RESUMEN
Glucocorticoids are steroid hormones well-known for their potent anti-inflammatory effects. However, their immunomodulatory properties are multifaceted. Increasing evidence suggests that glucocorticoid signaling promotes effective immunity and that disruption of glucocorticoid signaling impairs immune function. In this study, we conditionally deleted the glucocorticoid receptor (GR) in the myeloid lineage using the LysM-Cre driver (myGRKO). We examined the impact on macrophage activation and gastric immune responses to Helicobacter pylori, the best-known risk factor of gastric cancer. Our results indicate that, compared to WT, GRKO macrophages exhibited higher expression of proinflammatory genes in steroid-free conditions. However, when challenged in vivo, GRKO macrophages exhibited aberrant chromatin landscapes and impaired proinflammatory gene expression profiles. Moreover, gastric colonization with Helicobacter pylori revealed impaired gastric immune responses and reduced T cell recruitment in myGRKO mice. As a result, myGRKO mice were protected from atrophic gastritis and pyloric metaplasia development. These results demonstrate a dual role for glucocorticoid signaling in preparing macrophages to respond to bacterial infection but limiting their pathogenic activation. In addition, our results support that macrophages are critical for gastric Helicobacter pylori immunity.
RESUMEN
The role of interferons, either pathogenic or protective, during autoimmune diabetes remains controversial. Herein, we examine the progression of diabetes in NOD mice lacking the type I (IFNAR) or type II (IFNGR) interferon receptor and, for the first time, in mice deficient in both receptors (double knockout [DKO]). All mice were bred, maintained, and monitored in a single specific pathogen-free facility with high female and low male diabetes incidence. Our expectation was that removal of interferon signaling would reduce autoimmune destruction. However, examination of diabetes incidence in the IFNAR- and IFNGR-deficient NOD mice showed a reduction in females and an increase in males. In DKO mice, diabetes occurred only in female mice, at decreased incidence and with delayed kinetics. These results show that interferons act as both positive and negative modulators of type 1 diabetes disease risk dependent on sex.
Asunto(s)
Envejecimiento , Enfermedades Autoinmunes/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Islotes Pancreáticos/metabolismo , Receptor de Interferón alfa y beta/metabolismo , Animales , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/patología , Enfermedades Autoinmunes/fisiopatología , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/patología , Diabetes Mellitus Tipo 1/fisiopatología , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Islotes Pancreáticos/inmunología , Islotes Pancreáticos/patología , Islotes Pancreáticos/fisiopatología , Leucocitos/inmunología , Leucocitos/metabolismo , Leucocitos/patología , Masculino , Ratones Endogámicos NOD , Ratones Noqueados , Receptor de Interferón alfa y beta/genética , Caracteres Sexuales , Organismos Libres de Patógenos EspecíficosRESUMEN
AIMS/HYPOTHESIS: We studied here the interactions between the resident macrophages of pancreatic islets with beta cells and the blood vasculature. We also examined the immunological consequences of such interactions. METHODS: Islets were isolated from C57BL/6 mice expressing CX3C motif chemokine receptor 1-green fluorescent protein (CX3CR-GFP) and examined live by two-photon microscopy. Islets were also examined by electron microscopy to study the relationship of the intra-islet macrophages with the beta cells. In NOD.Rag1-/- mice and young (non-diabetic) male mice, the acquisition of beta cell granules was tested functionally by probing with CD4+ T cells directed against insulin epitopes. RESULTS: Two-photon microscopy showed that the islet resident macrophages were in close contact with blood vessels and had extensive filopodial activity. Some filopodia had direct access to the vessel lumen and captured microparticles. Addition of glucose at high concentration reduced the degree of filopodia sampling of islets. This finding applied to in vivo injection of glucose or to in vitro cultures. Ultrastructural examination showed the close contacts of macrophages with beta cells. Such macrophages contained intact dense core granules. Functional studies in NOD mice indicated that the macrophages presented insulin peptides to insulin-reactive T cells. Presentation was increased after glucose challenge either ex vivo or after an in vivo pulse. In agreement with the morphological findings, presentation was not affected by insulin receptor blockade. CONCLUSIONS/INTERPRETATION: Islet resident macrophages are highly active, sampling large areas of the islets and blood contents and capturing beta cell granules. After such interactions, macrophages present immunogenic insulin to specific autoreactive T cells.
Asunto(s)
Células Secretoras de Insulina/citología , Islotes Pancreáticos/citología , Macrófagos/citología , Animales , Linfocitos T CD4-Positivos/inmunología , Diabetes Mellitus Experimental/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Proteínas de Homeodominio/metabolismo , Insulina/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Noqueados , MicroscopíaRESUMEN
Dendritic cells (DCs) are thought to form a dendritic network across barrier surfaces and throughout organs, including the kidney, to perform an important sentinel function. However, previous studies of DC function used markers, such as CD11c or CX3CR1, that are not unique to DCs. Here, we evaluated the role of DCs in renal inflammation using a CD11c reporter mouse line and two mouse lines with DC-specific reporters, Zbtb46-GFP and Snx22-GFP. Multiphoton microscopy of kidney sections confirmed that most of the dendritically shaped CD11c+ cells forming a network throughout the renal interstitium expressed macrophage-specific markers. In contrast, DCs marked by Zbtb46-GFP or Snx22-GFP were less abundant, concentrated around blood vessels, and round in shape. We confirmed this pattern of localization using imaging mass cytometry. Motility measurements showed that resident macrophages were sessile, whereas DCs were motile before and after inflammation. Although uninflamed glomeruli rarely contained DCs, injury with nephrotoxic antibodies resulted in accumulation of ZBTB46 + cells in the periglomerular region. ZBTB46 identifies all classic DCs, which can be categorized into two functional subsets that express either CD103 or CD11b. Depletion of ZBTB46 + cells attenuated the antibody-induced kidney injury, whereas deficiency of the CD103+ subset accelerated injury through a mechanism that involved increased neutrophil infiltration. RNA sequencing 7 days after nephrotoxic antibody injection showed that CD11b+ DCs expressed the neutrophil-attracting cytokine CXCL2, whereas CD103+ DCs expressed high levels of several anti-inflammatory genes. These results provide new insights into the distinct functions of the two major DC subsets in glomerular inflammation.
Asunto(s)
Células Dendríticas/fisiología , Glomerulonefritis/inmunología , Glomerulonefritis/patología , Animales , Antígenos CD/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Antígenos CD11/genética , Antígeno CD11b/genética , Movimiento Celular , Quimiocina CXCL2/genética , Células Dendríticas/metabolismo , Células Dendríticas/patología , Expresión Génica , Genes Reporteros , Proteínas Fluorescentes Verdes/metabolismo , Cadenas alfa de Integrinas/metabolismo , Macrófagos , Masculino , Ratones , Ratones Noqueados , Neutrófilos/patología , Neutrófilos/fisiología , Proteínas Represoras/genética , Análisis de Secuencia de ARN , Nexinas de Clasificación/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , TranscriptomaRESUMEN
Treatment of C57BL/6 or NOD mice with a monoclonal antibody to the CSF-1 receptor resulted in depletion of the resident macrophages of pancreatic islets of Langerhans that lasted for several weeks. Depletion of macrophages in C57BL/6 mice did not affect multiple parameters of islet function, including glucose response, insulin content, and transcriptional profile. In NOD mice depleted of islet-resident macrophages starting at 3 wk of age, several changes occurred: (i) the early entrance of CD4 T cells and dendritic cells into pancreatic islets was reduced, (ii) presentation of insulin epitopes by dispersed islet cells to T cells was impaired, and (iii) the development of autoimmune diabetes was significantly reduced. Treatment of NOD mice starting at 10 wk of age, when the autoimmune process has progressed, also significantly reduced the incidence of diabetes. Despite the absence of diabetes, NOD mice treated with anti-CSF-1 receptor starting at 3 or 10 wk of age still contained variably elevated leukocytic infiltrates in their islets when examined at 20-40 wk of age. Diabetes occurred in the anti-CSF-1 receptor protected mice after treatment with a blocking antibody directed against PD-1. We conclude that treatment of NOD mice with an antibody against CSF-1 receptor reduced diabetes incidence and led to the development of a regulatory pathway that controlled autoimmune progression.
Asunto(s)
Autoinmunidad , Diabetes Mellitus Tipo 1/inmunología , Islotes Pancreáticos/inmunología , Macrófagos/inmunología , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Animales , Anticuerpos Monoclonales/farmacología , Presentación de Antígeno/inmunología , Linfocitos T CD4-Positivos/inmunología , Células Dendríticas/inmunología , Diabetes Mellitus Tipo 1/sangre , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Epítopos/inmunología , Femenino , Insulina/inmunología , Islotes Pancreáticos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/inmunología , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/antagonistas & inhibidores , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismoRESUMEN
We examined the transcriptional profiles of macrophages that reside in the islets of Langerhans of 3-wk-old non-obese diabetic (NOD), NOD.Rag1-/-, and B6.g7 mice. Islet macrophages expressed an activation signature with high expression of Tnf, Il1b, and MHC-II at both the transcript and protein levels. These features are common with barrier macrophages of the lung and gastrointestinal tract. Moreover, injection of lipopolysaccharide induced rapid inflammatory gene expression, indicating that blood stimulants are accessible to the macrophages and that these macrophages can sense them. In NOD mice, the autoimmune process imparted an increased inflammatory signature, including elevated expression of chemokines and chemokine receptors and an oxidative response. The elevated inflammatory signature indicates that the autoimmune program was active at the time of weaning. Thus, the macrophages of the islets of Langerhans are poised to mount an immune response even at steady state, while the presence of the adaptive immune system elevates their activation state.
Asunto(s)
Inflamación/fisiopatología , Islotes Pancreáticos/fisiología , Macrófagos/fisiología , Animales , Quimiocinas/metabolismo , Citocinas/metabolismo , Femenino , Citometría de Flujo , Perfilación de la Expresión Génica , Inflamación/metabolismo , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Lipopolisacáridos/sangre , Macrófagos/metabolismo , Ratones Endogámicos NOD , Microscopía Fluorescente , Oxidación-ReducciónRESUMEN
Macrophages produce genotoxic agents, such as reactive oxygen and nitrogen species, that kill invading pathogens. Here we show that these agents activate the DNA damage response (DDR) kinases ATM and DNA-PKcs through the generation of double stranded breaks (DSBs) in murine macrophage genomic DNA. In contrast to other cell types, initiation of this DDR depends on signaling from the type I interferon receptor. Once activated, ATM and DNA-PKcs regulate a genetic program with diverse immune functions and promote inflammasome activation and the production of IL-1ß and IL-18. Indeed, following infection with Listeria monocytogenes, DNA-PKcs-deficient murine macrophages produce reduced levels of IL-18 and are unable to optimally stimulate IFN-γ production by NK cells. Thus, genomic DNA DSBs act as signaling intermediates in murine macrophages, regulating innate immune responses through the initiation of a type I IFN-dependent DDR.
Asunto(s)
Regulación de la Expresión Génica , Inmunidad Innata , Inflamasomas/metabolismo , Interferón Tipo I/metabolismo , Listeria monocytogenes/inmunología , Macrófagos/inmunología , Animales , Roturas del ADN de Doble Cadena , Daño del ADN , Ratones , Proteínas Quinasas/metabolismoRESUMEN
Type I interferons (IFNs) induce a detrimental response during Listeria monocytogenes (L. monocytogenes) infection. We were interested in identifying mechanisms linking IFN signaling to negative host responses against L. monocytogenes infection. Herein, we found that infection of myeloid cells with L. monocytogenes led to a coordinated induction of type I IFNs and activation of the integrated stress response (ISR). Infected cells did not induce Xbp1 splicing or BiP upregulation, indicating that the unfolded protein response was not triggered. CHOP (Ddit3) gene expression was upregulated during the ISR activation induced by L. monocytogenes. Myeloid cells deficient in either type I IFN signaling or PKR activation had less upregulation of CHOP following infection. CHOP-deficient mice showed lower expression of innate immune cytokines and were more resistant than wild-type counterparts following L. monocytogenes infection. These findings indicate that L. monocytogenes infection induces type I IFNs, which activate the ISR through PKR, which contributes to a detrimental outcome in the infected host.
Asunto(s)
Interacciones Huésped-Patógeno , Interferón Tipo I/inmunología , Interferón Tipo I/metabolismo , Listeria monocytogenes/inmunología , Listeriosis/inmunología , Células Mieloides/inmunología , Animales , Toxinas Bacterianas/genética , Toxinas Bacterianas/inmunología , Citocinas/biosíntesis , Citocinas/inmunología , Chaperón BiP del Retículo Endoplásmico , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/inmunología , Proteínas de Choque Térmico/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/inmunología , Interferón Tipo I/biosíntesis , Listeriosis/microbiología , Listeriosis/fisiopatología , Ratones , Células Mieloides/microbiología , Factor de Transcripción CHOP/deficiencia , Factor de Transcripción CHOP/genética , Factor de Transcripción CHOP/metabolismo , Proteína 1 de Unión a la X-Box/genética , Proteína 1 de Unión a la X-Box/metabolismo , eIF-2 Quinasa/metabolismoRESUMEN
Islets of Langerhans of all species harbor a small number of resident macrophages. These macrophages are found since birth, do not exchange with blood monocytes, and are maintained by a low level of replication. Under steady state conditions, the islet macrophages are in an activated state. Islet macrophages have an important homeostatic role in islet physiology. At the start of the autoimmune process in the NOD mouse, a small number of CD103+ dendritic cells (DC) are found at about the same time that CD4+ T cells also appear in islets. In the absence of the CD103+ DC in the Batf3 deficient mice, autoimmunity never develops. We discuss the interactions among the two phagocytes and beta cells that result in autoimmune diabetes in NOD mice.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Células Dendríticas/inmunología , Diabetes Mellitus Tipo 1/inmunología , Islotes Pancreáticos/inmunología , Macrófagos/inmunología , Animales , Presentación de Antígeno , Antígenos CD/metabolismo , Autoinmunidad/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Comunicación Celular , Humanos , Cadenas alfa de Integrinas/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones Noqueados , Proteínas Represoras/genéticaRESUMEN
We have been examining antigen presentation and the antigen presenting cells (APCs) in the islets of Langerhans of the non-obese diabetic (NOD) mouse. The purpose is to identify the earliest events that initiate autoimmunity in this confined tissue. Islets normally have a population of macrophages that is distinct from those that inhabit the exocrine pancreas. Also found in NOD islets is a minor population of dendritic cells (DCs) that bear the CD103 integrin. We find close interactions between beta cells and the two APCs that result in the initiation of the autoimmunity. Even under non-inflammatory conditions, beta cells transfer insulin-containing vesicles to the APCs of the islet. This reaction requires live cells and intimate contact. The autoimmune process starts in islets with the entrance of CD4(+) T cells and an increase in the CD103(+) DCs. Mice deficient in the Batf3 transcription factor never develop diabetes due to the absence of the CD103/CD8α lineage of DCs. We hypothesize that the 12-20 peptide of the beta chain of insulin is responsible for activation of the initial CD4(+) T-cell response during diabetogenesis.
Asunto(s)
Células Presentadoras de Antígenos/inmunología , Autoantígenos/inmunología , Diabetes Mellitus Tipo 1/inmunología , Insulina/inmunología , Islotes Pancreáticos/inmunología , Animales , Presentación de Antígeno , Autoinmunidad , Modelos Animales de Enfermedad , Humanos , Ratones , Ratones Endogámicos NODRESUMEN
This is a brief summary of our studies of NOD autoimmune diabetes examining the events during the initial stage of the process. Our focus has been on antigen presentation events and the antigen presenting cells (APC) inside islets. Islets of non-diabetic mice contain resident macrophages that are developmentally distinct from those in the inter-acinar stroma. The autoimmune process starts with the entrance of CD4+ T cells together with a burst of a subset of dendritic cells (DC) bearing CD103. The CD103+ DC develop under the influence of the Batf3 transcription factor. Batf3 deficient mice do not develop diabetes and their islets are uninfiltrated throughout life. Thus, the CD103+ DC are necessary for the progression of autoimmune diabetes. The major CD4+ T cell response in NOD are the T cells directed to insulin. In particular, the non-conventional 12-20 segment of the insulin B chain is presented by the class II MHC molecule I-A(g7) and elicits pathogenic CD4+ T cells. We discuss that the diabetic process requires the CD103+ DC, the CD4+ T cells to insulin peptides, and NOD specific I-Ag(7) MHC-II allele. Finally, our initial studies indicate that beta cells transfer insulin containing vesicles to the local APC in a contact-dependent reaction. Live images of beta cells interactions with the APC and electron micrographs of islet APCs also show the transfer of granules.
Asunto(s)
Presentación de Antígeno/inmunología , Antígenos/inmunología , Autoinmunidad , Diabetes Mellitus Tipo 1/etiología , Diabetes Mellitus Tipo 1/metabolismo , Animales , Células Presentadoras de Antígenos/inmunología , Células Presentadoras de Antígenos/metabolismo , Biomarcadores , Modelos Animales de Enfermedad , Insulina/inmunología , Insulina/metabolismo , Islotes Pancreáticos/inmunología , Islotes Pancreáticos/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos NOD , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismoRESUMEN
The features that define autoreactive T helper (Th) cell pathogenicity remain obscure. We have previously shown that Th cells require the transcription factor Bhlhe40 to mediate experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis. Here, using Bhlhe40 reporter mice and analyzing both polyclonal and TCR transgenic Th cells, we found that Bhlhe40 expression was heterogeneous after EAE induction, with Bhlhe40-expressing cells displaying marked production of IFN-γ, IL-17A, and granulocyte-macrophage colony-stimulating factor. In adoptive transfer EAE models, Bhlhe40-deficient Th1 and Th17 cells were both nonencephalitogenic. Pertussis toxin (PTX), a classical co-adjuvant for actively induced EAE, promoted IL-1ß production by myeloid cells in the draining lymph node and served as a strong stimulus for Bhlhe40 expression in Th cells. Furthermore, PTX co-adjuvanticity was Bhlhe40 dependent. IL-1ß induced Bhlhe40 expression in polarized Th17 cells, and Bhlhe40-expressing cells exhibited an encephalitogenic transcriptional signature. In vivo, IL-1R signaling was required for full Bhlhe40 expression by Th cells after immunization. Overall, we demonstrate that Bhlhe40 expression identifies encephalitogenic Th cells and defines a PTX-IL-1-Bhlhe40 pathway active in EAE.
Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Encefalomielitis Autoinmune Experimental/inmunología , Proteínas de Homeodominio/metabolismo , Interleucina-1beta/metabolismo , Linfocitos T Colaboradores-Inductores/inmunología , Adyuvantes Inmunológicos , Traslado Adoptivo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Citocinas/biosíntesis , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/patología , Factores de Transcripción Forkhead/metabolismo , Expresión Génica , Proteínas de Homeodominio/genética , Interleucina-10/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Toxina del Pertussis/inmunología , Receptores Tipo I de Interleucina-1/deficiencia , Receptores Tipo I de Interleucina-1/genética , Receptores Tipo I de Interleucina-1/metabolismo , Transducción de Señal , Linfocitos T Colaboradores-Inductores/patologíaRESUMEN
Beta cells from nondiabetic mice transfer secretory vesicles to phagocytic cells. The passage was shown in culture studies where the transfer was probed with CD4 T cells reactive to insulin peptides. Two sets of vesicles were transferred, one containing insulin and another containing catabolites of insulin. The passage required live beta cells in a close cell contact interaction with the phagocytes. It was increased by high glucose concentration and required mobilization of intracellular Ca2+. Live images of beta cell-phagocyte interactions documented the intimacy of the membrane contact and the passage of the granules. The passage was found in beta cells isolated from islets of young nonobese diabetic (NOD) mice and nondiabetic mice as well as from nondiabetic humans. Ultrastructural analysis showed intraislet phagocytes containing vesicles having the distinct morphology of dense-core granules. These findings document a process whereby the contents of secretory granules become available to the immune system.
Asunto(s)
Vesículas Extracelulares/inmunología , Células Secretoras de Insulina/inmunología , Insulina/inmunología , Fagocitos/inmunología , Linfocitos T/inmunología , Adulto , Animales , Presentación de Antígeno/inmunología , Calcio/metabolismo , Comunicación Celular/efectos de los fármacos , Comunicación Celular/inmunología , Células Cultivadas , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Ácido Egtácico/análogos & derivados , Ácido Egtácico/farmacología , Chaperón BiP del Retículo Endoplásmico , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/ultraestructura , Femenino , Expresión Génica/efectos de los fármacos , Glucosa/farmacología , Proteínas de Choque Térmico/genética , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/ultraestructura , Masculino , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Noqueados , Microscopía de Fluorescencia por Excitación Multifotónica , Fagocitos/metabolismo , Fagocitos/ultraestructura , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T/metabolismo , Factor de Transcripción CHOP/genéticaRESUMEN
We examine the features, origin, turnover, and gene expression of pancreatic macrophages under steady state. The data distinguish macrophages within distinct intrapancreatic microenvironments and suggest how macrophage phenotype is imprinted by the local milieu. Macrophages in islets of Langerhans and in the interacinar stroma are distinct in origin and phenotypic properties. In islets, macrophages are the only myeloid cells: they derive from definitive hematopoiesis, exchange to a minimum with blood cells, have a low level of self-replication, and depend on CSF-1. They express Il1b and Tnfa transcripts, indicating classical activation, M1, under steady state. The interacinar stroma contains two macrophage subsets. One is derived from primitive hematopoiesis, with no interchange by blood cells and alternative, M2, activation profile, whereas the second is derived from definitive hematopoiesis and exchanges with circulating myeloid cells but also shows an alternative activation profile. Complete replacement of islet and stromal macrophages by donor stem cells occurred after lethal irradiation with identical profiles as observed under steady state. The extraordinary plasticity of macrophages within the pancreatic organ and the distinct features imprinted by their anatomical localization sets the base for examining these cells in pathological conditions.
Asunto(s)
Perfilación de la Expresión Génica , Macrófagos/citología , Páncreas/anatomía & histología , Páncreas/citología , Animales , Animales Recién Nacidos , Antígenos CD11/genética , Proliferación Celular , Dieta , Islotes Pancreáticos , Leucocitos/citología , Factor Estimulante de Colonias de Macrófagos/genética , Factor Estimulante de Colonias de Macrófagos/metabolismo , Macrófagos/fisiología , Ratones Endogámicos C57BL , Ratones Mutantes , Páncreas/embriología , Receptores CCR2/genética , Receptores CCR2/metabolismoRESUMEN
Variation in the presentation of hereditary immunodeficiencies may be explained by genetic or environmental factors. Patients with mutations in HOIL1 (RBCK1) present with amylopectinosis-associated myopathy with or without hyper-inflammation and immunodeficiency. We report that barrier-raised HOIL-1-deficient mice exhibit amylopectin-like deposits in the myocardium but show minimal signs of hyper-inflammation. However, they show immunodeficiency upon acute infection with Listeria monocytogenes, Toxoplasma gondii or Citrobacter rodentium. Increased susceptibility to Listeria was due to HOIL-1 function in hematopoietic cells and macrophages in production of protective cytokines. In contrast, HOIL-1-deficient mice showed enhanced control of chronic Mycobacterium tuberculosis or murine γ-herpesvirus 68 (MHV68), and these infections conferred a hyper-inflammatory phenotype. Surprisingly, chronic infection with MHV68 complemented the immunodeficiency of HOIL-1, IL-6, Caspase-1 and Caspase-1;Caspase-11-deficient mice following Listeria infection. Thus chronic herpesvirus infection generates signs of auto-inflammation and complements genetic immunodeficiency in mutant mice, highlighting the importance of accounting for the virome in genotype-phenotype studies.
Asunto(s)
Infecciones por Herpesviridae/inmunología , Infecciones por Herpesviridae/patología , Herpesviridae/fisiología , Síndromes de Inmunodeficiencia/genética , Síndromes de Inmunodeficiencia/virología , Enfermedad Aguda , Animales , Células de la Médula Ósea/citología , Caspasa 1/metabolismo , Compartimento Celular , Enfermedad Crónica , Citrobacter/fisiología , Citocinas/biosíntesis , Prueba de Complementación Genética , Infecciones por Herpesviridae/virología , Humanos , Inmunidad Innata , Inflamación/patología , Mediadores de Inflamación/metabolismo , Interleucina-6/metabolismo , Listeria monocytogenes/fisiología , Listeriosis/inmunología , Listeriosis/microbiología , Listeriosis/patología , Macrófagos/metabolismo , Ratones , Ratones Noqueados , Mycobacterium tuberculosis/fisiología , Fenotipo , Rhadinovirus/fisiología , Toxoplasma , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
Autoimmune diabetes is characterized by inflammatory infiltration; however, the initiating events are poorly understood. We found that the islets of Langerhans in young nonobese diabetic (NOD) mice contained two antigen-presenting cell (APC) populations: a major macrophage and a minor CD103(+) dendritic cell (DC) population. By 4 weeks of age, CD4(+) T cells entered islets coincident with an increase in CD103(+) DCs. In order to examine the role of the CD103(+) DCs in diabetes, we examined Batf3-deficient NOD mice that lacked the CD103(+) DCs in islets and pancreatic lymph nodes. This led to a lack of autoreactive T cells in islets and, importantly, no incidence of diabetes. Additional examination revealed that presentation of major histocompatibility complex (MHC) class I epitopes in the pancreatic lymph nodes was absent with a partial impairment of MHC class II presentation. Altogether, this study reveals that CD103(+) DCs are essential for autoimmune diabetes development.
Asunto(s)
Antígenos CD/biosíntesis , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Antígenos CD8/biosíntesis , Diabetes Mellitus Tipo 1/inmunología , Cadenas alfa de Integrinas/biosíntesis , Células de Langerhans/inmunología , Proteínas Represoras/genética , Animales , Presentación de Antígeno/inmunología , Autoinmunidad/inmunología , Diabetes Mellitus Tipo 1/genética , Epítopos/biosíntesis , Epítopos/inmunología , Femenino , Antígenos de Histocompatibilidad Clase I/biosíntesis , Antígenos de Histocompatibilidad Clase I/inmunología , Antígenos de Histocompatibilidad Clase II/biosíntesis , Antígenos de Histocompatibilidad Clase II/inmunología , Proteínas de Homeodominio/genética , Inflamación/inmunología , Islotes Pancreáticos/citología , Islotes Pancreáticos/inmunología , Ganglios Linfáticos/citología , Macrófagos/inmunología , Ratones , Ratones Endogámicos NOD , Ratones Noqueados , Páncreas/citología , Linfocitos T/inmunologíaRESUMEN
TH1 and TH17 cells mediate neuroinflammation in experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis. Pathogenic TH cells in EAE must produce the pro-inflammatory cytokine granulocyte-macrophage colony stimulating factor (GM-CSF). TH cell pathogenicity in EAE is also regulated by cell-intrinsic production of the immunosuppressive cytokine interleukin 10 (IL-10). Here we demonstrate that mice deficient for the basic helix-loop-helix (bHLH) transcription factor Bhlhe40 (Bhlhe40(-/-)) are resistant to the induction of EAE. Bhlhe40 is required in vivo in a T cell-intrinsic manner, where it positively regulates the production of GM-CSF and negatively regulates the production of IL-10. In vitro, GM-CSF secretion is selectively abrogated in polarized Bhlhe40(-/-) TH1 and TH17 cells, and these cells show increased production of IL-10. Blockade of IL-10 receptor in Bhlhe40(-/-) mice renders them susceptible to EAE. These findings identify Bhlhe40 as a critical regulator of autoreactive T-cell pathogenicity.
Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Proteínas de Homeodominio/inmunología , Interleucina-10/inmunología , Esclerosis Múltiple/inmunología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Encefalomielitis Autoinmune Experimental/genética , Proteínas de Homeodominio/genética , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Esclerosis Múltiple/genética , Receptores de Interleucina-10/genética , Receptores de Interleucina-10/inmunología , Células TH1/inmunología , Células Th17/inmunologíaRESUMEN
The islets of Langerhans normally contain resident antigen presenting cells (APCs), which in normal conditions are mostly represented by macrophages, with a few dendritic cells (DC). We present here the features of these islet APCs, making the point that they have a supportive function in islet homeostasis. Islet APCs express high levels of major histocompatibility complexes (MHC) molecules on their surfaces and are highly active in antigen presentation in the autoimmune diabetes of the NOD mouse: they do this by presenting peptides derived from molecules of the ß-cells. These APCs also are instrumental in the localization of diabetogenic T cells into islets. The islet APC present exogenous peptides derived from secretory granules of the ß-cell, giving rise to unique peptide-MHC complexes (pMHC) that activate those non-conventional T cells that bypass thymus selection.
Asunto(s)
Presentación de Antígeno/inmunología , Diabetes Mellitus Tipo 1/inmunología , Células Secretoras de Insulina/inmunología , Células Secretoras de Insulina/patología , Islotes Pancreáticos/inmunología , Islotes Pancreáticos/patología , Animales , Presentación de Antígeno/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patología , Homeostasis/genética , Homeostasis/inmunología , Insulina/química , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Vesículas Secretoras/genética , Vesículas Secretoras/inmunología , Vesículas Secretoras/patologíaRESUMEN
Cardiac macrophages are crucial for tissue repair after cardiac injury but are not well characterized. Here we identify four populations of cardiac macrophages. At steady state, resident macrophages were primarily maintained through local proliferation. However, after macrophage depletion or during cardiac inflammation, Ly6c(hi) monocytes contributed to all four macrophage populations, whereas resident macrophages also expanded numerically through proliferation. Genetic fate mapping revealed that yolk-sac and fetal monocyte progenitors gave rise to the majority of cardiac macrophages, and the heart was among a minority of organs in which substantial numbers of yolk-sac macrophages persisted in adulthood. CCR2 expression and dependence distinguished cardiac macrophages of adult monocyte versus embryonic origin. Transcriptional and functional data revealed that monocyte-derived macrophages coordinate cardiac inflammation, while playing redundant but lesser roles in antigen sampling and efferocytosis. These data highlight the presence of multiple cardiac macrophage subsets, with different functions, origins, and strategies to regulate compartment size.
Asunto(s)
Macrófagos/inmunología , Monocitos/fisiología , Miocarditis/inmunología , Miocardio/inmunología , Animales , Presentación de Antígeno , Antígenos Ly/metabolismo , Muerte Celular , Diferenciación Celular , Linaje de la Célula , Células Cultivadas , Desarrollo Fetal , Corazón/embriología , Homeostasis , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Miocitos Cardíacos/inmunología , Fagocitosis , Receptores CCR2/metabolismo , Transcriptoma , Saco Vitelino/citologíaRESUMEN
Although IFN-γ is required for resolution of Listeria monocytogenes infection, the identities of the IFN-γ-responsive cells that initiate the process remain unclear. We addressed this question using novel mice with conditional loss of IFN-γR (IFNGR1). Itgax-cre(+)Ifngr1(f/f) mice with selective IFN-γ unresponsiveness in CD8α(+) dendritic cells displayed increased susceptibility to infection. This phenotype was due to the inability of IFN-γ-unresponsive CD8α(+) dendritic cells to produce the initial burst of IL-12 induced by IFN-γ from TNF-α-activated NK/NKT cells. The defect in early IL-12 production resulted in increased IL-4 production that established a myeloid cell environment favoring Listeria growth. Neutralization of IL-4 restored Listeria resistance in Itgax-cre(+)Ifngr1(f/f) mice. We also found that Itgax-cre(+)Ifngr1(f/f) mice survived infection with low-dose Listeria as the result of a second wave of IL-12 produced by Ly6C(hi) monocytes. Thus, an IFN-γ-driven cascade involving CD8α(+) dendritic cells and NK/NKT cells induces the rapid production of IL-12 that initiates the anti-Listeria response.