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1.
Front Immunol ; 13: 801120, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35154114

RESUMO

An increase in mast cells (MCs) and MCs mediators has been observed in malaria-associated bacteremia, however, the role of these granulocytes in malarial immunity is poorly understood. Herein, we studied the role of mouse MC protease (Mcpt) 4, an ortholog of human MC chymase, in malaria-induced bacteremia using Mcpt4 knockout (Mcpt4-/-) mice and Mcpt4+/+ C57BL/6J controls, and the non-lethal mouse parasite Plasmodium yoelii yoelii 17XNL. Significantly lower parasitemia was observed in Mcpt4-/- mice compared with Mcpt4+/+ controls by day 10 post infection (PI). Although bacterial 16S DNA levels in blood were not different between groups, increased intestinal permeability to FITC-dextran and altered ileal adherens junction E-cadherin were observed in Mcpt4-/- mice. Relative to infected Mcpt4+/+ mice, ileal MC accumulation in Mcpt4-/- mice occurred two days earlier and IgE levels were higher by days 8-10 PI. Increased levels of circulating myeloperoxidase were observed at 6 and 10 days PI in Mcpt4+/+ but not Mcpt4-/- mice, affirming a role for neutrophil activation that was not predictive of parasitemia or bacterial 16S copies in blood. In contrast, early increased plasma levels of TNF-α, IL-12p40 and IL-3 were observed in Mcpt4-/- mice, while levels of IL-2, IL-10 and MIP1ß (CCL4) were increased over the same period in Mcpt4+/+ mice, suggesting that the host response to infection was skewed toward a type-1 immune response in Mcpt4-/- mice and type-2 response in Mcpt4+/+ mice. Spearman analysis revealed an early (day 4 PI) correlation of Mcpt4-/- parasitemia with TNF-α and IFN-γ, inflammatory cytokines known for their roles in pathogen clearance, a pattern that was observed in Mcpt4+/+ mice much later (day 10 PI). Transmission success of P. y. yoelii 17XNL to Anopheles stephensi was significantly higher from infected Mcpt4-/- mice compared with infected Mcpt4+/+ mice, suggesting that Mcpt4 also impacts transmissibility of sexual stage parasites. Together, these results suggest that early MCs activation and release of Mcpt4 suppresses the host immune response to P. y. yoelii 17XNL, perhaps via degradation of TNF-α and promotion of a type-2 immune response that concordantly protects epithelial barrier integrity, while limiting the systemic response to bacteremia and parasite transmissibility.


Assuntos
Anopheles/parasitologia , Permeabilidade da Membrana Celular/imunologia , Quimases/genética , Quimases/imunologia , Interações Hospedeiro-Parasita/imunologia , Malária/imunologia , Mastócitos/enzimologia , Plasmodium yoelii/imunologia , Animais , Feminino , Íleo/citologia , Íleo/patologia , Mastócitos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Fator de Necrose Tumoral alfa/metabolismo
2.
Bull Exp Biol Med ; 171(3): 352-356, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34297293

RESUMO

To better explore the pathophysiology of FA and its therapy, we aimed to establish a simple and practicable FA model with Freund's adjuvant and introduce an easy and reliable laboratory evaluation method for assessment of inflammation in intestinal segments at different anatomical locations. BALB/c mice were sensitized with ovalbumin combined with Freund's adjuvant. Complete Freund's adjuvant was chosen for the first sensitization and two weeks later incomplete Freund's adjuvant was used for a second sensitization. Two weeks later, the sensitized mice were challenged with 50 mg ovalbumin every other day. After the 6 challenge, all mice were assessed for systemic anaphylaxis, and then sacrificed for sample collection. All sensitized mice showed anaphylactic symptoms and markedly increased levels of serum ovalbumin-specific IgE and IgG1. The activity of mast cell protease-1 (mMCPT-1) was significantly increased in the serum and interstitial fluid of the duodenum, jejunum, ileum, and colon. A successful FA model was established, of which inflammation occurred in the duodenum, jejunum, ileum, and colon. This model provides a reliable and simple tool for analysis of the mechanism of FA and methods of immunotherapy. Moreover, combined detection of ovalbumin-specific antibody and local mMCPT-1 levels could potentially be used as the major indicator for assessment of food allergy.


Assuntos
Anafilaxia/imunologia , Quimases/genética , Hipersensibilidade a Ovo/imunologia , Adjuvante de Freund/administração & dosagem , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Ovalbumina/administração & dosagem , Anafilaxia/induzido quimicamente , Anafilaxia/genética , Anafilaxia/patologia , Animais , Biomarcadores/metabolismo , Quimases/imunologia , Colo/imunologia , Colo/patologia , Duodeno/imunologia , Duodeno/patologia , Hipersensibilidade a Ovo/genética , Hipersensibilidade a Ovo/patologia , Líquido Extracelular/química , Líquido Extracelular/imunologia , Feminino , Expressão Gênica , Íleo/imunologia , Íleo/patologia , Jejuno/imunologia , Jejuno/patologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia
4.
J Innate Immun ; 12(5): 357-372, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32498069

RESUMO

Mast cells are now recognized as key players in diverse pathologies, but the mechanisms by which they contribute in such settings are only partially understood. Mast cells are packed with secretory granules, and when they undergo degranulation in response to activation the contents of the granules are expelled to the extracellular milieu. Chymases, neutral serine proteases, are the major constituents of the mast cell granules and are hence released in large amounts upon mast cell activation. Following their release, chymases can cleave one or several of a myriad of potential substrates, and the cleavage of many of these could potentially have a profound impact on the respective pathology. Indeed, chymases have recently been implicated in several pathological contexts, in particular through studies using chymase inhibitors and by the use of chymase-deficient animals. In many cases, chymase has been shown to account for mast cell-dependent detrimental effects in the respective conditions and is therefore emerging as a promising drug target. On the other hand, chymase has been shown to have protective roles in other pathological settings. More unexpectedly, chymase has also been shown to control certain homeostatic processes. Here, these findings are reviewed.


Assuntos
Quimases/fisiologia , Mastócitos/enzimologia , Animais , Quimases/antagonistas & inibidores , Quimases/deficiência , Quimases/imunologia , Homeostase/efeitos dos fármacos , Humanos , Imunidade Inata/efeitos dos fármacos , Mastócitos/imunologia , Camundongos Knockout , Inibidores de Proteases/farmacologia
5.
J Allergy Clin Immunol ; 146(3): 642-651.e5, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32113980

RESUMO

BACKGROUND: Allergic inflammation is driven by IgE-producing plasma cells (PCs), which are required for IgE-mediated activation of mast cells and basophils. Repeated antigen encounter elicits a memory IgE response with elevated serum IgE titers and accumulation of IgE-producing PCs. However, the cellular compartment and molecular signals that underlie the immunologic memory of IgE responses remain unclear. OBJECTIVE: With this study we aimed at clarifying whether inactivation of the cytoplasmic immunoglobulin tail tyrosine (ITT) motif in transmembrane IgE (mIgE) impairs the memory IgE response in mice. METHODS: We generated mice with an inactivated mIgE-ITT motif and analyzed serum IgE levels as well as the generation of IgE-producing germinal center B cells and PCs subsequent to primary and secondary infection with helminths. In vitro cultures were used to study the mIgE-ITT-controlled expression of mIgE on the surface of PCs. Systemic mast cell activation was determined by serum Mcpt1 ELISA in response to ovalbumin challenge. RESULTS: mIgE-ITT-mutant mice showed an impaired memory IgE response subsequent to helminth infection. Furthermore, sensitization and challenge of mIgE-ITT-mutant mice with ovalbumin resulted in diminished serum IgE titers and reduced mast cell activation. The mIgE-ITT motif was required for optimal cell surface expression of mIgE B-cell antigen receptors but not for intracellular IgE expression in PCs. CONCLUSION: These results indicate that the mIgE B-cell antigen receptor plays a critical role in establishing or maintaining the population of IgE-producing PCs during memory IgE responses.


Assuntos
Imunoglobulina E/imunologia , Memória Imunológica , Plasmócitos/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Tricostrongiloidíase/imunologia , Alérgenos/imunologia , Animais , Quimases/imunologia , Feminino , Masculino , Mastócitos/imunologia , Camundongos Transgênicos , Ovalbumina/imunologia , Trichostrongyloidea
6.
Front Immunol ; 10: 2399, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681290

RESUMO

Mast cells (MCs) are considered as key effector cells in the elicitation of allergic symptoms, and they are essential players in innate and adaptive immune responses. In mice, two main types of MCs have been described: connective tissue MCs (CTMCs) and mucosal MCs (MMCs). However, little is known about the biological functions of MMCs, which is due to the lack of suitable models to investigate MMCs in vivo. Here, we aimed to generate a mouse model selectively deficient in MMCs. It has been previously described that Cre expressed under the control of the baboon α-chymase promotor is predominantly localized in MMCs. Therefore, we mated α-chymase-Cre transgenic mice with mice bearing a floxed allele of the myeloid cell leukemia sequence 1 (Mcl-1). Mcl-1 encodes for an intracellular antiapoptotic factor in MCs; hence, a selective reduction in MMCs was expected. Our results show that this new mouse model contains markedly reduced numbers of MMCs in mucosal tissues, whereas numbers of CTMCs are normal. Thus, Chm-Cre; Mcl-1fl/fl mice are a useful tool for the investigation of the pathophysiological functions of MMCs in vivo.


Assuntos
Quimases/deficiência , Mastócitos/imunologia , Modelos Imunológicos , Proteína de Sequência 1 de Leucemia de Células Mieloides/imunologia , Animais , Quimases/imunologia , Integrases/genética , Integrases/imunologia , Camundongos , Camundongos Transgênicos , Mucosa/imunologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética
7.
Nutrients ; 11(10)2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618852

RESUMO

Food proteins may get nitrated by various exogenous or endogenous mechanisms. As individuals might get recurrently exposed to nitrated proteins via daily diet, we aimed to investigate the effect of repeatedly ingested nitrated food proteins on the subsequent immune response in non-allergic and allergic mice using the milk allergen beta-lactoglobulin (BLG) as model food protein in a mouse model. Evaluating the presence of nitrated proteins in food, we could detect 3-nitrotyrosine (3-NT) in extracts of different foods and in stomach content extracts of non-allergic mice under physiological conditions. Chemically nitrated BLG (BLGn) exhibited enhanced susceptibility to degradation in simulated gastric fluid experiments compared to untreated BLG (BLGu). Gavage of BLGn to non-allergic animals increased interferon-γ and interleukin-10 release of stimulated spleen cells and led to the formation of BLG-specific serum IgA. Allergic mice receiving three oral gavages of BLGn had higher levels of mouse mast cell protease-1 (mMCP-1) compared to allergic mice receiving BLGu. Regardless of the preceding immune status, non-allergic or allergic, repeatedly ingested nitrated food proteins seem to considerably influence the subsequent immune response.


Assuntos
Alérgenos/imunologia , Lactoglobulinas/imunologia , Hipersensibilidade a Leite/imunologia , Nitrocompostos/imunologia , Animais , Linhagem Celular Tumoral , Quimases/imunologia , Quimases/metabolismo , Modelos Animais de Doenças , Feminino , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-10/imunologia , Interleucina-10/metabolismo , Camundongos Endogâmicos BALB C , Hipersensibilidade a Leite/sangue , Estabilidade Proteica , Proteólise , Ratos , Baço/imunologia , Baço/metabolismo , Tirosina/análogos & derivados , Tirosina/imunologia
8.
Mol Immunol ; 114: 535-544, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31518857

RESUMO

BACKGROUND: Mast cells are involved in the host immune response controlling infection with the non-invasive intestinal protozoan parasite Giardia intestinalis. Experimental infections in rodents with G. intestinalis showed increased intestinal expression of mucosal and connective mast cell specific proteases suggesting that both mucosal and connective tissue mast cells are recruited and activated during infection. During infection Giardia excretory-secretory proteins (ESPs) with immunomodulatory capacity are released. However, studies investigating potential interactions between Giardia ESPs and the connective tissue mast cell specific serine proteases, i.e. human chymase and mouse mast cell protease (mMCP)-4 and, human and mouse tryptase (mMCP-6) remain scarce. RESULTS: We first investigated if soluble Giardia proteins (sGPs), which over-lap extensively in protein content with ESP fractions, from the isolates GS, WB and H3, could induce mast cell activation. sGPs induced a minor activation of bone marrow derived mucosal-like mast cells, as indicated by increased IL-6 secretion and no degranulation. Furthermore, sGPs were highly resistant to degradation by human tryptase while human chymase degraded a 65 kDa sGP and, wild-type mouse ear tissue extracts degraded several protein bands in the 10 to 75 kDa range. In striking contrast, sGPs and ESPs were found to increase the enzymatic activity of human and mouse tryptase and to reduce the activity of human and mouse chymase. CONCLUSION: Our finding suggests that Giardia ssp. via enhancement or reduction of mast cell protease activity may modulate mast cell-driven intestinal immune responses. ESP-mediated modulation of the mast cell specific proteases may also increase degradation of tight junctions, which may be beneficial for Giardia ssp. during infection.


Assuntos
Quimases/imunologia , Giardia/imunologia , Giardíase/imunologia , Mastócitos/imunologia , Mastócitos/parasitologia , Triptases/imunologia , Animais , Endopeptidases/imunologia , Giardíase/parasitologia , Humanos , Intestinos/imunologia , Intestinos/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Proteólise , Serina Endopeptidases/imunologia
9.
J Allergy Clin Immunol ; 144(4S): S19-S30, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31369803

RESUMO

Mast cells (MCs) are capable of executing powerful inflammatory response programs triggered by surface IgE cross-linking or through pattern recognition receptors. The question of how MCs contribute to human disease has been intensely investigated and stimulated much controversy. Correlative evidence comes from human studies, pointing to pathogenetic or protective MC functions in patients with atopic conditions, autoimmune disorders, type 2 diabetes, chronic urticaria, mastocytosis, and cancer. Experiments in MC-deficient mice underpinned key roles for MCs in patients with IgE-mediated allergic conditions. Important pathogenetic MC contributions to other inflammatory and neoplastic conditions were suggested by studies in traditional KIT mutant MC-deficient mouse strains. However, many of these findings were not reproduced in more recently developed improved mouse models of MC deficiency, largely ruling out roles for MCs in mouse models for autoimmune disease, diabetes, and cancer. We discuss limitations of studies in mice and human subjects and provide suggestions for how they can be overcome, such as through the development of specific and selective MC-targeted treatments.


Assuntos
Imunoglobulina E/imunologia , Infecções/imunologia , Inflamação/imunologia , Mastócitos/imunologia , Neoplasias/imunologia , Ferimentos e Lesões/imunologia , Animais , Quimases/imunologia , Feminino , Humanos , Infecções/patologia , Inflamação/patologia , Ativação Linfocitária , Mastócitos/patologia , Neoplasias/patologia , Gravidez , Receptores de IgE/imunologia , Células Th2/imunologia , Células Th2/patologia , Receptor 2 Toll-Like/imunologia , Microambiente Tumoral/imunologia , Ferimentos e Lesões/patologia
10.
Curr Opin Allergy Clin Immunol ; 18(5): 370-376, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30048251

RESUMO

PURPOSE OF REVIEW: The aim of the review is to describe the different clinical pictures of anaphylaxis (phenotypes), in relation to the underlying mechanisms and potential biomarkers, to describe anaphylaxis endotypes. This may aid in achieving a better understanding, management and outcomes of such severe reactions. RECENT FINDINGS: Different anaphylaxis phenotypes have been outlined, ranging from the classical type-I-like to those suggestive of cytokine-storm-like or complement-mediated reactions. Underlying mechanisms differ and biomarkers of cells and systems involved are being identified (tryptase, IL-6, bradykinin etc.) SUMMARY: Identifying specific phenotypes/endotypes will allow the application of precision medicine in patients with anaphylaxis, providing insights to the most appropriate approach in each case.


Assuntos
Anafilaxia/imunologia , Biomarcadores/metabolismo , Ativação do Complemento/imunologia , Citocinas/imunologia , Fenótipo , Anafilaxia/metabolismo , Basófilos/imunologia , Bradicinina/imunologia , Bradicinina/metabolismo , Carboxipeptidases A/imunologia , Carboxipeptidases A/metabolismo , Quimases/imunologia , Quimases/metabolismo , Citocinas/metabolismo , Histamina/imunologia , Histamina/metabolismo , Humanos , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Interleucina-6/imunologia , Interleucina-6/metabolismo , Mastócitos/imunologia , Fator de Ativação de Plaquetas/imunologia , Fator de Ativação de Plaquetas/metabolismo , Medicina de Precisão , Triptases/imunologia , Triptases/metabolismo
11.
Parasitol Res ; 117(4): 1147-1158, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29470711

RESUMO

Chagas disease is an infection caused by the parasite Trypanosoma cruzi that affects millions of people worldwide and is endemic in Latin America. Megacolon is the most frequent complication of the digestive chronic form and happens due to lesions of the enteric nervous system. The neuronal lesions seem to initiate in the acute phase and persist during the chronic phase, albeit the mechanisms involved in this process are still debated. Among the cells of the immune system possibly involved in this pathological process is the mast cell (MC) due to its well-known role in the bi-directional communication between the immune and nervous systems. Using ultrastructural analysis, we found an increased number of degranulated MCs in close proximity to nerve fibers in infected patients when compared with uninfected controls. We also immunostained MCs for the two pro-inflammatory molecules tryptase and chymase, the first being also important in neuronal death. The number of MCs immunostained for tryptase or chymase was increased in patients with megacolon, whereas increased tryptase staining was additionally observed in patients without megacolon. Moreover, we detected the expression of the tryptase receptor PAR2 in neurons of the enteric nervous system, which correlated to the tryptase staining results. Altogether, the data presented herein point to the participation of MCs on the denervation process that occurs in the development of T. cruzi-induced megacolon.


Assuntos
Doença de Chagas/imunologia , Colo/patologia , Sistema Nervoso Entérico/imunologia , Mastócitos/imunologia , Megacolo/patologia , Neuroimunomodulação/fisiologia , Trypanosoma cruzi/imunologia , Idoso , Animais , Doença de Chagas/parasitologia , Quimases/imunologia , Besouros , Colo/parasitologia , Sistema Nervoso Entérico/parasitologia , Feminino , Humanos , Masculino , Megacolo/parasitologia , Pessoa de Meia-Idade , Neurônios/metabolismo , Receptor PAR-2 , Receptores Acoplados a Proteínas G/metabolismo , Triptases/imunologia
12.
J Allergy Clin Immunol ; 142(1): 120-129.e6, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28916188

RESUMO

BACKGROUND: Group B Streptococcus (GBS) or Streptococcus agalactiae are ß-hemolytic gram-positive bacteria that colonize the lower genital tracts of women and are frequently associated with infections during pregnancy. Innate immune defenses are critical for controlling GBS dissemination and systemic infection. Mast cells are resident sentinel cells that come into contact with pathogens early during colonization and infection. OBJECTIVE: We aimed to investigate the contribution of chymase to systemic GBS infection and rates of preterm birth. METHODS: Pharmacologic and genetic approaches using mice deficient in mast cell protease (MCPT) 4, the mouse functional homologue of human chymase, were used. RESULTS: Our studies show that mast cells release a protease with chymotrypsin-like cleavage specificity in response to GBS. Additionally, increased GBS systemic infection and preterm births were observed in MCPT4-deficient mice versus MCPT4-sufficient mice. Furthermore, we observed that proteolytic cleavage of the host extracellular matrix protein fibronectin by peritoneal cell-derived mast cell lysates diminished GBS adherence. Consistent with this observation, the increase in GBS dissemination and preterm births observed in MCPT4-deficient mice was abolished when GBS was deficient in expression of the fibronectin-binding protein SfbA. CONCLUSIONS: Taken together, our results suggest that the protective effect of MCPT4 against GBS dissemination and preterm labor can be attributed in part to MCPT4-mediated proteolysis of fibronectin. Our studies reveal a novel role of mast cells in defense against bacterial infections.


Assuntos
Mastócitos/imunologia , Serina Endopeptidases/imunologia , Infecções Estreptocócicas/imunologia , Animais , Quimases/imunologia , Feminino , Mastócitos/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Gravidez , Complicações Infecciosas na Gravidez/enzimologia , Complicações Infecciosas na Gravidez/imunologia , Nascimento Prematuro/imunologia , Nascimento Prematuro/microbiologia
13.
Fish Shellfish Immunol ; 66: 307-316, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28522421

RESUMO

Clip domain serine proteases (clip-SPs) play critical roles in various immune responses in arthropods, such as hemolymph coagulation, antimicrobial peptide (AMP) synthesis, cell adhesion and melanization. In the present study, we report the molecular and functional characterization of a clip domain serine protease (PtcSP2) from the swimming crab Portunus trituberculatus. The N-terminal clip domain and the C-terminal SP-like domain of PtcSP2 were expressed in Escherichia coli system, and assayed for their activities. Sequence similarity and phylogenetic analysis revealed that PtcSP2 may belong to the chymotrypsin family, which was confirmed by protease activity assay of the recombinant SP-like domain. The clip domain of PtcSP2 exhibited strong antibacterial activity and microbial-binding activity, suggesting the potential role in immune defense and recognition. Knockdown of PtcSP2 by RNA interference could significantly reduce PtcSP2 transcript levels, but neither decrease the total phenoloxidase (PO) activity in crab nor significantly alter the expression levels of serine protease inhibitors PtPLC and PtSerpin. These results indicate that PtcSP2 is not involved in the proPO system. However, suppression of PtcSP2 led to a significant change in the expression of AMP genes PtALFs and PtCrustin but not PtALF5. All these findings suggest that PtcSP2 is a multifunctional chymotrypsin-like serine protease and may participate in crab innate immunity by its antibacterial activity, immune recognition or regulation of AMP expression.


Assuntos
Braquiúros/enzimologia , Quimases/imunologia , Imunidade Inata/genética , Sequência de Aminoácidos , Animais , Peptídeos Catiônicos Antimicrobianos/imunologia , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Braquiúros/classificação , Braquiúros/genética , Braquiúros/imunologia , Catecol Oxidase/genética , Catecol Oxidase/imunologia , Quimases/química , Quimases/genética , Precursores Enzimáticos/genética , Precursores Enzimáticos/imunologia , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/imunologia , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/imunologia , Filogenia , Pichia/crescimento & desenvolvimento , Pichia/imunologia , Alinhamento de Sequência
14.
Sci Rep ; 6: 38352, 2016 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-27922077

RESUMO

Mast cell infiltration of tumour islets represents a survival advantage in non-small cell lung cancer (NSCLC). The phenotype and activation status of these mast cells is unknown. We investigated the mast cell phenotype in terms of protease content (tryptase-only [MCT], tryptase + chymase [MCTC]) and tumour necrosis factor-alpha (TNFα) expression, and extent of degranulation, in NSCLC tumour stroma and islets. Surgically resected tumours from 24 patients with extended survival (ES; mean survival 86.5 months) were compared with 25 patients with poor survival (PS; mean survival 8.0 months) by immunohistochemistry. Both MCT and MCTC in tumour islets were higher in ES (20.0 and 5.6 cells/mm2 respectively) compared to PS patients (0.0 cells/mm2) (p < 0.0001). Both phenotypes expressed TNFα in the islets and stroma. In ES 44% of MCT and 37% of MCTC expressed TNFα in the tumour islets. MCT in the ES stroma were more degranulated than in those with PS (median degranulation index = 2.24 versus 1.73 respectively) (p = 0.0022), and ES islet mast cells (2.24 compared to 1.71, p < 0.0001). Since both MCT and MCTC infiltrating tumour islets in ES NSCLC patients express TNFα, the cytotoxic activity of this cytokine may confer improved survival in these patients. Manipulating mast cell microlocalisation and functional responses in NSCLC may offer a novel approach to the treatment of this disease.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/imunologia , Quimases/genética , Neoplasias Pulmonares/imunologia , Mastócitos/imunologia , Triptases/genética , Fator de Necrose Tumoral alfa/genética , Idoso , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Degranulação Celular , Movimento Celular , Quimases/imunologia , Citotoxicidade Imunológica , Feminino , Expressão Gênica , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Mastócitos/patologia , Pessoa de Meia-Idade , Fenótipo , Análise de Sobrevida , Triptases/imunologia , Fator de Necrose Tumoral alfa/imunologia
15.
Immunity ; 45(6): 1258-1269, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27939674

RESUMO

Programmed death and shedding of epithelial cells is a powerful defense mechanism to reduce bacterial burden during infection but this activity cannot be indiscriminate because of the critical barrier function of the epithelium. We report that during cystitis, shedding of infected bladder epithelial cells (BECs) was preceded by the recruitment of mast cells (MCs) directly underneath the superficial epithelium where they docked and extruded their granules. MCs were responding to interleukin-1ß (IL-1ß) secreted by BECs after inflammasome and caspase-1 signaling. Upon uptake of granule-associated chymase (mouse MC protease 4 [mMCPT4]), BECs underwent caspase-1-associated cytolysis and exfoliation. Thus, infected epithelial cells require a specific cue for cytolysis from recruited sentinel inflammatory cells before shedding.


Assuntos
Quimases/imunologia , Citotoxinas/imunologia , Células Epiteliais/microbiologia , Mastócitos/imunologia , Infecções Urinárias/imunologia , Animais , Degranulação Celular/imunologia , Linhagem Celular , Grânulos Citoplasmáticos/química , Feminino , Imunofluorescência , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
16.
Acta Oncol ; 55(12): 1434-1442, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27355473

RESUMO

BACKGROUND: Inflammatory cells and inflammatory mediators play an important role in colorectal cancer (CRC). Previous studies have shown that CRC patients with increased expression of cysteinyl leukotriene receptor 1 (CysLTR1) have a poorer prognosis, and Cysltr1-/- mice display fewer intestinal polyps. However, the role of mast cells (MCs) in colon cancer progression remains unclear. The aim of the present study was to explore the relevance of MCs in CRC. MATERIAL AND METHODS: A tissue microarray from 72 CRC patients was stained with MC anti-tryptase and -chymase antibodies. Mouse colon tissue was stained with MC anti-tryptase antibody. Immunohistochemistry was used to identify MCs in patients and mice. RESULTS: Patient colon cancer tissue had in comparison with normal colon tissue a reduced number of MCs, predominantly of chymase-positive cells. Further analysis revealed that patients with a relative high MCD in their cancer tissues showed significantly longer overall survival compared to those with a low MCD [hazard ratio (HR) 0.539; 95% confidence interval (CI), 0.302-0.961]. Similar results were observed in subgroups of patients with either no distant metastasis (p = 0.004), or <75 years (p = 0.015) at time of diagnosis. Multivariate Cox analysis showed that MCD independently correlated with reduced risk of death in colon cancer patients (HR 0.380; 95% CI 0.202-0.713). Additionally, a negative correlation was found between cytoplasmic CysLTR1 expression and number of MCs. In agreement, in the CAC mouse model, Cysltr1-/- mice showed significantly higher MCs in their polyp/tumor areas compared with wild-type mice. CONCLUSION: A high MCD in cancer tissue correlated with longer patient survival independently from other risk factors for CRC. The concept that MCs have an anti-tumor effect in CRC is further supported by the findings of a negative correlation with CysLTR1 expression in patients and a high MCD in colon polyps/tumors from CysLTR1-/- mice.


Assuntos
Biomarcadores Tumorais/análise , Colite/complicações , Neoplasias do Colo/mortalidade , Neoplasias Colorretais/mortalidade , Mastócitos/patologia , Receptores de Leucotrienos/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Casos e Controles , Quimases/imunologia , Colite/induzido quimicamente , Neoplasias do Colo/etiologia , Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Masculino , Mastócitos/enzimologia , Mastócitos/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Análise Serial de Tecidos , Triptases/imunologia
17.
Ross Fiziol Zh Im I M Sechenova ; 102(7): 825-32, 2016 Jul.
Artigo em Russo | MEDLINE | ID: mdl-30193050

RESUMO

Effect of mast cell degranulation blockade on the inflammatory response and character of the lung tissue structure-functional changes were evaluated in the chronic obstructive pulmonary disease model produced in rats by 60-day intermittent exposure to nitrogen dioxide. The membrane stabilizer sodium cromoglicate was used to blockade of mast cell degranulation. Lung tissue sections were stained with toluidine blue to identify mast cells. Bronchoalveolar lavage fluid (BALF) cytogram was determined. The levels of mast cell tryptase and chymase, proinflammatory cytokine TNF-α, surfactant protein B were measured in BALF. Suppression of mast cell degranulation prevented the release of proteases in the bronchoalveolar space and reduced activity of the inflammatory process. The influx of inflammatory cells and TNF-α concentration decreased. There was no interstitial inflammatory infiltration. Bronchoalveolar epithelium structure was recovered that is the basis of its functional usefulness. The results confirm the active involvement of mast cells in the development of the inflammatory process in obstructive pulmonary diseases and allow us to consider them as a possible therapeutic target.


Assuntos
Anti-Inflamatórios/farmacologia , Degranulação Celular/efeitos dos fármacos , Cromolina Sódica/farmacologia , Mastócitos/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Administração por Inalação , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/imunologia , Degranulação Celular/imunologia , Quimases/genética , Quimases/imunologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/patologia , Masculino , Mastócitos/imunologia , Mastócitos/patologia , Dióxido de Nitrogênio/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente , Doença Pulmonar Obstrutiva Crônica/imunologia , Doença Pulmonar Obstrutiva Crônica/patologia , Proteína B Associada a Surfactante Pulmonar/genética , Proteína B Associada a Surfactante Pulmonar/imunologia , Ratos , Ratos Wistar , Triptases/genética , Triptases/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
18.
Clin Exp Allergy ; 46(2): 288-97, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26252943

RESUMO

BACKGROUND: Airway hyperresponsiveness (AHR) to inhaled mannitol is associated with indirect markers of mast cell activation and eosinophilic airway inflammation. It is unknown how AHR to mannitol relates to mast cell phenotype, mast cell function and measures of eosinophilic inflammation in airway tissue. We compared the number and phenotype of mast cells, mRNA expression of mast cell-associated genes and number of eosinophils in airway tissue of subjects with asthma and healthy controls in relation to AHR to mannitol. METHODS: Airway hyperresponsiveness to inhaled mannitol was measured in 23 non-smoking, corticosteroid-free asthmatic individuals and 10 healthy controls. Mast cells and eosinophils were identified in mucosal biopsies from all participants. Mast cells were divided into phenotypes based on the presence of chymase. mRNA expression of mast cell-associated genes was measured by real-time PCR. RESULTS: The proportion of submucosal MCTC was higher in asthmatic individuals with AHR to mannitol compared with asthmatic individuals without AHR (median: 40.3% vs. 18.7%, P = 0.03). Increased submucosal MCTC numbers were associated with increased levels of mRNA for thymic stromal lymphopoietin (TSLP) and CPA3 in asthmatics. Reactivity to mannitol correlated significantly with eosinophils in submucosa (r(s): 0.56, P = 0.01). CONCLUSION: Airway hyperresponsiveness to inhaled mannitol is associated with an altered submucosal mast cell profile in asthmatic individuals. This mast cell profile is associated with increased levels of TSLP and CPA3. The degree of AHR to mannitol is correlated with the degree of eosinophilic inflammation in the airway submucosa.


Assuntos
Asma/imunologia , Hiper-Reatividade Brônquica/imunologia , Eosinófilos/imunologia , Inflamação/imunologia , Mastócitos/imunologia , Adulto , Carboxipeptidases A/biossíntese , Carboxipeptidases A/imunologia , Quimases/imunologia , Estudos Transversais , Citocinas/biossíntese , Citocinas/imunologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Manitol/imunologia , Manitol/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Testes de Função Respiratória/métodos , Mucosa Respiratória/imunologia , Transcriptoma , Adulto Jovem , Linfopoietina do Estroma do Timo
19.
J Ethnopharmacol ; 175: 21-9, 2015 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-26342520

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Turmeric (Curcuma longa) has traditionally been used to treat pain, fever, allergic and inflammatory diseases such as bronchitis, arthritis, and dermatitis. In particular, turmeric and its active component, curcumin, were effective in ameliorating immune disorders including allergies. However, the effects of turmeric and curcumin have not yet been tested on food allergies. MATERIALS AND METHODS: Mice were immunized with intraperitoneal ovalbumin (OVA) and alum. The mice were orally challenged with 50mg OVA, and treated with turmeric extract (100mg/kg), curcumin (3mg/kg or 30 mg/kg) for 16 days. Food allergy symptoms including decreased rectal temperature, diarrhea, and anaphylaxis were evaluated. In addition, cytokines, immunoglobulins, and mouse mast cell protease-1 (mMCP-1) were evaluated using ELISA. RESULTS: Turmeric significantly attenuated food allergy symptoms (decreased rectal temperature and anaphylactic response) induced by OVA, but curcumin showed weak improvement. Turmeric also inhibited IgE, IgG1, and mMCP-1 levels increased by OVA. Turmeric reduced type 2 helper cell (Th2)-related cytokines and enhanced a Th1-related cytokine. Turmeric ameliorated OVA-induced food allergy by maintaining Th1/Th2 balance. Furthermore, turmeric was confirmed anti-allergic effect through promoting Th1 responses on Th2-dominant immune responses in immunized mice. CONCLUSION: Turmeric significantly ameliorated food allergic symptoms in a mouse model of food allergy. The turmeric as an anti-allergic agent showed immune regulatory effects through maintaining Th1/Th2 immune balance, whereas curcumin appeared immune suppressive effects. Therefore, we suggest that administration of turmeric including various components may be useful to ameliorate Th2-mediated allergic disorders such as food allergy, atopic dermatitis, and asthma.


Assuntos
Anafilaxia/tratamento farmacológico , Hipersensibilidade Alimentar/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Células Th1/efeitos dos fármacos , Células Th2/efeitos dos fármacos , Alérgenos/imunologia , Anafilaxia/sangue , Anafilaxia/imunologia , Animais , Quimases/sangue , Quimases/imunologia , Curcuma , Curcumina/farmacologia , Curcumina/uso terapêutico , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Hipersensibilidade Alimentar/sangue , Hipersensibilidade Alimentar/imunologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Fitoterapia , Extratos Vegetais/farmacologia , Células Th1/imunologia , Células Th2/imunologia
20.
Melanoma Res ; 25(6): 479-85, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26317168

RESUMO

The role of mast cells in cutaneous melanoma remains unclear. Tryptase and chymase are serine proteinases and major proteins in mast cell secretory granules. Therefore, this study aimed to investigate the presence of tryptase and chymase mast cells in benign and malignant cutaneous melanocytic lesions and in lymph node metastases of melanomas. The presence of positively stained mast cells was correlated with clinicopathological characteristics in invasive melanomas. Paraffin-embedded sections of 28 benign (13 intradermal, 10 compound, and five junctional nevi) and 26 dysplastic nevi, 15 in-situ melanomas, 36 superficially (pT1, Breslow's thickness<1 mm), and 49 deeply (pT4, Breslow's thickness>4 mm) invasive melanomas and 30 lymph node metastases were immunohistochemically stained for mast cell tryptase and chymase, and immunopositive cells were counted using the hotspot counting method. The mean count of tryptase and chymase mast cells was lower in invasive melanomas compared with in-situ melanomas and dysplastic and benign nevi. In deeply invasive melanomas, the difference was statistically significant compared with dysplastic nevi (P=0.003 for tryptase and P=0.009 for chymase) and in-situ melanomas (0.043 for tryptase). Low numbers of tryptase mast cells were associated with poor overall survival (P=0.031) in deeply invasive melanomas and with a more advanced stage (T1b, P=0.008) in superficially invasive melanomas. Low numbers of chymase mast cells were associated with microsatellites (P=0.017) in deeply invasive melanomas. The results suggest that these serine proteinases of mast cells may be protective in the pathogenesis of melanoma.


Assuntos
Mastócitos/imunologia , Melanoma/imunologia , Melanoma/patologia , Neoplasias Cutâneas/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimases/biossíntese , Quimases/imunologia , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática/imunologia , Metástase Linfática/patologia , Masculino , Mastócitos/enzimologia , Melanoma/mortalidade , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Triptases/biossíntese , Triptases/imunologia , Adulto Jovem
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