RESUMO
Regulatory T cells (Treg cells) maintain host self-tolerance but are a major barrier to effective cancer immunotherapy. Treg cells subvert beneficial anti-tumor immunity by modulating inhibitory receptor expression on tumor-infiltrating lymphocytes (TILs); however, the underlying mediators and mechanisms have remained elusive. Here, we found that the cytokines IL-10 and IL-35 (Ebi3-IL-12α heterodimer) were divergently expressed by Treg cell subpopulations in the tumor microenvironment (TME) and cooperatively promoted intratumoral T cell exhaustion by modulating several inhibitory receptor expression and exhaustion-associated transcriptomic signature of CD8+ TILs. While expression of BLIMP1 (encoded by Prdm1) was a common target, IL-10 and IL-35 differentially affected effector T cell versus memory T cell fates, respectively, highlighting their differential, partially overlapping but non-redundant regulation of anti-tumor immunity. Our results reveal previously unappreciated cooperative roles for Treg cell-derived IL-10 and IL-35 in promoting BLIMP1-dependent exhaustion of CD8+ TILs that limits effective anti-tumor immunity.
Assuntos
Imunidade Celular , Interleucina-10/metabolismo , Interleucinas/metabolismo , Neoplasias/imunologia , Neoplasias/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Transferência Adotiva , Animais , Citocinas/genética , Citocinas/metabolismo , Perfilação da Expressão Gênica , Humanos , Melanoma Experimental , Camundongos , Neoplasias/patologia , Transdução de Sinais , TranscriptomaRESUMO
The pathophysiology of chronic obstructive pulmonary disease (COPD) and the undisputed role of innate immune cells in this condition have dominated the field in the basic research arena for many years. Recently, however, compelling data suggesting that adaptive immune cells may also contribute to the progressive nature of lung destruction associated with COPD in smokers have gained considerable attention. The histopathological changes in the lungs of smokers can be limited to the large or small airways, but alveolar loss leading to emphysema, which occurs in some individuals, remains its most significant and irreversible outcome. Critically, however, the question of why emphysema progresses in a subset of former smokers remained a mystery for many years. The recognition of activated and organized tertiary T- and B-lymphoid aggregates in emphysematous lungs provided the first clue that adaptive immune cells may play a crucial role in COPD pathophysiology. Based on these findings from human translational studies, experimental animal models of emphysema were used to determine the mechanisms through which smoke exposure initiates and orchestrates adaptive autoreactive inflammation in the lungs. These models have revealed that T helper (Th)1 and Th17 subsets promote a positive feedback loop that activates innate immune cells, confirming their role in emphysema pathogenesis. Results from genetic studies and immune-based discoveries have further provided strong evidence for autoimmunity induction in smokers with emphysema. These new findings offer a novel opportunity to explore the mechanisms underlying the inflammatory landscape in the COPD lung and offer insights for development of precision-based treatment to halt lung destruction.
Assuntos
Enfisema , Doença Pulmonar Obstrutiva Crônica , Enfisema Pulmonar , Animais , Humanos , Enfisema Pulmonar/etiologia , Enfisema Pulmonar/patologia , Enfisema/complicações , Enfisema/patologia , Pulmão , Imunidade Adaptativa , Modelos TeóricosRESUMO
Fungal airway infection (airway mycosis) is an important cause of allergic airway diseases such as asthma, but the mechanisms by which fungi trigger asthmatic reactions are poorly understood. Here, we leverage wild-type and mutant Candida albicans to determine how this common fungus elicits characteristic Th2 and Th17 cell-dependent allergic airway disease in mice. We demonstrate that rather than proteinases that are essential virulence factors for molds, C. albicans instead promoted allergic airway disease through the peptide toxin candidalysin. Candidalysin activated platelets through the Von Willebrand factor (VWF) receptor GP1bα to release the Wnt antagonist Dickkopf-1 (Dkk-1) to drive Th2 and Th17 cell responses that correlated with reduced lung fungal burdens. Platelets simultaneously precluded lethal pulmonary hemorrhage resulting from fungal lung invasion. Thus, in addition to hemostasis, platelets promoted protection against C. albicans airway mycosis through an antifungal pathway involving candidalysin, GP1bα, and Dkk-1 that promotes Th2 and Th17 responses.
Assuntos
Plaquetas/imunologia , Candida albicans/fisiologia , Candidíase/complicações , Candidíase/imunologia , Suscetibilidade a Doenças , Interações Hospedeiro-Patógeno/imunologia , Hipersensibilidade/complicações , Hipersensibilidade/imunologia , Subpopulações de Linfócitos T/imunologia , Plaquetas/metabolismo , Hipersensibilidade/metabolismo , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos T/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Células Th2/imunologia , Células Th2/metabolismoRESUMO
Smoking-related emphysema is a chronic inflammatory disease driven by the T(H)17 subset of helper T cells through molecular mechanisms that remain obscure. Here we explored the role of the microRNA miR-22 in emphysema. We found that miR-22 was upregulated in lung myeloid dendritic cells (mDCs) of smokers with emphysema and antigen-presenting cells (APCs) of mice exposed to smoke or nanoparticulate carbon black (nCB) through a mechanism that involved the transcription factor NF-κB. Mice deficient in miR-22, but not wild-type mice, showed attenuated T(H)17 responses and failed to develop emphysema after exposure to smoke or nCB. We further found that miR-22 controlled the activation of APCs and T(H)17 responses through the activation of AP-1 transcription factor complexes and the histone deacetylase HDAC4. Thus, miR-22 is a critical regulator of both emphysema and T(H)17 responses.
Assuntos
Enfisema/etiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Células Th17/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Enfisema/imunologia , Enfisema/metabolismo , Histona Desacetilases/metabolismo , Humanos , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Fumar/efeitos adversos , Fuligem/toxicidade , Células Th17/metabolismo , Fator de Transcrição AP-1/metabolismoRESUMO
Transcription factors of the STAT family are critical in the cytokine-mediated functional differentiation of CD4(+) helper T cells. Signaling inhibitors of the SOCS family negatively regulate the activation of STAT proteins; however, their roles in the differentiation and function of helper T cells are not well understood. Here we found that the SOCS protein CIS, which was substantially induced by interleukin 4 (IL-4), negatively regulated the activation of STAT3, STAT5 and STAT6 in T cells. CIS-deficient mice spontaneously developed airway inflammation, and CIS deficiency in T cells led to greater susceptibility to experimental allergic asthma. CIS-deficient T cells showed enhanced differentiation into the TH2 and TH9 subsets of helper T cells. STAT5 and STAT6 regulated IL-9 expression by directly binding to the Il9 promoter. Our data thus demonstrate a critical role for CIS in controlling the proallergic generation of helper T cells.
Assuntos
Asma/imunologia , Inflamação/imunologia , Fatores de Transcrição STAT/imunologia , Proteínas Supressoras da Sinalização de Citocina/imunologia , Linfócitos T Reguladores/imunologia , Animais , Diferenciação Celular/imunologia , Histocitoquímica , Immunoblotting , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , RNA/química , RNA/genética , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Proteínas Supressoras da Sinalização de Citocina/genéticaRESUMO
BACKGROUND: In a gene expression analysis comparing sinus mucosa samples from allergic fungal rhinosinusitis (AFRS) patients with samples from non-AFRS chronic rhinosinusitis with nasal polyp (CRSwNP) patients, the antimicrobial peptide (AMP) histatin 1 (HTN1) was found to be the most differentially downregulated gene in AFRS. OBJECTIVE: We sought to identify the molecular etiology of the downregulated expression of HTN1. METHODS: We used RT-PCR to compare the expression of AMPs and a fungistasis assay to evaluate the antifungal activity of sinus secretions. Using flow cytometry, we characterized the presence of TH17/TH22 cells and signal transducer and activator of transcription (STAT) signaling from AFRS patients, non-AFRS CRSwNP patients, and healthy controls. RESULTS: We confirmed decreased expression of AMPs in AFRS sinus mucosa with concordant decrease in antifungal activity in sinus secretions. IL-22 and IL-22-producing T cells were deficient within sinus mucosa of AFRS patients. In vitro studies demonstrated a defect in IL-6/STAT3 signaling critical for TH17/TH22 differentiation. Epithelial cells from AFRS patients could express AMPs when stimulated with exogenous IL-22/IL-17 and circulating TH17 cell abundance was normal. CONCLUSIONS: Similar to other hyper-IgE syndromes, but distinct from CRSwNP, AFRS patients express a defect in STAT3 activation limited to IL-6-dependent STAT3 phosphorylation that is critical for TH17/TH22 differentiation. This defect leads to a local deficiency of IL-17/IL-22 cytokines and deficient AMP expression within diseased sinus mucosa of AFRS patients. Our findings support evaluation of therapeutic approaches that enhance airway AMP production in AFRS.
RESUMO
Microbial infections of the brain can lead to dementia, and for many decades microbial infections have been implicated in Alzheimer's disease (AD) pathology. However, a causal role for infection in AD remains contentious, and the lack of standardized detection methodologies has led to inconsistent detection/identification of microbes in AD brains. There is a need for a consensus methodology; the Alzheimer's Pathobiome Initiative aims to perform comparative molecular analyses of microbes in post mortem brains versus cerebrospinal fluid, blood, olfactory neuroepithelium, oral/nasopharyngeal tissue, bronchoalveolar, urinary, and gut/stool samples. Diverse extraction methodologies, polymerase chain reaction and sequencing techniques, and bioinformatic tools will be evaluated, in addition to direct microbial culture and metabolomic techniques. The goal is to provide a roadmap for detecting infectious agents in patients with mild cognitive impairment or AD. Positive findings would then prompt tailoring of antimicrobial treatments that might attenuate or remit mounting clinical deficits in a subset of patients.
Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/patologia , Consenso , Disfunção Cognitiva/patologia , Encéfalo/patologiaRESUMO
Environmental fungi are etiologically related to chronic rhinosinusitis (CRS) with airway mycosis, but their infectious role remains uncertain, in part because of potentially inadequate methods of disease quantitation. Our objective was to determine objective radiographic and symptomatic outcomes of oral antifungal therapy in adult patients with CRS and airway mycosis by using computer-assisted analysis. We conducted a retrospective study of 65 patients with CRS and culture-proven airway mycosis in a single-center referral-based academic practice, comparing paired sinus computed tomography (CT) scans and symptom scores prior to and during chronic oral antifungal therapy using computer-assisted analysis of sino-mucosal area (CAASMA). A comparator group received standard therapy without antifungals. Administration of antifungals was associated with significantly reduced sinus mucosal thickening as assessed by CAASMA (-6.85% absolute reduction; 95% confidence interval [CI], -11.8283 to -1.8717; P < 0.005), but not by Lund-Mackay score. In contrast, standard care alone was linked by CAASMA to enhanced mucosal thickening (4.14% absolute increase; 95% CI, -1.8066 to 10.0866; P < 0.005). Thirty of the 41 antifungal-treated patients (73%) showed decreased sinus mucosal burdens, while only 21 patients (43%) receiving standard therapy showed improved imaging (odds ratio [OR], 11.65; 95% CI, 3.2 to 42.2; P < 0.05). Nineteen patients (50%) noted improved symptoms at the time of a follow-up CT scan, while only 8 patients (20%) on standard therapy improved (OR, 6.21; 95% CI, 1.7 to 22.7; P < 0.05). These retrospective findings indicate that oral antifungals can reduce mucosal thickening and improve symptoms in CRS with airway mycosis. Randomized clinical trials are warranted to verify these findings.
Assuntos
Antifúngicos , Rinite , Adulto , Antifúngicos/uso terapêutico , Doença Crônica , Computadores , Humanos , Estudos Retrospectivos , Rinite/tratamento farmacológico , Índice de Gravidade de DoençaRESUMO
The innate immune response of airway epithelial cells to airborne allergens initiates the development of T cell responses that are central to allergic inflammation. Although proteinase allergens induce the expression of interleukin 25, we show here that epithelial matrix metalloproteinase 7 (MMP7) was expressed during asthma and was required for the maximum activity of interleukin 25 in promoting the differentiation of T helper type 2 cells. Allergen-challenged Mmp7(-/-) mice had less airway hyper-reactivity and production of allergic inflammatory cytokines and higher expression of retinal dehydrogenase 1. Inhibition of retinal dehydrogenase 1 restored the asthma phenotype of Mmp7(-/-) mice and inhibited the responses of lung regulatory T cells, whereas exogenous administration of retinoic acid attenuated the asthma phenotype. Thus, MMP7 coordinates allergic lung inflammation by activating interleukin 25 while simultaneously inhibiting retinoid-dependent development of regulatory T cells.
Assuntos
Asma/metabolismo , Interleucinas/metabolismo , Metaloproteinase 7 da Matriz/metabolismo , Mucosa Respiratória/metabolismo , Tretinoína/metabolismo , Alérgenos/imunologia , Animais , Asma/imunologia , Asma/patologia , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Diferenciação Celular/imunologia , Cromatografia Líquida de Alta Pressão , Citocinas/biossíntese , Citocinas/imunologia , Modelos Animais de Doenças , Eletroforese em Gel Bidimensional , Humanos , Imuno-Histoquímica , Interleucinas/imunologia , Ativação Linfocitária/imunologia , Metaloproteinase 7 da Matriz/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteômica , Mucosa Respiratória/imunologia , Retinal Desidrogenase/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Th2/citologia , Células Th2/imunologia , Tretinoína/imunologiaRESUMO
BACKGROUND: Inhalation of fungal spores is a strong risk factor for severe asthma and experimentally leads to development of airway mycosis and asthma-like disease in mice. However, in addition to fungal spores, humans are simultaneously exposed to other inflammatory agents such as lipopolysaccharide (LPS), with uncertain relevance to disease expression. To determine how high dose inhalation of LPS influences the expression of allergic airway disease induced by the allergenic mold Aspergillus niger (A. niger). METHODS: C57BL/6J mice were intranasally challenged with the viable spores of A. niger with and without 1 µg of LPS over two weeks. Changes in airway hyperreactivity, airway and lung inflammatory cell recruitment, antigen-specific immunoglobulins, and histopathology were determined. RESULTS: In comparison to mice challenged only with A. niger, addition of LPS (1 µg) to A. niger abrogated airway hyperresponsiveness and strongly attenuated airway eosinophilia, PAS+ goblet cells and TH2 responses while enhancing TH1 and TH17 cell recruitment to lung. Addition of LPS resulted in more severe, diffuse lung inflammation with scattered, loosely-formed parenchymal granulomas, but failed to alter fungus-induced IgE and IgG antibodies. CONCLUSIONS: In contrast to the strongly allergic lung phenotype induced by fungal spores alone, addition of a relatively high dose of LPS abrogates asthma-like features, replacing them with a phenotype more consistent with acute hypersensitivity pneumonitis (HP). These findings extend the already established link between airway mycosis and asthma to HP and describe a robust model for further dissecting the pathophysiology of HP.
Assuntos
Alveolite Alérgica Extrínseca/microbiologia , Aspergillus niger/patogenicidade , Hiper-Reatividade Brônquica/microbiologia , Lipopolissacarídeos , Pulmão/microbiologia , Aspergilose Pulmonar/microbiologia , Esporos Fúngicos/patogenicidade , Alveolite Alérgica Extrínseca/induzido quimicamente , Alveolite Alérgica Extrínseca/imunologia , Alveolite Alérgica Extrínseca/fisiopatologia , Animais , Aspergillus niger/imunologia , Hiper-Reatividade Brônquica/induzido quimicamente , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/fisiopatologia , Broncoconstrição , Modelos Animais de Doenças , Eosinófilos/imunologia , Exposição por Inalação , Pulmão/imunologia , Pulmão/fisiopatologia , Camundongos Endogâmicos C57BL , Aspergilose Pulmonar/imunologia , Aspergilose Pulmonar/fisiopatologia , Esporos Fúngicos/imunologia , Linfócitos T Auxiliares-Indutores/imunologiaRESUMO
Loss of immune tolerance to self-antigens can promote chronic inflammation and disrupt the normal function of multiple organs, including the lungs. Degradation of elastin, a highly insoluble protein and a significant component of the lung structural matrix, generates proinflammatory molecules. Elastin fragments (EFs) have been detected in the serum of smokers with emphysema, and elastin-specific T cells have also been detected in the peripheral blood of smokers with emphysema. However, an animal model that could recapitulate T cell-specific autoimmune responses by initiating and sustaining inflammation in the lungs is lacking. In this study, we report an animal model of autoimmune emphysema mediated by the loss of tolerance to elastin. Mice immunized with a combination of human EFs plus rat EFs but not mouse EFs showed increased infiltration of innate and adaptive immune cells to the lungs and developed emphysema. We cloned and expanded mouse elastin-specific CD4+ T cells from the lung and spleen of immunized mice. Finally, we identified TCR sequences from the autoreactive T cell clones, suggesting possible pathogenic TCRs that can cause loss of immune tolerance against elastin. This new autoimmune model of emphysema provides a useful tool to examine the immunological factors that promote loss of immune tolerance to self.
Assuntos
Autoimunidade/imunologia , Elastina/imunologia , Pulmão/imunologia , Enfisema Pulmonar/imunologia , Imunidade Adaptativa/imunologia , Animais , Linhagem Celular , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Tolerância Imunológica/imunologia , Imunidade Inata/imunologia , Inflamação/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Doença Pulmonar Obstrutiva Crônica/imunologia , Fumar/imunologiaRESUMO
Proteinases are essential drivers of allergic airway disease and innate antifungal immunity in part through their ability cleave the clotting factor fibrinogen (FBG) into fibrinogen cleavage products (FCPs) that signal through Toll-like receptor 4 (TLR4). However, the mechanism by which FCPs engage TLR4 remains unknown. Here, we show that the proteinases from Aspergillus melleus (PAM) and other allergenic organisms rapidly hydrolyze FBG to yield relatively few FCPs that drive distinct antifungal mechanisms through TLR4. Functional FCPs, termed cryptokines, were characterized by rapid loss of the FBG α chain with substantial preservation of the ß and γ chains, including a γ chain sequence (Fibγ390-396) that binds the integrin Mac-1 (CD11b/CD18). PAM-derived cryptokines could be generated from multiple FBG domains, and the ability of cryptokines to induce fungistasis in vitro and innate allergic airway disease in vivo strongly depended on both Mac-1 and the Mac-1-binding domain of FBG (Fibγ390-396). Our findings illustrate the essential concept of proteinase-activated immune responses and for the first time link Mac-1, cryptokines, and TLR4 to innate antifungal immunity and allergic airway disease.
Assuntos
Aspergillus/imunologia , Antígeno CD11b/metabolismo , Fibrinogênio/metabolismo , Proteínas Fúngicas/metabolismo , Imunidade Inata , Peptídeo Hidrolases/metabolismo , Animais , Aspergillus/enzimologia , Antígeno CD11b/deficiência , Antígeno CD11b/genética , Modelos Animais de Doenças , Fibrinogênio/química , Hipersensibilidade/imunologia , Hipersensibilidade/metabolismo , Hipersensibilidade/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ligação Proteica , Domínios Proteicos , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Receptor 4 Toll-Like/metabolismoRESUMO
Asthma is a chronic inflammatory disease of the lungs and airways and one of the most burdensome of all chronic maladies. Previous studies have established that expression of experimental and human asthma requires the IL-4/IL-13/IL-4 receptor α (IL-4Rα) signaling pathway, which activates the transcription factor STAT6. However, no small molecules targeting this important pathway are currently in clinical development. To this end, using a preclinical asthma model, we sought to develop and test a small-molecule inhibitor of the Src homology 2 domains in mouse and human STAT6. We previously developed multiple peptidomimetic compounds on the basis of blocking the docking site of STAT6 to IL-4Rα and phosphorylation of Tyr641 in STAT6. Here, we expanded the scope of our initial in vitro structure-activity relationship studies to include central and C-terminal analogs of these peptides to develop a lead compound, PM-43I. Conducting initial dose range, toxicity, and pharmacokinetic experiments with PM-43I, we found that it potently inhibits both STAT5- and STAT6-dependent allergic airway disease in mice. Moreover, PM-43I reversed preexisting allergic airway disease in mice with a minimum ED50 of 0.25 µg/kg. Of note, PM-43I was efficiently cleared through the kidneys with no long-term toxicity. We conclude that PM-43I represents the first of a class of small molecules that may be suitable for further clinical development against asthma.
Assuntos
Asma/tratamento farmacológico , Terapia de Alvo Molecular , Fator de Transcrição STAT5/química , Fator de Transcrição STAT5/metabolismo , Fator de Transcrição STAT6/química , Fator de Transcrição STAT6/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Asma/imunologia , Asma/metabolismo , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/metabolismo , Camundongos , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/uso terapêutico , Relação Estrutura-Atividade , Domínios de Homologia de srcRESUMO
BACKGROUND: Inhaled protease allergens preferentially trigger TH2-mediated inflammation in allergic asthma. The role of dendritic cells (DCs) on induction of TH2 cell responses in allergic asthma has been well documented; however, the mechanism by which protease allergens induce TH2-favorable DCs in the airway remains unclear. OBJECTIVE: We sought to determine a subset of DCs responsible for TH2 cell responses in allergic asthma and the mechanism by which protease allergens induce the DC subset in the airway. METHODS: Mice were challenged intranasally with protease allergens or fibrinogen cleavage products (FCPs) to induce allergic airway inflammation. DCs isolated from mediastinal lymph nodes were analyzed for surface phenotype and T-cell stimulatory function. Anti-Thy1.2 and Mas-TRECK mice were used to deplete innate lymphoid cells and mast cells, respectively. Adoptive cell transfer, bone marrow DC culture, anti-IL-13, and Toll-like receptor (TLR) 4-deficient mice were used for further mechanistic studies. RESULTS: Protease allergens induced a remarkable accumulation of TH2-favorable programmed cell death 1 ligand 2 (PD-L2)+ DCs in mediastinal lymph nodes, which was significantly abolished in mice depleted of mast cells and, to a lesser extent, innate lymphoid cells. Mechanistically, FCPs generated by protease allergens triggered IL-13 production from wild-type mast cells but not from TLR4-deficient mast cells, which resulted in an increase in the number of PD-L2+ DCs. Intranasal administration of FCPs induced an increase in numbers of PD-L2+ DCs in the airway, which was significantly abolished in TLR4- and mast cell-deficient mice. Injection of IL-13 restored the PD-L2+ DC population in mice lacking mast cells. CONCLUSION: Our findings unveil the "protease-FCP-TLR4-mast cell-IL-13" axis as a molecular mechanism for generation of TH2-favorable PD-L2+ DCs in allergic asthma and suggest that targeting the PD-L2+ DC pathway might be effective in suppressing allergic T-cell responses in the airway.
Assuntos
Asma/imunologia , Células Dendríticas/imunologia , Fibrinogênio/metabolismo , Hipersensibilidade/imunologia , Fragmentos de Peptídeos/metabolismo , Peptídeo Hidrolases/metabolismo , Receptor 4 Toll-Like/metabolismo , Alérgenos/imunologia , Animais , Diferenciação Celular , Modelos Animais de Doenças , Fibrinogênio/imunologia , Humanos , Imunidade Inata , Interleucina-13/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fragmentos de Peptídeos/imunologia , Proteína 2 Ligante de Morte Celular Programada 1/metabolismo , Células Th2/imunologia , Receptor 4 Toll-Like/genéticaRESUMO
Ascaris lumbricoides (roundworm) is the most common helminth infection globally and a cause of lifelong morbidity that may include allergic airway disease, an asthma phenotype. We hypothesize that Ascaris larval migration through the lungs leads to persistent airway hyperresponsiveness (AHR) and type 2 inflammatory lung pathology despite resolution of infection that resembles allergic airway disease. Mice were infected with Ascaris by oral gavage. Lung AHR was measured by plethysmography and histopathology with hematoxylin and eosin (H&E) and periodic acid-Schiff (PAS) stains, and cytokine concentrations were measured by using Luminex Magpix. Ascaris-infected mice were compared to controls or mice with allergic airway disease induced by ovalbumin (OVA) sensitization and challenge (OVA/OVA). Ascaris-infected mice developed profound AHR starting at day 8 postinfection (p.i.), peaking at day 12 p.i. and persisting through day 21 p.i., despite resolution of infection, which was significantly increased compared to controls and OVA/OVA mice. Ascaris-infected mice had a robust type 2 cytokine response in both the bronchoalveolar lavage (BAL) fluid and lung tissue, similar to that of the OVA/OVA mice, including interleukin-4 (IL-4) (P < 0.01 and P < 0.01, respectively), IL-5 (P < 0.001 and P < 0.001), and IL-13 (P < 0.001 and P < 0.01), compared to controls. By histopathology, Ascaris-infected mice demonstrated early airway remodeling similar to, but more profound than, that in OVA/OVA mice. We found that Ascaris larval migration causes significant pulmonary damage, including AHR and type 2 inflammatory lung pathology that resembles an extreme form of allergic airway disease. Our findings indicate that ascariasis may be an important cause of allergic airway disease in regions of endemicity.
Assuntos
Ascaríase/fisiopatologia , Hipersensibilidade/parasitologia , Pulmão/patologia , Hipersensibilidade Respiratória/parasitologia , Animais , Ascaríase/imunologia , Ascaris/patogenicidade , Líquido da Lavagem Broncoalveolar/imunologia , Modelos Animais de Doenças , Feminino , Interleucina-13/imunologia , Interleucina-4/imunologia , Interleucina-5/imunologia , Larva/patogenicidade , Pulmão/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Células Th2/imunologiaRESUMO
Allergic asthma is a heterogeneous disorder that defies a unanimously acceptable definition, but is generally recognized through its highly characteristic clinical expression of dyspnea and cough accompanied by clinical data that document reversible or exaggerated airway constriction and obstruction. The generally rising prevalence of asthma in highly industrialized societies despite significant therapeutic advances suggests that the fundamental cause(s) of asthma remain poorly understood. Detailed analyses of both the indoor (built) and outdoor environments continue to support the concept that not only inhaled particulates, especially carbon-based particulate pollution, pollens, and fungal elements, but also many noxious gases and chemicals, especially biologically derived byproducts such as proteinases, are essential to asthma pathogenesis. Phthalates, another common class of chemical pollutant found in the built environment, are emerging as potentially important mediators or attenuators of asthma. Other biological products such as endotoxin have also been confirmed to be protective in both the indoor and outdoor contexts. Proasthmatic factors are believed to activate, and in some instances initiate, pathologic inflammatory cascades through complex interactions with pattern recognition receptors (PRRs) expressed on many cell types, but especially airway epithelial cells. PRRs initiate the release of proallergic cytokines such as interleukin (IL)-33, IL-25, and others that coordinate activation of innate lymphoid cells type 2 (ILC2), T helper type 2 cells, and immunoglobulin E-secreting B cells that together promote additional inflammation and the major airway remodeling events (airway hyperresponsiveness, mucus hypersecretion) that promote airway obstruction. Proteinases, with airway fungi and viruses being potentially important sources, are emerging as critically important initiators of these inflammatory cascades in part through their effects on clotting factors such as fibrinogen. Recent clinical trials have demonstrated that targeting inflammatory pathways orchestrated through IL-4, IL-5, IL-13, and the prostaglandin receptor CRTH2 is potentially highly effective in adult asthma.
Assuntos
Asma/tratamento farmacológico , Asma/fisiopatologia , Inflamação/complicações , Animais , Asma/epidemiologia , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Exposição Ambiental/efeitos adversos , Humanos , Inflamação/microbiologia , Sistema Respiratório/microbiologia , Células Th2/efeitos dos fármacos , Células Th2/imunologiaRESUMO
OBJECTIVE: Angiogenesis is tightly controlled by growth factors and cytokines in pathophysiological settings. Interleukin 37 (IL-37) is a newly identified cytokine of the IL-1 family, some members of which are important in inflammation and angiogenesis. However, the function of IL-37 in angiogenesis remains unknown. We aimed to explore the regulatory role of IL-37 in pathological and physiological angiogenesis. APPROACH AND RESULTS: We found that IL-37 was expressed and secreted in endothelial cells and upregulated under hypoxic conditions. IL-37 enhanced endothelial cell proliferation, capillary formation, migration, and vessel sprouting from aortic rings with potency comparable with that of vascular endothelial growth factor. IL-37 activates survival signals including extracellular signal-regulated kinase 1/2 and AKT in endothelial cells. IL-37 promoted vessel growth in implanted Matrigel plug in vivo in a dose-dependent manner with potency comparable with that of basic fibroblast growth factor. In the mouse model of retinal vascular development, neonatal mice administrated with IL-37 displayed increased neovascularization. We demonstrated further that IL-37 promoted pathological angiogenesis in the mouse model of oxygen-induced retinopathy. CONCLUSIONS: Our findings suggest that IL-37 is a novel and potent proangiogenic cytokine with essential role in pathophy siological settings.
Assuntos
Indutores da Angiogênese/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Interleucina-1/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Retiniana/induzido quimicamente , Retinopatia da Prematuridade/induzido quimicamente , Animais , Animais Recém-Nascidos , Hipóxia Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Interleucina-1/metabolismo , Interleucina-1/toxicidade , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Retinopatia da Prematuridade/metabolismo , Retinopatia da Prematuridade/patologia , Fatores de Tempo , TransfecçãoRESUMO
RATIONALE: Cross-sectional studies of T-cell responses to self-antigens correlate with baseline emphysema severity. OBJECTIVES: We investigated whether clinical and/or immunological factors could predict disease progression, such as emphysema, FEV1, and 6-minute-walk distance (6MWD), in former and active smokers in a 5-year prospective study. METHODS: We recruited 224 ever smokers over 40 years of age and with greater than a 15 pack-year smoking history. MEASUREMENTS AND MAIN RESULTS: Repeated spirometry, 6MWD, and peripheral blood T-cell cytokine responses to lung elastin fragments were measured. Baseline and repeat chest computed tomography (CT) scans (34 to 65 mo apart) were used to quantify emphysema progression. Of the 141 ever-smokers with baseline and repeat CT scans, the mean (SD) annual rate of change in percent emphysema was +0.46 (0.92), ranging from -1.8 to +4.1. In multivariable analyses, the rate of emphysema progression was greater in subjects who had lower body mass index (BMI) (+0.15 per 5-unit decrease in BMI; 95% confidence interval, +0.03 to +0.29). In active smokers, increased IFN-γ and IL-6 T-cell responses had a positive association with the annual rate of emphysema progression. Male sex and IL-6 T-cell responses to elastin fragments were significantly associated with annual 6MWD decline, whereas IL-13 was associated with an increase in annual 6MWD. CONCLUSIONS: The rate of emphysema progression quantified by CT scans among ever-smokers was highly variable; clinical factors and biomarkers explained only some of the variability. Aggressive clinical care that targets active smokers with autoreactive T cells and low BMI may temporize progression of emphysema.
Assuntos
Citocinas/imunologia , Enfisema/etiologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Fumar/efeitos adversos , Linfócitos T/imunologia , Análise de Variância , Estudos Transversais , Citocinas/análise , Progressão da Doença , Teste de Esforço , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prognóstico , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Índice de Gravidade de DoençaRESUMO
Allergic asthma is a chronic inflammatory disease of the airways. Of the different lower airway-infiltrating immune cells that participate in asthma, T lymphocytes that produce Th2 cytokines play important roles in pathogenesis. These T cells are mainly fully differentiated CCR7(-) effector memory T (TEM) cells. Targeting TEM cells without affecting CCR7(+) naïve and central memory (TCM) cells has the potential of treating TEM-mediated diseases, such as asthma, without inducing generalized immunosuppression. The voltage-gated KV1.3 potassium channel is a target for preferential inhibition of TEM cells. Here, we investigated the effects of ShK-186, a selective KV1.3 channel blocker, for the treatment of asthma. A significant proportion of T lymphocytes in the lower airways of subjects with asthma expressed high levels of KV1.3 channels. ShK-186 inhibited the allergen-induced activation of peripheral blood T cells from those subjects. Immunization of F344 rats against ovalbumin followed by intranasal challenges with ovalbumin induced airway hyper-reactivity, which was reduced by the administration of ShK-186. ShK-186 also reduced total immune infiltrates in the bronchoalveolar lavage and number of infiltrating lymphocytes, eosinophils, and neutrophils assessed by differential counts. Rats with the ovalbumin-induced model of asthma had elevated levels of the Th2 cytokines IL-4, IL-5, and IL-13 measured by ELISA in their bronchoalveolar lavage fluids. ShK-186 administration reduced levels of IL-4 and IL-5 and induced an increase in the production of IL-10. Finally, ShK-186 inhibited the proliferation of lung-infiltrating ovalbumin-specific T cells. Our results suggest that KV1.3 channels represent effective targets for the treatment of allergic asthma.
Assuntos
Asma/imunologia , Modelos Animais de Doenças , Canal de Potássio Kv1.3/imunologia , Células Th2/imunologia , Adulto , Animais , Asma/metabolismo , Asma/prevenção & controle , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/imunologia , Feminino , Citometria de Fluxo , Humanos , Memória Imunológica/efeitos dos fármacos , Memória Imunológica/imunologia , Interleucina-10/imunologia , Interleucina-10/metabolismo , Interleucina-13/imunologia , Interleucina-13/metabolismo , Interleucina-4/imunologia , Interleucina-4/metabolismo , Interleucina-5/imunologia , Interleucina-5/metabolismo , Canal de Potássio Kv1.3/antagonistas & inibidores , Canal de Potássio Kv1.3/metabolismo , Masculino , Pessoa de Meia-Idade , Ovalbumina/imunologia , Bloqueadores dos Canais de Potássio/imunologia , Bloqueadores dos Canais de Potássio/farmacologia , Proteínas/imunologia , Proteínas/farmacologia , Ratos , Ratos Endogâmicos F344 , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Células Th2/efeitos dos fármacos , Células Th2/metabolismo , Adulto JovemRESUMO
RNA interference mediated through antisense transcripts is a fundamentally important mechanism regulating gene expression that remains incompletely understood. Here, we have used next-generation sequencing to determine from mouse CD4+ T cells the functional implications of antisense transcripts binding to argonaute (AGO) proteins that mediate RNA interference and post-transcriptional gene silencing. This effort identified 90 new microRNAs (miRNAs) and six endogenous hairpin RNA-derived small interfering RNAs (siRNAs) mapping to distinct introns. Unexpectedly, 69 miRNAs were expressed as non-canonical isomiRs as the dominant AGO-binding transcript, with extensive 3' terminal nucleotide modifications. Furthermore, differential expression analysis between AGO1- and AGO2-bound miRNAs suggested preferential binding of isomiRs ending with 3' adenine residues to AGO1 and 3' uridine residues to AGO2. Analysis of the putative targets of all miRNAs suggested a striking preference for regulating transcription and transcription factors with additional evidence of a functional division of labor between AGO proteins in this regard. We further provide evidence that multiple mitochondrial genomic loci serve as the source of endogenous cis-natural antisense transcripts. These findings imply diversity in AGO protein function based on differential miRNA binding and indicate that RNA interference-based gene regulation is more complex than previously recognized.