RESUMEN
Stroke is the leading cause of adult disability. Recovery of function after stroke involves signaling events that are mediated by cAMP and cGMP pathways, such as axonal sprouting, neurogenesis, and synaptic plasticity. cAMP and cGMP are degraded by phosphodiesterases (PDEs), which are differentially expressed in brain regions. PDE10A is highly expressed in the basal ganglia/striatum. We tested a novel PDE10A inhibitor (TAK-063) for its effects on functional recovery. Stroke was produced in mice in the cortex or the striatum. Behavioral recovery was measured to 9 weeks. Tissue outcome measures included analysis of growth factor levels, angiogenesis, neurogenesis, gliogenesis, and inflammation. TAK-063 improved motor recovery after striatal stroke in a dose-related manner, but not in cortical stroke. Recovery of motor function correlated with increases in striatal brain-derived neurotrophic factor. TAK-063 treatment also increased motor system axonal connections. Stroke affects distinct brain regions, with each comprising different cellular and molecular elements. Inhibition of PDE10A improved recovery of function after striatal but not cortical stroke, consistent with its brain localization. This experiment is the first demonstration of brain region-specific enhanced functional recovery after stroke, and indicates that differential molecular signaling between brain regions can be exploited to improve recovery based on stroke subtype.
Asunto(s)
Hidrolasas Diéster Fosfóricas , Accidente Cerebrovascular , Animales , Encéfalo/metabolismo , Cuerpo Estriado/metabolismo , Ratones , Hidrolasas Diéster Fosfóricas/metabolismo , Recuperación de la Función , Accidente Cerebrovascular/tratamiento farmacológicoRESUMEN
BACKGROUND: Chronic Lung Allograft Dysfunction (CLAD) is the main limitation to long-term survival after lung transplantation. Although CLAD is usually not responsive to treatment, earlier identification may improve treatment prospects. METHODS: In a nested case control study, 1-year post transplant surveillance bronchoalveolar lavage (BAL) fluid samples were obtained from incipient CLAD (n = 9) and CLAD free (n = 8) lung transplant recipients. Incipient CLAD cases were diagnosed with CLAD within 2 years, while controls were free from CLAD for at least 4 years following bronchoscopy. Transcription profiles in the BAL cell pellets were assayed with the HG-U133 Plus 2.0 microarray (Affymetrix). Differential gene expression analysis, based on an absolute fold change (incipient CLAD vs no CLAD) >2.0 and an unadjusted p-value ≤0.05, generated a candidate list containing 55 differentially expressed probe sets (51 up-regulated, 4 down-regulated). RESULTS: The cell pellets in incipient CLAD cases were skewed toward immune response pathways, dominated by genes related to recruitment, retention, activation and proliferation of cytotoxic lymphocytes (CD8+ T-cells and natural killer cells). Both hierarchical clustering and a supervised machine learning tool were able to correctly categorize most samples (82.3% and 94.1% respectively) into incipient CLAD and CLAD-free categories. CONCLUSIONS: These findings suggest that a pathobiology, similar to AR, precedes a clinical diagnosis of CLAD. A larger prospective investigation of the BAL cell pellet transcriptome as a biomarker for CLAD risk stratification is warranted.
Asunto(s)
Líquido del Lavado Bronquioalveolar/citología , Rechazo de Injerto/genética , Trasplante de Pulmón/efectos adversos , Estudios de Casos y Controles , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de OligonucleótidosRESUMEN
Idiopathic pulmonary fibrosis is a fatal lung disease with a median survival of 2 to 5 years. A decade of studies has downplayed inflammation contributing to its pathogenesis. However, these studies preceded the discovery of regulatory T cells (Tregs) and all of their functions. On the basis of human studies demonstrating Tregs can decrease graft-versus-host disease and vasculitides, there is consideration of their use to treat idiopathic pulmonary fibrosis. We hypothesized that Treg therapy would attenuate the fibroplasia involved in a preclinical murine model of pulmonary fibrosis. IL-2 complex was used in vivo to expand CD4(+)CD25(hi)Foxp3(+) cells in the lung during intratracheal bleomycin challenge; however, this unexpectedly led to an increase in lung fibrosis. More important, this increase in fibrosis was a lymphocyte-dependent process. We corroborated these results using a CD4(+)CD25(hi)Foxp3(+) cellular-based therapy. Mechanistically, we demonstrated that CD4(+)CD25(hi)Foxp3(+) cells undergo alterations during bleomycin challenge and the IL-2 complex had no effect on profibrotic (eg, transforming growth factor-ß) or type 17 immune response cytokines; however, there was a marked down-regulation of the type 1 and augmentation of the type 2 immune response cytokines from the lungs. Collectively, our animal studies show that a specific lung injury can induce Treg alterations, which can augment pulmonary fibrosis.
Asunto(s)
Fibrosis Pulmonar Idiopática/inmunología , Linfocitos T Reguladores/inmunología , Traslado Adoptivo , Animales , Antibióticos Antineoplásicos/toxicidad , Bleomicina/toxicidad , Modelos Animales de Enfermedad , Femenino , Citometría de Flujo , Fibrosis Pulmonar Idiopática/inducido químicamente , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Reacción en Cadena en Tiempo Real de la Polimerasa , Subgrupos de Linfocitos T/inmunologíaAsunto(s)
Envejecimiento , Infecciones Comunitarias Adquiridas/etiología , Neumonía Neumocócica/etiología , Streptococcus pneumoniae/patogenicidad , Factores de Edad , Anciano , Envejecimiento/inmunología , Infecciones Comunitarias Adquiridas/inmunología , Infecciones Comunitarias Adquiridas/microbiología , Susceptibilidad a Enfermedades , Humanos , Pulmón/inmunología , Pulmón/microbiología , Fagocitosis , Neumonía Neumocócica/inmunología , Neumonía Neumocócica/microbiología , Medición de Riesgo , Factores de Riesgo , Bazo/inmunología , Bazo/microbiología , Streptococcus pneumoniae/inmunología , Linfocitos T/inmunología , Linfocitos T/microbiologíaRESUMEN
Marginal zones (MZs) are architecturally organized for clearance of and rapid response against blood-borne Ags entering the spleen. MZ macrophages (MZMs) and MZ B cells are particularly important in host defense against T-independent pathogens and may be crucial for the prevention of diseases, such as streptococcal pneumonia, that are devastating in older patients. Our objective was to determine whether there are changes in the cellular components of the MZ between old and young mice. Using immunocytochemistry and a blinded scoring system, we observed gross architectural changes in the MZs of old mice, including reduction in the abundance of MZMs surrounding the MZ sinus as well as disruptions in positioning of mucosal addressin cell adhesion molecule 1 (MAdCAM-1)(+) sinus lining cells and metallophilic macrophages. Loss of frequency of MZMs was corroborated by flow cytometry. A majority of old mice also showed reduced frequency of MZ B cells, which correlated with decreased abundance of MZM in individual old mice. The spleens of old mice showed less deposition of intravenously injected dextran particles within the MZ, likely because of the decreased frequency in MZMs, because SIGN-R1 expression was not reduced on MZM from old mice. The phagocytic ability of individual MZMs was examined using Staphylococcus aureus bioparticles, and no differences in phagocytosis were found between macrophages from young or old spleens. In summary, an anatomical breakdown of the MZ occurs in advanced age, and a reduction in frequency of MZM may affect the ability of the MZM compartment to clear blood-borne Ags and mount proper T-independent immune responses.
Asunto(s)
Envejecimiento/inmunología , Envejecimiento/patología , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/patología , Macrófagos/inmunología , Macrófagos/patología , Bazo/inmunología , Bazo/patología , Factores de Edad , Envejecimiento/metabolismo , Animales , Antígenos/metabolismo , Subgrupos de Linfocitos B/metabolismo , Adhesión Celular/inmunología , Recuento de Células , Femenino , Inmunohistoquímica , Linfopenia/inmunología , Linfopenia/metabolismo , Linfopenia/patología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos BALB C , Bazo/metabolismoRESUMEN
Studies in aged mice show that the architecture of B-cell areas appears disrupted and that newly made B cells fail to incorporate into the spleen. These observations may reflect altered migration of immature and mature B cells. Using adoptive transfer, we tested the effect of the aged microenvironment and the intrinsic ability of donor B cells from aged mice to migrate to spleens of intact hosts. Spleens of aged recipients were deficient in attracting young or old donor immature B cells. In contrast, immature and mature B cells maintained an intrinsic ability to migrate to young recipient spleens, except that as the aged immature B cells matured, fewer appeared to enter the recirculating pool. CXCL13 protein, which is necessary for the organization of B-cell compartments, was elevated with age and differences in CXCL13 distribution were apparent. In aged spleens, CXCL13 appeared less reticular, concentrated in patches throughout the follicles, and notably reduced in the MAdCAM-1(+) marginal reticular cells located at the follicular edge. Despite these differences, the migration of young donor follicular B cells into the spleens of old mice was not impacted; whereas, migration of young donor marginal zone B cells was reduced in aged recipients. Finally, the aged bone marrow microenvironment attracted more donor mature B cells than did the young marrow. Message for CXCL13 was not elevated in the marrow of aged mice. These results suggest that the aged splenic microenvironment affects the migration of immature B cells more than mature follicular B cells.
Asunto(s)
Envejecimiento/inmunología , Subgrupos de Linfocitos B/metabolismo , Quimiocina CXCL13/metabolismo , Células Precursoras de Linfocitos B/metabolismo , Bazo/metabolismo , Traslado Adoptivo , Animales , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/patología , Médula Ósea/metabolismo , Médula Ósea/patología , Moléculas de Adhesión Celular/biosíntesis , Diferenciación Celular , Movimiento Celular/fisiología , Quimiocina CXCL13/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Mucoproteínas , Células Precursoras de Linfocitos B/inmunología , Células Precursoras de Linfocitos B/patología , Bazo/inmunología , Bazo/patologíaRESUMEN
OBJECTIVE: The aged population is at a higher risk of mortality as a result of complications of injury or infection, such as acute lung injury. The objective of this study was to analyze pulmonary inflammatory responses in young and aged mice after administration of lipopolysaccharide. DESIGN: Prospective, controlled laboratory study. SETTING: Animal resource facilities and research laboratory. SUBJECTS: Young (2-3 months old) and aged (18-20 months old) female BALB/c mice. INTERVENTIONS: Animals received intraperitoneal injection of lipopolysaccharide derived from Pseudomonas aeruginosa. Control mice received saline alone. After 24 hrs, mice were killed. Pulmonary neutrophil infiltration was assessed histologically and by myeloperoxidase activity. Pulmonary levels of the CXC chemokines, monocyte inflammatory protein-2 and KC, and cytokines, tumor necrosis factor-alpha and interleukin-1beta, were assessed by enzyme-linked immunosorbent assay. MEASUREMENTS AND MAIN RESULTS: Lungs of aged mice given lipopolysaccharide showed a six-fold higher neutrophil infiltration and three-fold higher level of myeloperoxidase activity than lungs of young mice given lipopolysaccharide. Pulmonary levels of monocyte inflammatory protein-2 and KC were significantly higher in the lungs of aged mice given lipopolysaccharide, compared with younger mice. Levels of tumor necrosis factor-alpha and interleukin-1beta in the lung were analyzed as well. After lipopolysaccharide treatment, there was no difference in the level of tumor necrosis factor-alpha in lungs of young and aged animals, but interleukin-1beta was two-fold higher in the lungs of the aged group. These data suggest that at this time point, interleukin-1beta may contribute to the higher production of CXC chemokines observed in lungs of aged mice vs. young mice receiving lipopolysaccharide. CONCLUSIONS: The hyperreactive systemic inflammatory response seen in aged individuals after lipopolysaccharide administration is accompanied by an exacerbated pulmonary inflammatory response, which may contribute to the higher mortality seen in the aged given an inflammatory insult.