RESUMEN
Myeloid-derived suppressor cells (MDSC) are immature myeloid cells that accumulate in the tumor microenvironment (TME). MDSCs have been shown to dampen antitumor immune responses and promote tumor growth; however, the mechanisms of MDSC induction and their role in promoting immune suppression in cancer remain poorly understood. Here, we characterized the phenotype and function of monocytic MDSCs (M-MDSC) generated by coculture of human peripheral blood mononuclear cells with SK-MEL-5 cancer cells in vitro. We selected the SK-MEL-5 human melanoma cell line to generate M-MDSCs because these cells form subcutaneous tumors rich in myeloid cells in humanized mice. M-MDSCs generated via SK-MEL-5 coculture expressed low levels of human leukocyte antigen (HLA)-DR, high levels of CD33 and CD11b, and suppressed both CD8+ T-cell proliferation and IFNγ secretion. M-MDSCs also expressed higher levels of immunoglobulin-like transcript 3 (ILT3, also known as LILRB4) and immunoglobulin-like transcript 4 (ILT4, also known as LILRB2) on the cell surface compared with monocytes. Therefore, we investigated how ILT3 targeting could modulate M-MDSC cell function. Treatment with an anti-ILT3 antibody impaired the acquisition of the M-MDSC suppressor phenotype and reduced the capacity of M-MDSCs to cause T-cell suppression. Finally, in combination with anti-programmed cell death protein 1 (PD1), ILT3 blockade enhanced T-cell activation as assessed by IFNγ secretion. IMPLICATIONS: These results suggest that ILT3 expressed on M-MDSCs has a role in inducing immunosuppression in cancer and that antagonism of ILT3 may be useful to reverse the immunosuppressive function of M-MDSCs and enhance the efficacy of immune checkpoint inhibitors.
Asunto(s)
Melanoma/inmunología , Glicoproteínas de Membrana/inmunología , Monocitos/inmunología , Células Supresoras de Origen Mieloide/inmunología , Receptores Inmunológicos/inmunología , Animales , Femenino , Xenoinjertos , Humanos , Melanoma/metabolismo , Glicoproteínas de Membrana/metabolismo , Ratones , Monocitos/metabolismo , Células Supresoras de Origen Mieloide/metabolismo , Receptores Inmunológicos/metabolismoRESUMEN
Signal transducer and activator of transcription (STAT) proteins have critical roles in the development and function of immune cells. STAT signaling is often dysregulated in patients with inflammatory bowel disease (IBD), suggesting the importance of STAT regulation during the disease process. Moreover, genetic alterations in STAT3 and STAT5 (e.g., deletions, mutations, and single-nucleotide polymorphisms) are associated with an increased risk for IBD. In this study, we elucidated the precise roles of STAT5 signaling in group 3 innate lymphoid cells (ILC3s), a key subset of immune cells involved in the maintenance of gut barrier integrity. We show that mice lacking either STAT5a or STAT5b are more susceptible to Citrobacter rodentium-mediated colitis and that interleukin-2 (IL-2)- and IL-23-induced STAT5 drives IL-22 production in both mouse and human colonic lamina propria ILC3s. Mechanistically, IL-23 induces a STAT3-STAT5 complex that binds IL-22 promoter DNA elements in ILC3s. Our data suggest that STAT5a/b signaling in ILC3s maintains gut epithelial integrity during pathogen-induced intestinal disease.
Asunto(s)
Colitis/inmunología , Interleucina-23/inmunología , Interleucina-2/inmunología , Interleucinas/biosíntesis , Factor de Transcripción STAT5/inmunología , Animales , Interleucinas/inmunología , Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor de Transcripción STAT3/inmunología , Interleucina-22RESUMEN
Colon inflammation or colitis affects more than 1 million people worldwide. Several pre-clinical models, including chemical-induced (i.e., DSS, TNBS) or pathogen-induced (i.e., Citrobacter rodentium) have been used to study mechanisms involved in the development and regulation of colitis. Anti-CD40 induced colitis model has gained acceptance to study the roles of innate immune cells during acute intestinal inflammation. Here we describe a rapid, robust and reproducible protocol to induce and analyze anti-CD40 mediated colitis in mice.
RESUMEN
Interleukin-22 (IL-22)-producing group 3 innate lymphoid cells (ILC3) maintains gut homeostasis but can also promote inflammatory bowel disease (IBD). The regulation of ILC3-dependent colitis remains to be elucidated. Here we show that Foxp3+ regulatory T cells (Treg cells) prevented ILC3-mediated colitis in an IL-10-independent manner. Treg cells inhibited IL-23 and IL-1ß production from intestinal-resident CX3CR1+ macrophages but not CD103+ dendritic cells. Moreover, Treg cells restrained ILC3 production of IL-22 through suppression of CX3CR1+ macrophage production of IL-23 and IL-1ß. This suppression was contact dependent and was mediated by latent activation gene-3 (LAG-3)-an immune checkpoint receptor-expressed on Treg cells. Engagement of LAG-3 on MHC class II drove profound immunosuppression of CX3CR1+ tissue-resident macrophages. Our study reveals that the health of the intestinal mucosa is maintained by an axis driven by Treg cells communication with resident macrophages that withhold inflammatory stimuli required for ILC3 function.
Asunto(s)
Antígenos CD/metabolismo , Receptor 1 de Quimiocinas CX3C/metabolismo , Colitis/inmunología , Colitis/patología , Subunidad p19 de la Interleucina-23/inmunología , Mucosa Intestinal/patología , Macrófagos/inmunología , Linfocitos T Reguladores/inmunología , Animales , Células Cultivadas , Células Dendríticas/inmunología , Factores de Transcripción Forkhead/metabolismo , Antígenos de Histocompatibilidad Clase II/inmunología , Interleucina-10/inmunología , Interleucina-1beta/inmunología , Interleucinas/inmunología , Mucosa Intestinal/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Linfocitos T Reguladores/trasplante , Proteína del Gen 3 de Activación de Linfocitos , Interleucina-22RESUMEN
GITR is a costimulatory receptor currently undergoing phase I clinical trials. Efficacy of anti-GITR therapy in syngeneic mouse models requires regulatory T-cell depletion and CD8+ T-cell costimulation. It is increasingly appreciated that immune cell proliferation and function are dependent on cellular metabolism. Enhancement of diverse metabolic pathways leads to different immune cell fates. Little is known about the metabolic effects of GITR agonism; thus, we investigated whether costimulation via GITR altered CD8+ T-cell metabolism. We found activated, GITR-treated CD8+ T cells upregulated nutrient uptake, lipid stores, glycolysis, and oxygen consumption rate (OCR) in vitro Using MEK, PI3Kδ, and metabolic inhibitors, we show increased metabolism is required, but not sufficient, for GITR antibody (DTA-1)-induced cellular proliferation and IFNγ production. In an in vitro model of PD-L1-induced CD8+ T-cell suppression, GITR agonism alone rescued cellular metabolism and proliferation, but not IFNγ production; however, DTA-1 in combination with anti-PD-1 treatment increased IFNγ production. In the MC38 mouse tumor model, GITR agonism significantly increased OCR and IFNγ and granzyme gene expression in both tumor and draining lymph node (DLN) CD8+ T cells ex vivo, as well as basal glycolysis in DLN and spare glycolytic capacity in tumor CD8+ T cells. DLN in GITR-treated mice showed significant upregulation of proliferative gene expression compared with controls. These data show that GITR agonism increases metabolism to support CD8+ T-cell proliferation and effector function in vivo, and that understanding the mechanism of action of agonistic GITR antibodies is crucial to devising effective combination therapies. Cancer Immunol Res; 6(10); 1199-211. ©2018 AACR.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Neoplasias del Colon/inmunología , Citocinas/inmunología , Proteína Relacionada con TNFR Inducida por Glucocorticoide/agonistas , Proteína Relacionada con TNFR Inducida por Glucocorticoide/inmunología , Animales , Anticuerpos/farmacología , Antígeno B7-H1/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Ratones Endogámicos C57BLRESUMEN
Agonistic monoclonal antibodies (mAb) targeting the T-cell receptor coregulatory molecule GITR exert potent therapeutic activities in preclinical tumor models. Although anti-GITR mAb are thought to act by depleting and destabilizing the intratumoral T regulatory cell (Treg) population, the precise mechanism of action is obscure. Here, we addressed this issue using a Treg fate-mapping approach, which revealed that Treg loss was primarily due to cell depletion, with minimal evidence of Treg conversion to a non-Foxp3-expressing population. Further characterization of persisting Tregs following anti-GITR mAb treatment showed that a highly activated subpopulation of CD44hiICOShi intratumoral Tregs were preferentially targeted for elimination, with the remaining Tregs exhibiting a less suppressive phenotype. With these changes in the Treg population, intratumoral CD8+ T cells acquired a more functional phenotype characterized by downregulation of the exhaustion markers PD-1 and LAG-3. This reversal of CD8+ T-cell exhaustion was dependent on both agonistic GITR signaling and Treg depletion, as neither mechanism by itself could fully rescue the exhaustion phenotype. Tests of anti-human GITR antibody MK-4166 in a humanized mouse model of cancer mimicked many of the effects of anti-mouse GITR mAb in syngeneic tumor models, decreasing both Treg numbers and immune suppressor phenotype while enhancing effector responsiveness. Overall, our results show how anti-GITR mAb shifts Treg populations to enable immune attack on tumors, with clinical implications for molecular markers to modify emerging treatments. Cancer Res; 77(5); 1108-18. ©2016 AACR.
Asunto(s)
Anticuerpos Monoclonales/farmacología , Neoplasias del Colon/terapia , Proteína Relacionada con TNFR Inducida por Glucocorticoide/inmunología , Depleción Linfocítica/métodos , Melanoma/terapia , Linfocitos T Reguladores/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Línea Celular Tumoral , Neoplasias del Colon/inmunología , Proteína Relacionada con TNFR Inducida por Glucocorticoide/agonistas , Humanos , Inmunoterapia/métodos , Melanoma/inmunología , Ratones , Ratones Endogámicos C57BL , Transducción de SeñalRESUMEN
Recent studies have elucidated the molecular mechanism of RORγT transcriptional regulation of Th17 differentiation and function. RORγT was initially identified as a transcription factor required for thymopoiesis by maintaining survival of CD4+CD8+ (DP) thymocytes. While RORγ antagonists are currently being developed to treat autoimmunity, it remains unclear how RORγT inhibition may impact thymocyte development. In this study, we show that in addition to regulating DP thymocytes survival, RORγT also controls genes that regulate thymocyte migration, proliferation, and T cell receptor (TCR)α selection. Strikingly, pharmacological inhibition of RORγ skews TCRα gene rearrangement, limits T cell repertoire diversity, and inhibits development of autoimmune encephalomyelitis. Thus, targeting RORγT not only inhibits Th17 cell development and function but also fundamentally alters thymic-emigrant recognition of self and foreign antigens. The analysis of RORγ inhibitors has allowed us to gain a broader perspective of the diverse function of RORγT and its impact on T cell biology.
Asunto(s)
Encefalomielitis Autoinmune Experimental/inmunología , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Timocitos/inmunología , Animales , Antígenos/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Diferenciación Celular/genética , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/terapia , Regulación de la Expresión Génica/inmunología , Reordenamiento Génico/genética , Humanos , Ratones , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/inmunología , Receptores de Antígenos de Linfocitos T alfa-beta/antagonistas & inhibidores , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Células Th17/efectos de los fármacos , Células Th17/inmunologíaRESUMEN
Chronic obstructive pulmonary disease (COPD) is a devastating disease with no effective therapies. We investigated the role of the C-type lectin receptor, CLEC5A, in macrophage activation and pulmonary pathogenesis in a mouse model of COPD. We demonstrate that CLEC5A is expressed on alveolar macrophages in mice exposed long-term to cigarette smoke (CS), as well as in human smokers. We also show that CLEC5A-mediated activation of macrophages enhanced cytokine elaboration alone, as well as in combination with LPS or GM-CSF in CS-exposed mice. Furthermore, usingClec5a-deficient mice, we demonstrate that CS-induced macrophage responsiveness is mediated by CLEC5A, and CLEC5A is required for the development of inflammation, proinflammatory cytokine expression, and airspace enlargement. These findings suggest a novel mechanism that promotes airway inflammation and pathologies in response to CS exposure and identifies CLEC5A as a novel target for the therapeutic control of COPD pathogenesis.
Asunto(s)
Lectinas Tipo C/inmunología , Activación de Macrófagos/inmunología , Macrófagos Alveolares/inmunología , Enfermedad Pulmonar Obstructiva Crónica/inmunología , Receptores de Superficie Celular/inmunología , Contaminación por Humo de Tabaco/efectos adversos , Animales , Líquido del Lavado Bronquioalveolar/citología , Células Cultivadas , Citocinas/metabolismo , Modelos Animales de Enfermedad , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Inflamación/inmunología , Lectinas Tipo C/genética , Lipopolisacáridos/efectos adversos , Pulmón/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Enfermedad Pulmonar Obstructiva Crónica/patología , Receptores de Superficie Celular/genéticaRESUMEN
Interleukin-23 (IL-23) is a pro-inflammatory cytokine required for the pathogenicity of T helper 17 (Th17) cells but the molecular mechanisms governing this process remain unclear. We identified the transcription factor Blimp-1 (Prdm1) as a key IL-23-induced factor that drove the inflammatory function of Th17 cells. In contrast to thymic deletion of Blimp-1, which causes T cell development defects and spontaneous autoimmunity, peripheral deletion of this transcription factor resulted in reduced Th17 activation and reduced severity of autoimmune encephalomyelitis. Furthermore, genome-wide occupancy and overexpression studies in Th17 cells revealed that Blimp-1 co-localized with transcription factors RORγt, STAT-3, and p300 at the Il23r, Il17a/f, and Csf2 cytokine loci to enhance their expression. Blimp-1 also directly bound to and repressed cytokine loci Il2 and Bcl6. Taken together, our results demonstrate that Blimp-1 is an essential transcription factor downstream of IL-23 that acts in concert with RORγt to activate the Th17 inflammatory program.
Asunto(s)
Regulación de la Expresión Génica/inmunología , Inflamación/inmunología , Activación de Linfocitos/inmunología , Células Th17/inmunología , Factores de Transcripción/inmunología , Animales , Diferenciación Celular/inmunología , Separación Celular , Inmunoprecipitación de Cromatina , Encefalomielitis Autoinmune Experimental/inmunología , Interleucina-23/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Factor 1 de Unión al Dominio 1 de Regulación Positiva , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción GenéticaRESUMEN
Whether interleukin-17A (IL-17A) has pathogenic and/or protective roles in the gut mucosa is controversial and few studies have analyzed specific cell populations for protective functions within the inflamed colonic tissue. Here we have provided evidence for IL-17A-dependent regulation of the tight junction protein occludin during epithelial injury that limits excessive permeability and maintains barrier integrity. Analysis of epithelial cells showed that in the absence of signaling via the IL-17 receptor adaptor protein Act-1, the protective effect of IL-17A was abrogated and inflammation was enhanced. We have demonstrated that after acute intestinal injury, IL-23R(+) γδ T cells in the colonic lamina propria were the primary producers of early, gut-protective IL-17A, and this production of IL-17A was IL-23 independent, leaving protective IL-17 intact in the absence of IL-23. These results suggest that IL-17-producing γδ T cells are important for the maintenance and protection of epithelial barriers in the intestinal mucosa.
Asunto(s)
Colitis/fisiopatología , Interleucina-17/fisiología , Interleucina-23/fisiología , Mucosa Intestinal/fisiopatología , Enfermedad Aguda , Proteínas Adaptadoras Transductoras de Señales/deficiencia , Proteínas Adaptadoras Transductoras de Señales/fisiología , Animales , Línea Celular Tumoral , Polaridad Celular , Colitis/inducido químicamente , Neoplasias del Colon/patología , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Epitelio/fisiopatología , Proteínas de Homeodominio/fisiología , Humanos , Interleucina-17/deficiencia , Interleucina-17/farmacología , Subgrupos Linfocitarios/metabolismo , Ratones , Ratones Noqueados , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/deficiencia , Ocludina/metabolismo , Permeabilidad , Transporte de Proteínas , Receptores de Antígenos de Linfocitos T gamma-delta/análisis , Proteínas Recombinantes/farmacología , Uniones Estrechas/fisiología , Factor de Necrosis Tumoral alfa/farmacologíaRESUMEN
Interleukin-23 (IL-23) is essential for the differentiation of pathogenic effector T helper 17 (Th17) cells, but its role in memory Th17 cell responses is unclear. Using the experimental autoimmune encephalomyelitis (EAE) model, we report that memory Th17 cells rapidly expanded in response to rechallenge and migrated to the CNS in high numbers, resulting in earlier onset and increased severity of clinical disease. Memory Th17 cells were generated from IL-17+ and RORγt+ precursors, and the stability of the Th17 cell phenotype depended on the amount of time allowed for the primary response. IL-23 was required for this enhanced recall response. IL-23 receptor blockade did not directly impact IL-17 production, but did impair the subsequent proliferation and generation of effectors coexpressing the Th1 cell-specific transcription factor T-bet. In addition, many genes required for cell-cycle progression were downregulated in Th17 cells that lacked IL-23 signaling, showing that a major mechanism for IL-23 in primary and memory Th17 cell responses operates via regulation of proliferation-associated pathways.
Asunto(s)
Interleucina-23/metabolismo , Células Th17/metabolismo , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/trasplante , Citocinas/metabolismo , Regulación de la Expresión Génica , Interleucina-17/metabolismo , Ratones , Ratones Endogámicos C57BL , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Transducción de Señal , Proteínas de Dominio T Box/metabolismo , Células Th17/citología , Células Th17/inmunología , Trasplante HomólogoRESUMEN
OBJECTIVES: Interleukin-23 (IL-23) has emerged as a new therapeutic target for the treatment of inflammatory bowel disease (IBD). As biomarkers of disease state and treatment efficacy are becoming increasingly important in drug development, we sought to identify efficacy biomarkers for anti-IL-23 therapy in Crohn's disease (CD). METHODS: Candidate IL-23 biomarkers, downstream of IL-23 signaling, were identified using shotgun proteomic analysis of feces and colon lavages obtained from a short-term mouse IBD model (anti-CD40 Rag2(-/-)) treated preventively with monoclonal antibodies (mAbs) to the IL-23 receptor (IL-23R). The biomarkers were then measured in an IBD T-cell transfer model treated therapeutically with a mAb to IL-23 (p19), confirming their association with IBD. To assess the clinical relevance of these markers, we assessed their concentrations in clinical serum, colon tissue, and feces from CD patients. RESULTS: We identified 57 proteins up or downregulated in diseased animals that returned to control values when the mice were treated with mAbs to IL-23R. Among those, S100A8, S100A9, regenerating protein 3ß (REG), REG3γ, lipocalin 2 (LCN2), deleted in malignant tumor 1 (DMBT1), and macrophage migration inhibitory factor (MIF) mRNA levels correlated with disease score and dose titration of mAbs to IL-23R or IL-23(p19). All biomarkers, except DMBT1, were also downregulated after therapeutic administration of mAbs to IL-23(p19) in a T-cell transfer IBD mouse model. In sera from CD patients, we confirmed a significant upregulation of S100A8/A9 (43%), MIF (138%), pancreatitis-associated protein (PAP, human homolog of REG3ß/γ; 49%), LCN2 (520%), and CCL20 (1280%), compared with control samples, as well as a significant upregulation of S100A8/A9 (887%), PAP (401%), and LCN2 (783%) in human feces from CD patients compared with normal controls. CONCLUSIONS: These studies identify multiple protein biomarkers downstream of IL-23 that could be valuable tools to assess the efficacy of this new therapeutic agent.Clinical and Translational Gastroenterology (2012) 3, e10; doi:10.1038/ctg.2012.2; published online 16 February 2012.
RESUMEN
The spondyloarthropathies are a group of rheumatic diseases that are associated with inflammation at anatomically distal sites, particularly the tendon-bone attachments (entheses) and the aortic root. Serum concentrations of interleukin-23 (IL-23) are elevated and polymorphisms in the IL-23 receptor are associated with ankyosing spondylitis, however, it remains unclear whether IL-23 acts locally at the enthesis or distally on circulating cell populations. We show here that IL-23 is essential in enthesitis and acts on previously unidentified IL-23 receptor (IL-23R)(+), RAR-related orphan receptor γt (ROR-γt)(+)CD3(+)CD4(-)CD8(-), stem cell antigen 1 (Sca1)(+) entheseal resident T cells. These cells allow entheses to respond to IL-23 in vitro-in the absence of further cellular recruitment--and to elaborate inflammatory mediators including IL-6, IL-17, IL-22 and chemokine (C-X-C motif) ligand 1 (CXCL1). Notably, the in vivo expression of IL-23 is sufficient to phenocopy the human disease, with the specific and characteristic development of enthesitis and entheseal new bone formation in the initial complete absence of synovitis. As in the human condition, inflammation also develops in vivo at the aortic root and valve, which are structurally similar to entheses. The presence of these entheseal resident cells and their production of IL-22, which activates signal transducer and activator of transcription 3 (STAT3)-dependent osteoblast-mediated bone remodeling, explains why dysregulation of IL-23 results in inflammation at this precise anatomical site.
Asunto(s)
Interleucina-23/inmunología , Espondiloartropatías/inmunología , Linfocitos T/inmunología , Tendones/inmunología , Animales , Antígenos CD/metabolismo , Aorta/patología , Artritis Experimental/complicaciones , Artritis Experimental/inmunología , Artritis Experimental/patología , Remodelación Ósea , Complejo CD3/metabolismo , Antígenos CD4/metabolismo , Antígenos CD8/metabolismo , Modelos Animales de Enfermedad , Extremidades/patología , Citometría de Flujo , Humanos , Inmunización Pasiva , Inflamación/complicaciones , Inflamación/inmunología , Inflamación/patología , Interleucina-17 , Interleucinas , Ratones , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Osteogénesis/inmunología , Periostio/crecimiento & desarrollo , Receptores de Interleucina/metabolismo , Espondiloartropatías/complicaciones , Espondiloartropatías/patología , Tendones/patología , Células Th17 , Interleucina-22RESUMEN
Paired immunoglobulin-like receptors beta, PILRß, and alpha, PILRα, are related to the Siglec family of receptors and are expressed primarily on cells of the myeloid lineage. PILRß is a DAP12 binding partner expressed on both human and mouse myeloid cells. The potential ligand, CD99, is found on many cell types, such as epithelial cells where it plays a role in migration of immune cells to sites of inflammation. Pilrb deficient mice were challenged with the parasite Toxoplasma gondii in two different models of infection induced inflammation; one involving the establishment of chronic encephalitis and a second mimicking inflammatory bowel disease in order to understand the potential role of this receptor in persistent inflammatory responses. It was found that in the absence of activating signals from PILRß, antigen-presenting cells (APCs) produced increased amounts of IL-27, p28 and promoted IL-10 production in effector T cells. The sustained production of IL-27 led ultimately to enhanced survival after challenge due to dampened immune pathology in the gut. Similar protection was also observed in the CNS during chronic T. gondii infection after i.p. challenge again providing evidence that PILRß is important for regulating aberrant inflammatory responses.
Asunto(s)
Inflamación/inmunología , Interleucinas/inmunología , Receptores Inmunológicos/inmunología , Linfocitos T/inmunología , Animales , Células Cultivadas , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Encefalitis/genética , Encefalitis/inmunología , Encefalitis/metabolismo , Femenino , Expresión Génica , Inflamación/genética , Inflamación/metabolismo , Interferón gamma/genética , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Ratones Noqueados , Microglía/inmunología , Microglía/metabolismo , Receptores Inmunológicos/deficiencia , Receptores Inmunológicos/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T/metabolismo , Toxoplasma/inmunología , Toxoplasmosis Animal/genética , Toxoplasmosis Animal/inmunología , Toxoplasmosis Animal/metabolismoRESUMEN
C17 was first described about ten years ago as a gene expressed in CD34+ cells. A more recent study has suggested a role for C17 in chondrogenesis and development of cartilage. However, based on sequence analysis, we believe that C17 has homology to IL-2 and hence we present the hypothesis that C17 is a cytokine possessing immune-regulatory properties. We provide evidence that C17 is a secreted protein preferentially expressed in chondrocytes, hence in cartilage-rich tissues. Systemic expression of C17 in vivo reduces disease in a collagen antibody-induced arthritis model in mice (CAIA). Joint protection is evident by delayed disease onset, minimal edema, bone protection and absence of diverse histological features of disease. Expression of genes typically associated with acute joint inflammation and erosion of cartilage or bone is blunted in the presence of C17. Consistent with the observed reduction in bone erosion, we demonstrate reduced levels of RANKL in the paws and sera of mice over-expressing C17. Administration of C17 at the peak of disease, however, had no effect on disease progression, indicating that C17's immune-regulatory activity must be most prominent prior to or at the onset of severe joint inflammation. Based on this data we propose C17 as a cytokine that s contributes to immune homeostasis systemically or in a tissue-specific manner in the joint.
Asunto(s)
Artritis/metabolismo , Proteínas Sanguíneas/metabolismo , Citocinas/metabolismo , Articulaciones/metabolismo , Articulaciones/patología , Secuencia de Aminoácidos , Animales , Artritis/inmunología , Artritis/patología , Artritis/terapia , Biomarcadores/metabolismo , Proteínas Sanguíneas/química , Proteínas Sanguíneas/genética , Enfermedades Óseas/complicaciones , Enfermedades Óseas/metabolismo , Cartílago/metabolismo , Condrocitos/metabolismo , Citocinas/química , Citocinas/genética , Regulación de la Expresión Génica , Células HEK293 , Homeostasis/inmunología , Humanos , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/patología , Inflamación/terapia , Articulaciones/inmunología , Masculino , Ratones , Datos de Secuencia Molecular , Ligando RANK/sangreRESUMEN
Inflammatory mediators have the potential to impact a surprising range of diseases, including obesity and its associated metabolic syndrome. In this paper, we show that the proinflammatory cytokine IL-17 inhibits adipogenesis, moderates adipose tissue (AT) accumulation, and regulates glucose metabolism in mice. IL-17 deficiency enhances diet-induced obesity in mice and accelerates AT accumulation even in mice fed a low-fat diet. In addition to potential systemic effects, IL-17 is expressed locally in AT by leukocytes, predominantly by γδ T cells. IL-17 suppresses adipocyte differentiation from mouse-derived 3T3-L1 preadipocytes in vitro, and inhibits expression of genes encoding proadipogenic transcription factors, adipokines, and molecules involved in lipid and glucose metabolism. IL-17 also acts on differentiated adipocytes, impairing glucose uptake, and young IL-17-deficient mice show enhanced glucose tolerance and insulin sensitivity. Our findings implicate IL-17 as a negative regulator of adipogenesis and glucose metabolism in mice, and show that it delays the development of obesity.
Asunto(s)
Adipogénesis/inmunología , Tejido Adiposo/citología , Tejido Adiposo/inmunología , Glucosa/metabolismo , Homeostasis/inmunología , Interleucina-17/fisiología , Obesidad/inmunología , Células 3T3-L1 , Adipogénesis/genética , Tejido Adiposo/metabolismo , Tejido Adiposo/patología , Animales , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Regulación hacia Abajo/genética , Regulación hacia Abajo/inmunología , Glucosa/antagonistas & inhibidores , Inhibidores de Crecimiento/genética , Inhibidores de Crecimiento/inmunología , Resistencia a la Insulina/inmunología , Interleucina-17/biosíntesis , Interleucina-17/deficiencia , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Obesidad/metabolismo , Obesidad/patología , Receptores de Antígenos de Linfocitos T gamma-delta/biosíntesis , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Subgrupos de Linfocitos T/patologíaRESUMEN
DNAX adaptor protein 12 (DAP12) is a trans-membrane adaptor molecule that transduces activating signals in NK and myeloid cells. Absence of functional Dap12 results in osteoclast defects and bone abnormalities. Because DAP12 has no extracelluar binding domains, it must pair with cell surface receptors for signal transduction. There are at least 15 known DAP12-associating cell surface receptors with distinct temporal and cell type-specific expression patterns. Our aim was to determine which receptors may be important in DAP12-associated bone pathologies. Here, we identify myeloid DAP12-associating lectin (MDL)-1 receptor (also known as CLEC5A) as a key regulator of synovial injury and bone erosion during autoimmune joint inflammation. Activation of MDL-1 leads to enhanced recruitment of inflammatory macrophages and neutrophils to the joint and promotes bone erosion. Functional blockade of MDL-1 receptor via Mdl1 deletion or treatment with MDL-1-Ig fusion protein reduces the clinical signs of autoimmune joint inflammation. These findings suggest that MDL-1 receptor may be a therapeutic target for treatment of immune-mediated skeletal disorders.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/fisiología , Inflamación/inmunología , Lectinas Tipo C/fisiología , Proteínas de la Membrana/fisiología , Receptores de Superficie Celular/fisiología , Proteínas Adaptadoras Transductoras de Señales/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Artritis Reumatoide/inmunología , Artritis Reumatoide/fisiopatología , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/terapia , Células de la Médula Ósea/inmunología , Células de la Médula Ósea/fisiología , Regulación de la Expresión Génica , Humanos , Inflamación/fisiopatología , Inflamación/terapia , Artropatías/inmunología , Células Asesinas Naturales/inmunología , Lectinas Tipo C/genética , Lectinas Tipo C/inmunología , Proteínas de la Membrana/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Osteoblastos/fisiología , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/inmunologíaRESUMEN
IL-27 is secreted by APCs in response to inflammatory stimuli and exerts a proinflammatory Th1-enhancing activity but also has significant anti-inflammatory functions. We examined the molecular mechanism by which IL-27 regulates TGFbeta plus IL-6- or IL-23-dependent Th17 development in the mouse and human systems. IL-27 inhibited the production of IL-17A and IL-17F in naive T cells by suppressing, in a STAT1-dependent manner, the expression of the Th17-specific transcription factor RORgamma t. The in vivo significance of the role of IL-27 was addressed in delayed-type hypersensitivity response and experimental autoimmune encephalomyelitis (EAE). By generating mice deficient for the p28 subunit of IL-27, we showed that IL-27 regulated the severity of delayed-type hypersensitivity response and EAE through its effects on Th17 cells. Furthermore, up-regulation of IL-10 in the CNS, which usually occurs late after EAE onset and plays a role in the resolution of the disease, was notably absent in IL-27p28(-/-) mice. These results show that IL-27 acts as a negative regulator of the developing IL-17A response in vivo, suggesting a potential therapeutic role for IL-27 in autoimmune diseases.
Asunto(s)
Linaje de la Célula/inmunología , Inhibidores de Crecimiento/fisiología , Interleucina-17/antagonistas & inhibidores , Interleucinas/fisiología , Receptores de Ácido Retinoico/antagonistas & inhibidores , Receptores de Hormona Tiroidea/antagonistas & inhibidores , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Linaje de la Célula/genética , Células Cultivadas , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/patología , Regulación de la Expresión Génica/inmunología , Predisposición Genética a la Enfermedad , Inhibidores de Crecimiento/deficiencia , Inhibidores de Crecimiento/genética , Humanos , Interleucina-17/biosíntesis , Interleucinas/deficiencia , Interleucinas/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares , Subunidades de Proteína/deficiencia , Subunidades de Proteína/genética , Subunidades de Proteína/fisiología , Receptores de Ácido Retinoico/biosíntesis , Receptores de Ácido Retinoico/genética , Receptores de Hormona Tiroidea/biosíntesis , Receptores de Hormona Tiroidea/genética , Linfocitos T Colaboradores-Inductores/metabolismo , Linfocitos T Colaboradores-Inductores/patologíaRESUMEN
Interleukin 23 (IL-23) is required for autoimmune inflammation mediated by IL-17-producing helper T cells (T(H)-17 cells) and has been linked to many human immune disorders. Here we restricted deficiency in the IL-23 receptor to defined cell populations in vivo to investigate the requirement for IL-23 signaling in the development and function of T(H)-17 cells in autoimmunity, inflammation and infection. In the absence of IL-23, T(H)-17 development was stalled at the early activation stage. T(H)-17 cells failed to downregulate IL-2 and also failed to maintain IL-17 production or upregulate expression of the IL-7 receptor alpha-chain. These defects were associated with less proliferation; consequently, fewer effector T(H)-17 cells were produced in the lymph nodes and hence available to emigrate to the bloodstream and tissues.
Asunto(s)
Diferenciación Celular , Interleucina-17/biosíntesis , Receptores de Interleucina/metabolismo , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Proliferación Celular , Encefalomielitis Autoinmune Experimental/inducido químicamente , Femenino , Interleucina-2/metabolismo , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Interleucina/deficiencia , Factor de Transcripción STAT3/metabolismo , Linfocitos T Colaboradores-Inductores/metabolismo , Toxoplasmosis Animal/inmunologíaRESUMEN
In infection with the trematode helminth Schistosoma mansoni, the severity of CD4 T cell-mediated hepatic granulomatous and fibrosing inflammation against parasite eggs varies considerably in humans and among mouse strains. In mice, either the natural high pathology, or high pathology induced by concomitant immunization with schistosome egg Ags (SEA) in CFA (SEA/CFA), results from a failure to contain a net proinflammatory cytokine environment. We previously demonstrated that the induction of severe immunopathology was dependent on the IL-12/IL-23 common p40 subunit, and correlated with an increase in IL-17, thus implying IL-23 in the pathogenesis. We now show that mice lacking the IL-23-specific subunit p19 are impaired in developing severe immunopathology following immunization with SEA/CFA, which is associated with a marked drop of IL-17 in the granulomas, but not in the draining mesenteric lymph nodes, and with a markedly suppressed SEA-specific IFN-gamma response regulated by a striking increase in IL-10. The granulomas are characterized by a significant reduction in Gr-1(+) cell recruitment and by alternative macrophage activation. Taken together, these results demonstrate that IL-23 per se is not necessary for the generation of IL-17-producing T cells, but is essential for the development of severe schistosome egg-induced immunopathology, and its absence cannot be overcome with other possible compensatory mechanisms.