vs. controls. In agreement with these findings, proteinuria-free and overall survival were significantly improved in SERPINB3-treated groups vs. controls. Histological analysis demonstrated a lower prevalence of severe tubular lesions in kidneys of group 5 vs. group 6. SERPINB3-treated mice showed an overall trend toward a reduced prevalence of severe lesions in both strains. Th17:Treg ratio was significantly decreased in splenocytes of MRL/lpr mice treated with SERPINB3, compared to untreated control mice. Conclusions: SERPINB3 significantly improves disease course and delays the onset of severe glomerulonephritis in lupus-prone mice, possibly inducing a more tolerogenic immune phenotype.


Assuntos
Tolerância Imunológica/efeitos dos fármacos , Nefrite Lúpica , Serpinas/farmacologia , Linfócitos T Reguladores , Células Th17 , Animais , Autoanticorpos/imunologia , Modelos Animais de Doenças , Feminino , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/imunologia , Nefrite Lúpica/patologia , Camundongos , Camundongos Endogâmicos MRL lpr , Proteinúria/tratamento farmacológico , Proteinúria/imunologia , Proteinúria/patologia , Proteínas Recombinantes/farmacologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia , Células Th17/imunologia , Células Th17/patologia
19.
Front Immunol ; 8: 1288, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29085364

RESUMO

Helicobacter pylori (Hp) is a Gram-negative bacterium that infects the human gastric mucosa, leading to chronic inflammation. If not eradicated with antibiotic treatment, the bacterium persists in the human stomach for decades increasing the risk to develop chronic gastritis, gastroduodenal ulcer, and gastric adenocarcinoma. The lifelong persistence of Hp in the human stomach suggests that the host response fails to clear the infection. It has been recently shown that during Hp infection phagocytic cells promote high Hp loads rather than contributing to bacterial clearance. Within these cells Hp survives in "megasomes," large structures arising from homotypic fusion of phagosomes, but the mechanism that Hp employs to avoid phagocytic killing is not completely understood. Here, we show that Hp infection induces the downregulation of specific microRNAs involved in the regulation of transcripts codifying for inflammatory proteins. miR-4270 targets the most upregulated gene: the immune receptor CD300E, whose expression is strictly dependent on Hp infection. CD300E engagement enhances the pro-inflammatory potential of macrophages, but in parallel it affects their ability to express and expose MHC class II molecules on the plasma membrane, without altering phagocytosis. This effect compromises the possibility for effector T cells to recognize and activate the killing potential of macrophages, which, in turn would become a survival niche for the bacterium. Taken together, our data add another piece to the complicate puzzle represented by the long-life coexistence between Hp and the human host and contribute with new insights toward understanding the regulation and function of the immune receptor CD300E.

20.
Sci Rep ; 7: 40515, 2017 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-28074932

RESUMO

Recent studies have shown that certain specific microbial infections participate in atherosclerosis by inducing inflammation and immune reactions, but how the pathogens implicated in this pathology trigger the host responses remains unknown. In this study we show that Helicobacter cinaedi (Hc) is a human pathogen linked to atherosclerosis development since at least 27% of sera from atherosclerotic patients specifically recognize a protein of the Hc proteome, that we named Cinaedi Atherosclerosis Inflammatory Protein (CAIP) (n = 71). CAIP appears to be implicated in this pathology because atheromatous plaques isolated from atherosclerotic patients are enriched in CAIP-specific T cells (10%) which, in turn, we show to drive a Th1 inflammation, an immunopathological response typically associated to atherosclerosis. Recombinant CAIP promotes the differentiation and maintenance of the pro-inflammatory profile of human macrophages and triggers the formation of foam cells, which are a hallmark of atherosclerosis. This study identifies CAIP as a relevant factor in atherosclerosis inflammation linked to Hc infection and suggests that preventing and eradicating Hc infection could reduce the incidence of atherosclerosis.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Aterosclerose/sangue , Aterosclerose/imunologia , Diferenciação Celular , Células Espumosas/patologia , Helicobacter/imunologia , Inflamação/imunologia , Idoso , Aterosclerose/microbiologia , Polaridade Celular , Quimiocinas/metabolismo , Cristalografia por Raios X , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Células Espumosas/metabolismo , Humanos , Inflamação/sangue , Lipoproteínas LDL/metabolismo , Sistema de Sinalização das MAP Quinases , Ativação de Macrófagos , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Fenótipo , Placa Aterosclerótica/sangue , Placa Aterosclerótica/patologia , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Recombinantes/metabolismo , Células Th1/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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