Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 119(14): e2111804119, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35353625

RESUMO

The receptor for colony stimulating factor 1 (CSF-1R) is important for the survival and function of myeloid cells that mediate pathology during experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). CSF-1 and IL-34, the ligands of CSF-1R, have similar bioactivities but distinct tissue and context-dependent expression patterns, suggesting that they have different roles. This could be the case in EAE, given that CSF-1 expression is up-regulated in the CNS, while IL-34 remains constitutively expressed. We found that targeting CSF-1 with neutralizing antibody halted ongoing EAE, with efficacy superior to CSF-1R inhibitor BLZ945, whereas IL-34 neutralization had no effect, suggesting that pathogenic myeloid cells were maintained by CSF-1. Both anti­CSF-1 and BLZ945 treatment greatly reduced the number of monocyte-derived cells and microglia in the CNS. However, anti­CSF-1 selectively depleted inflammatory microglia and monocytes in inflamed CNS areas, whereas BLZ945 depleted virtually all myeloid cells, including quiescent microglia, throughout the CNS. Anti­CSF-1 treatment reduced the size of demyelinated lesions and microglial activation in the gray matter. Lastly, we found that bone marrow­derived immune cells were the major mediators of CSF-1R­dependent pathology, while microglia played a lesser role. Our findings suggest that targeting CSF-1 could be effective in ameliorating MS pathology, while preserving the homeostatic functions of myeloid cells, thereby minimizing risks associated with ablation of CSF-1R­dependent cells.


Assuntos
Encefalomielite Autoimune Experimental , Fator Estimulador de Colônias de Macrófagos , Esclerose Múltipla , Animais , Benzotiazóis/farmacologia , Benzotiazóis/uso terapêutico , Sistema Nervoso Central/imunologia , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/imunologia , Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Fator Estimulador de Colônias de Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/imunologia , Células Mieloides/efeitos dos fármacos , Células Mieloides/metabolismo , Ácidos Picolínicos/farmacologia , Ácidos Picolínicos/uso terapêutico , Receptor de Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores
2.
J Vis ; 24(6): 2, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38833255

RESUMO

The spectral locus of unique yellow was determined for flashes of different sizes (<11 arcmin) and durations (<500 ms) presented in and near the fovea. An adaptive optics scanning laser ophthalmoscope was used to minimize the effects of higher-order aberrations during simultaneous stimulus delivery and retinal imaging. In certain subjects, parafoveal cones were classified as L, M, or S, which permitted the comparison of unique yellow measurements with variations in local L/M ratios within and between observers. Unique yellow shifted to longer wavelengths as stimulus size or duration was reduced. This effect is most pronounced for changes in size and more apparent in the fovea than in the parafovea. The observed variations in unique yellow are not entirely predicted from variations in L/M ratio and therefore implicate neural processes beyond photoreception.


Assuntos
Fóvea Central , Estimulação Luminosa , Células Fotorreceptoras Retinianas Cones , Humanos , Estimulação Luminosa/métodos , Células Fotorreceptoras Retinianas Cones/fisiologia , Fóvea Central/fisiologia , Percepção de Cores/fisiologia , Retina/fisiologia , Adulto , Oftalmoscopia/métodos
3.
J Vis ; 23(5): 2, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37133838

RESUMO

When single cones are stimulated with spots of 543-nm light presented against a white background, subjects report percepts that vary between predominately red, white, and green. However, light of the same spectral composition viewed over a large field under normal viewing conditions looks invariably green and highly saturated. It remains unknown what stimulus parameters are most important for governing the color appearance in the transition between these two extreme cases. The current study varied the size, intensity and retinal motion of stimuli presented in an adaptive optics scanning laser ophthalmoscope. Stimuli were either stabilized on target locations or allowed to drift across the retina with the eye's natural motion. Increasing both stimulus size and intensity led to higher likelihoods that monochromatic spots of light were perceived as green, whereas only higher intensities led to increases in perceived saturation. The data also show an interaction between size and intensity, suggesting that the balance between magnocellular and parvocellular activation may be critical factors for color perception. Surprisingly, under the range of conditions tested, color appearance did not depend on whether stimuli were stabilized. Sequential activation of many cones does not appear to drive hue and saturation perception as effectively as simultaneous activation of many cones.


Assuntos
Retina , Células Fotorreceptoras Retinianas Cones , Humanos , Retina/fisiologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Visão Ocular , Percepção de Cores/fisiologia
4.
J Vis ; 23(12): 4, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37801322

RESUMO

The 2-photon effect in vision occurs when two photons of the same wavelength are absorbed by cone photopigment in the retina and create a visual sensation matching the appearance of light close to half their wavelength. This effect is especially salient for infrared light, where humans are mostly insensitive to 1-photon isomerizations and thus any perception is dominated by 2-photon isomerizations. This phenomenon can be made more readily visible using short-pulsed lasers, which increase the likelihood of 2-photon excitation by making photon arrivals at the retina more concentrated in time. Adaptive optics provides another avenue for enhancing the 2-photon effect by focusing light more tightly at the retina, thereby increasing the spatial concentration of incident photons. This article makes three contributions. First, we demonstrate through color-matching experiments that an adaptive optics correction can provide a 25-fold increase in the luminance of the 2-photon effect-a boost equivalent to reducing pulse width by 96%. Second, we provide image-based evidence that the 2-photon effect occurs at the photoreceptor level. Third, we use our results to compute the specifications for a system that could utilize 2-photon vision and adaptive optics to image and stimulate the retina using a single infrared wavelength and reach luminance levels comparable to conventional displays.


Assuntos
Células Fotorreceptoras Retinianas Cones , Visão Ocular , Humanos , Retina
5.
J Immunol ; 204(3): 531-539, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31852750

RESUMO

Multiple sclerosis and experimental autoimmune encephalomyelitis (EAE) are inflammatory diseases of the CNS in which Th17 cells play a major role in the disease pathogenesis. Th17 cells that secrete GM-CSF are pathogenic and drive inflammation of the CNS. IL-9 is a cytokine with pleiotropic functions, and it has been suggested that it controls the pathogenic inflammation mediated by Th17 cells, and IL-9R-/- mice develop more severe EAE compared with wild-type counterparts. However, the underlying mechanism by which IL-9 suppresses EAE has not been clearly defined. In this study, we investigated how IL-9 modulates EAE development. By using mice knockout for IL-9R, we show that more severe EAE in IL-9R-/- mice correlates with increased numbers of GM-CSF+ CD4+ T cells and inflammatory dendritic cells (DCs) in the CNS. Furthermore, DCs from IL-9R-/- mice induced more GM-CSF production by T cells and exacerbated EAE upon adoptive transfer than did wild-type DCs. Our results suggest that IL-9 reduces autoimmune neuroinflammation by suppressing GM-CSF production by CD4+ T cells through the modulation of DCs.


Assuntos
Sistema Nervoso Central/fisiologia , Células Dendríticas/imunologia , Encefalomielite Autoimune Experimental/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interleucina-9/metabolismo , Esclerose Múltipla/imunologia , Células Th17/imunologia , Transferência Adotiva , Animais , Autoimunidade , Células Cultivadas , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Interleucina-9/genética
6.
Blood ; 132(18): 1936-1950, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30018080

RESUMO

The Hermes receptor CD44 is a multifunctional adhesion molecule that plays an essential role in the homing and invasion of neoplastic stem cells in various myeloid malignancies. Although mast cells (MCs) reportedly express CD44, little is known about the regulation and function of this receptor in neoplastic cells in systemic mastocytosis (SM). We found that clonal CD34+/CD38- stem cells, CD34+/CD38+ progenitor cells, and CD117++/CD34- MCs invariably express CD44 in patients with indolent SM (ISM), SM with an associated hematologic neoplasm, aggressive SM, and MC leukemia (MCL). In addition, all human MCL-like cell lines examined (HMC-1, ROSA, and MCPV-1) displayed cytoplasmic and cell-surface CD44. We also found that expression of CD44 in neoplastic MCs depends on RAS-MEK and STAT5 signaling and increases with the aggressiveness of SM. Correspondingly, higher levels of soluble CD44 were measured in the sera of patients with advanced SM compared with ISM or cutaneous mastocytosis and were found to correlate with overall and progression-free survival. To investigate the functional role of CD44, a xenotransplantation model was employed using severe combined immunodeficient (SCID) mice, HMC-1.2 cells, and a short hairpin RNA (shRNA) against CD44. In this model, the shRNA-mediated knockdown of CD44 resulted in reduced MC expansion and tumor formation and prolonged survival in SCID mice compared with HMC-1.2 cells transduced with control shRNA. Together, our data show that CD44 is a RAS-MEK/STAT5-driven MC invasion receptor that correlates with the aggressiveness of SM. Whether CD44 can serve as therapeutic target in advanced SM remains to be determined in forthcoming studies.


Assuntos
Regulação Neoplásica da Expressão Gênica , Receptores de Hialuronatos/genética , Mastocitose Sistêmica/genética , Invasividade Neoplásica/genética , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Proteínas ras/metabolismo , Adulto , Idoso , Animais , Progressão da Doença , Feminino , Humanos , Receptores de Hialuronatos/análise , Masculino , Mastócitos/metabolismo , Mastócitos/patologia , Mastocitose Sistêmica/metabolismo , Mastocitose Sistêmica/patologia , Camundongos Endogâmicos BALB C , Camundongos SCID , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Metástase Neoplásica/genética , Metástase Neoplásica/patologia
7.
Acta Oncol ; 58(7): 967-976, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30994047

RESUMO

Background: Primary CNS lymphoma is a highly aggressive and rare type of extranodal non-Hodgkin lymphoma. Although, new therapeutic approaches have led to improved survival, the management of the disease poses a challenge, practice patterns vary across institutions and countries, and remain ill-defined for vulnerable patient subgroups. Material and Methods: Using information from the Austrian Brain Tumor Registry we followed a population-based cohort of 189 patients newly diagnosed from 2005 to 2010 through various lines of treatment until death or last follow-up (12-31-2016). Prognostic factors and treatment-related data were integrated in a comprehensive survival analysis including conditional survival estimates. Results: We find variable patterns of first-line treatment with increasing use of rituximab and high-dose methotrexate (HDMTX)-based poly-chemotherapy after 2007, paralleled by an increase in median overall survival restricted to patients aged below 70 years. In the entire cohort, 5-year overall survival was 24.4% while 5-year conditional survival increased with every year postdiagnosis. Conclusion: In conclusion, we show that the use of poly-chemotherapy and immunotherapy has disseminated to community practice to a fair extent and survival has increased over time at least in younger patients. Annually increasing conditional survival rates provide clinicians with an adequate and encouraging prognostic measure.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Adolescente , Adulto , Idoso , Áustria/epidemiologia , Neoplasias Encefálicas/mortalidade , Feminino , Seguimentos , Humanos , Linfoma não Hodgkin/mortalidade , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Prognóstico , Intervalo Livre de Progressão , Sistema de Registros/estatística & dados numéricos , Rituximab/uso terapêutico , Análise de Sobrevida , Adulto Jovem
8.
J Vis ; 19(11): 8, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31532470

RESUMO

The study of fixational eye motion has implications for the neural and computational underpinnings of vision. One component of fixational eye motion is tremor, a high-frequency oscillatory jitter reported to be anywhere from ∼11-60 arcseconds in amplitude. In order to isolate the effects of tremor on the retinal image directly and in the absence of optical blur, high-frequency, high-resolution eye traces were collected in six subjects from videos recorded with an adaptive optics scanning laser ophthalmoscope. Videos were acquired while subjects engaged in an active fixation task where they fixated on a tumbling E stimulus and reported changes in its orientation. Spectral analysis was conducted on periods of ocular drift, with all drifts being concatenated together after removal of saccades from the trace. The resultant amplitude spectra showed a slight deviation from the traditional 1/f nature of optical drift in the frequency range of 50-100 Hz, which is indicative of tremor. However, this deviation rarely exceeded 1 arcsecond and the consequent standard deviation of retinal image motion over the tremor band (50-100 Hz) was just over 5 arcseconds. Given such a small amplitude, it is unlikely tremor will contribute in any meaningful way to the visual percept.


Assuntos
Fixação Ocular/fisiologia , Retina/fisiologia , Movimentos Sacádicos/fisiologia , Tremor/fisiopatologia , Visão Ocular/fisiologia , Adaptação Fisiológica/fisiologia , Adulto , Humanos , Movimento (Física) , Orientação Espacial/fisiologia , Gravação em Vídeo
9.
Eur J Haematol ; 101(3): 326-331, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29799642

RESUMO

BACKGROUND: Autologous stem cell transplantation (ASCT) following BEAM (BCNU, etoposide, cytarabine, melphalan) conditioning is standard of care in relapsed low- and high-grade B-cell lymphoma (DLBCL) and other lymphoproliferative disorders, but BCNU is associated with interstitial pneumonia and an increased mortality. A less toxic regimen might improve the outcome of patients with lymphoma after transplantation. OBJECTIVES: We investigated the role of bendamustine replacing BCNU in the BEAM regimen in patients with lymphoma undergoing ASCT. PATIENTS/METHODS: The conditioning regimen BendaEAM consisted of bendamustine, cytarabine, etoposide, and melphalan and was used in patients with Hodgkin's disease (HD) and Non-Hodgkin lymphoma (NHL). RESULTS: Forty-one patients with HD (n = 9) or NHL (n = 32) were consecutively treated with Benda-BEAM replacing BCNU. No pulmonary or renal toxicities occurred, and no patient died related to transplant. After a median follow-up of 55 months, CR rate was 56%, 18 patients (44%) showed progression after a median time of 7 months after transplantation (range: 2-29 months), and 11 patients (24%) have died, all due to lymphoma progression. The 1-, 2-, and 4-year PFS are 73.2%, 58.6%, and 55.6% and the 1-, 2-, and 4-year OS 85.4%, 78.0%, and 72.6%, respectively. CONCLUSION: BendaEAM seems to be feasible with a promising response rate and acceptable toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cloridrato de Bendamustina/administração & dosagem , Transplante de Células-Tronco Hematopoéticas , Linfoma/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carmustina/efeitos adversos , Carmustina/uso terapêutico , Terapia Combinada , Citarabina/efeitos adversos , Citarabina/uso terapêutico , Etoposídeo/efeitos adversos , Etoposídeo/uso terapêutico , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Linfoma/diagnóstico , Linfoma/mortalidade , Masculino , Melfalan/efeitos adversos , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Análise de Sobrevida , Condicionamento Pré-Transplante , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
10.
J Vis ; 18(11): 19, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30372729

RESUMO

Organisms are faced with the challenge of making inferences about the physical world from incomplete incoming sensory information. One strategy to combat ambiguity in this process is to combine new information with prior experiences. We investigated the strategy of combining these information sources in color vision. Single cones in human subjects were stimulated and the associated percepts were recorded. Subjects rated each flash for brightness, hue, and saturation. Brightness ratings were proportional to stimulus intensity. Saturation was independent of intensity, but varied between cones. Hue, in contrast, was assigned in a stereotyped manner that was predicted by cone type. These experiments revealed that, near the fovea, long and middle wavelength sensitive cones produce sensations that can be reliably distinguished on the basis of hue, but not saturation or brightness. Taken together, these observations implicate the high-resolution, color-opponent parvocellular pathway in this low-level visual task.


Assuntos
Visão de Cores/fisiologia , Fóvea Central , Células Fotorreceptoras Retinianas Cones/fisiologia , Adulto , Cor , Feminino , Humanos , Masculino , Limiar Sensorial
11.
Br J Haematol ; 166(3): 375-81, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24749757

RESUMO

Combinations of agents may improve outcomes among elderly acute myeloid leukaemia (AML) and high-risk myelodysplastic syndrome (MDS) patients. We performed an adaptive phase I/II trial for newly-diagnosed AML or high-risk MDS patients aged ≥50 years using a Bayesian approach to determine whether 1 of 3 doses of bendamustine (45, 60, 75 mg/m(2) days 1-3), together with idarubicin (12 mg/m(2) days 1-2), might provide a complete response (CR) rate ≥40% with <30% grade 3-4 non-haematological toxicity. We treated 39 patients (34 AML; five MDS with >10% marrow blasts; median age 73 years). None of the three bendamustine doses in combination with idarubicin met the required CR and toxicity rates; the 75 mg/m(2) dose because of excess toxicity (two of three patients) and the 60 mg/m(2) dose because of low efficacy (CR rate 10/33), although no grade 3-4 non-haematological toxicity was seen at this dose. Median survival was 7·2 months. All patients began treatment as outpatients but hospitalization was required in 90% (35/39). Although we did not find a dose of bendamustine combined with idarubicin that would provide a CR rate of >40% with acceptable toxicity, bendamustine may have activity in AML/MDS patients, suggesting its addition to other regimens may be warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Síndromes Mielodisplásicas/tratamento farmacológico , Pacientes Ambulatoriais , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cloridrato de Bendamustina , Estudos de Coortes , Feminino , Hospitalização , Humanos , Idarubicina/administração & dosagem , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Compostos de Mostarda Nitrogenada/administração & dosagem , Resultado do Tratamento
12.
J Neuroimmunol ; 362: 577778, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34814011

RESUMO

D-mannose (D-m) is a glucose epimer found in natural products, especially fruits. In mouse models of diabetes and airway inflammation, D-m supplementation via drinking water attenuated pathology by modifying cellular energy metabolism, leading to the activation of latent transforming growth factor beta (TGF-ß), which in turn induced T regulatory cells (Tregs). Given that Tregs are important in controlling neuroinflammation in experimental autoimmune encephalomyelitis (EAE) and likely in multiple sclerosis (MS), we hypothesized that D-m could also suppress EAE. We found that D-m delayed disease onset and reduced disease severity in two models of EAE. Importantly, D-m treatment prevented relapses in a relapsing-remitting model of EAE, which mimics the most common clinical manifestation of MS. EAE suppression was accompanied by increased frequency of CD4+FoxP3+ Tregs in the central nervous system, suggesting that EAE suppression resulted from Treg cell induction by D-m. These findings suggest that D-m has the potential to be a safe and low-cost complementary therapy for MS.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Manose/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Administração Oral , Animais , Feminino , Camundongos
13.
Blood Adv ; 6(23): 5980-5994, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36206195

RESUMO

GATA-binding factor 1 (GATA1) is a transcription factor that governs the development and function of multiple hematopoietic cell lineages. GATA1 is expressed in hematopoietic stem and progenitor cells (HSPCs) and is essential for erythroid lineage commitment; however, whether it plays a role in hematopoietic stem cell (HSC) biology and the development of myeloid cells, and what that role might be, remains unclear. We initially set out to test the role of eosinophils in experimental autoimmune encephalomyelitis (EAE), a model of central nervous system autoimmunity, using mice lacking a double GATA-site (ΔdblGATA), which lacks eosinophils due to the deletion of the dblGATA enhancer to Gata1, which alters its expression. ΔdblGATA mice were resistant to EAE, but not because of a lack of eosinophils, suggesting that these mice have an additional defect. ΔdblGATA mice with EAE had fewer inflammatory myeloid cells than the control mice, suggesting that resistance to EAE is caused by a defect in myeloid cells. Naïve ΔdblGATA mice also showed reduced frequency of CD11b+ myeloid cells in the blood, indicating a defect in myeloid cell production. Examination of HSPCs revealed fewer HSCs and myeloid cell progenitors in the ΔdblGATA bone marrow (BM), and competitive BM chimera experiments showed a reduced capacity of the ΔdblGATA BM to reconstitute immune cells, suggesting that reduced numbers of ΔdblGATA HSPCs cause a functional deficit during inflammation. Taken together, our data show that GATA1 regulates the number of HSPCs and that reduced GATA1 expression due to dblGATA deletion results in a diminished immune response following the inflammatory challenge.


Assuntos
Fator de Transcrição GATA1 , Células-Tronco Hematopoéticas , Doenças Neuroinflamatórias , Animais , Camundongos , Diferenciação Celular , Regulação da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Fator de Transcrição GATA1/metabolismo
14.
J Clin Invest ; 132(22)2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36136587

RESUMO

Astrocytes are highly heterogeneous in their phenotype and function, which contributes to CNS disease, repair, and aging; however, the molecular mechanism of their functional states remains largely unknown. Here, we show that activation of sirtuin 1 (SIRT1), a protein deacetylase, played an important role in the detrimental actions of reactive astrocytes, whereas its inactivation conferred these cells with antiinflammatory functions that inhibited the production of proinflammatory mediators by myeloid cells and microglia and promoted the differentiation of oligodendrocyte progenitor cells. Mice with astrocyte-specific Sirt1 knockout (Sirt1-/-) had suppressed progression of experimental autoimmune encephalomyelitis (EAE), an animal model of CNS inflammatory demyelinating disease. Ongoing EAE was also suppressed when Sirt1 expression in astrocytes was diminished by a CRISPR/Cas vector, resulting in reduced demyelination, decreased numbers of T cells, and an increased rate of IL-10-producing macrophages and microglia in the CNS, whereas the peripheral immune response remained unaffected. Mechanistically, Sirt1-/- astrocytes expressed a range of nuclear factor erythroid-derived 2-like 2 (Nfe2l2) target genes, and Nfe2l2 deficiency shifted the beneficial action of Sirt1-/- astrocytes to a detrimental one. These findings identify an approach for switching the functional state of reactive astrocytes that will facilitate the development of astrocyte-targeting therapies for inflammatory neurodegenerative diseases such as multiple sclerosis.


Assuntos
Astrócitos , Encefalomielite Autoimune Experimental , Sirtuína 1 , Animais , Camundongos , Astrócitos/enzimologia , Astrócitos/patologia , Autoimunidade , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/patologia , Camundongos Endogâmicos C57BL , Fenótipo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Camundongos Knockout
15.
Biol Blood Marrow Transplant ; 17(1): 133-40, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20601032

RESUMO

Although imatinib has become standard first-line therapy in chronic myelogenous leukemia (CML), allogeneic hematopoietic stem cell transplantation (HSCT) is still considered to be an important treatment alternative for patients with drug resistance or advanced disease. We retrospectively analyzed 175 adult CML patients who underwent HSCT at our institution between 1983 and 2007, with the aim to compare outcomes in patient subgroups and to identify prognostic variables. The median follow-up was 65 months. The probability of overall survival (OS) for all patients was 62%, with a significant improvement seen in the imatinib-era (2001-2007) compared to previous time periods (P <.05). Furthermore, a significantly better outcome for patients with chronic phase CML compared to patients with accelerated or blast phase could be observed (P < .05). Cumulative incidence (CI) of treatment-related mortality (TRM) was 9.7% at 100 days and 1 year after HSCT. CI of relapse was 5% at 1 year and 7.5% at 3 years after HSCT. Post-HSCT outcome was not influenced by pretreatment therapy with imatinib, donor type, or a conditioning regimen with total body irradiation (TBI). These data confirm earlier observations and suggest that allogeneic HSCT is still an important treatment option for high-risk patients with CML, and should thus remain an integral component in current and future treatment algorithms.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas/tendências , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Adulto , Benzamidas , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Masculino , Pessoa de Meia-Idade , Piperazinas/uso terapêutico , Prognóstico , Pirimidinas/uso terapêutico , Recidiva , Estudos Retrospectivos , Taxa de Sobrevida , Condicionamento Pré-Transplante/métodos , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
16.
Int Arch Allergy Immunol ; 156(3): 259-66, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21720171

RESUMO

BACKGROUND: Expression of allergens in human cells is a prerequisite for the development of antigen-specific cell therapy in IgE-mediated allergy. We developed a strategy how the clinically relevant major grass pollen allergen Phl p 5 can be efficiently secreted or expressed on the surface of human cells with preserved allergenic activity. METHODS: The cDNA of Phl p 5 was fused to a leader peptide with or without a transmembrane domain and both constructs were ligated into a mammalian expression vector. Transfection of these plasmids into human cells resulted in a membrane-anchored or secreted version of Phl p 5, respectively, as determined by ELISA or flow cytometric analysis. RESULTS: Both the secreted and membrane-anchored Phl p 5 proteins bound IgE from allergic patients in an immunoblot assay and induced specific histamine release and CD203c upregulation in basophils of grass pollen-allergic patients. Proliferation of peripheral blood mononuclear cells from Phl p 5-allergic individuals was induced upon stimulation with both variants of Phl p 5 expressed in human cells similar to recombinant Phl p 5. CONCLUSIONS: Secreted and membrane-anchored Phl p 5 expressed in human cells preserved B cell as well as T cell epitopes and may be used to develop and test various cell-based strategies for allergen-specific immunomodulation and to delineate the tolerance mechanisms involved therein.


Assuntos
Alérgenos/imunologia , Antígenos de Superfície/imunologia , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Proteínas de Membrana/imunologia , Proteínas de Plantas/imunologia , Ribonucleases/imunologia , Alérgenos/biossíntese , Alérgenos/genética , Antígenos de Plantas , Antígenos de Superfície/biossíntese , Antígenos de Superfície/genética , Vetores Genéticos , Células HEK293 , Humanos , Hipersensibilidade Imediata/imunologia , Imunoglobulina E/imunologia , Imunoglobulina E/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Plantas/imunologia , Plantas/metabolismo , Poaceae/imunologia , Pólen/química , Pólen/imunologia , Pólen/metabolismo , Ribonucleases/biossíntese , Ribonucleases/genética , Transfecção
17.
Vision Res ; 188: 85-95, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34293614

RESUMO

In anomalous trichromacy, the color signals available from comparing the activities of the two classes of cone sensitive in the medium and long wavelength parts of the spectrum are much reduced from those available in normal trichromacy, and color discrimination thresholds along the red-green axis are correspondingly elevated. Yet there is evidence that suprathreshold color perception is relatively preserved; this has led to the suggestion that anomalous trichromats post-receptorally amplify their impoverished red-green signals. To test this idea, we measured chromatic discrimination from white and from saturated red and green pedestals. If there is no post-receptoral compensation, the anomalous trichromat's loss of chromatic contrast will apply equally to the pedestal and to the test color. Coupled with a compressively nonlinear neural representation of saturation, this means that a given pedestal contrast will cause a smaller than normal modulation of discrimination sensitivity. We examined cases where chromatic pedestals impair the color discrimination of normal trichromatic observers. As predicted, anomalous observers experienced less impairment than normal trichromats, though they remained less sensitive than normal trichromats. Although the effectiveness of chromatic pedestals in impairing color discrimination was less for anomalous than for normal trichromats, the chromatic pedestals were more effective for anomalous observers than would be expected if the anomalous post-receptoral visual system were the same as in normal trichromacy; the hypothesis of zero compensation can be rejected. This might suggest that the effective contrast of the pedestal is post-receptorally amplified. But on closer analysis, the results do not support candidate simple models involving post-receptoral compensation either.


Assuntos
Defeitos da Visão Cromática , Cor , Percepção de Cores , Testes de Percepção de Cores , Humanos , Células Fotorreceptoras Retinianas Cones
18.
Front Immunol ; 12: 679498, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149716

RESUMO

IFN-ß has been the treatment for multiple sclerosis (MS) for almost three decades, but understanding the mechanisms underlying its beneficial effects remains incomplete. We have shown that MS patients have increased numbers of GM-CSF+ Th cells in circulation, and that IFN-ß therapy reduces their numbers. GM-CSF expression by myelin-specific Th cells is essential for the development of experimental autoimmune encephalomyelitis (EAE), an animal model of MS. These findings suggested that IFN-ß therapy may function via suppression of GM-CSF production by Th cells. In the current study, we elucidated a feedback loop between monocytes and Th cells that amplifies autoimmune neuroinflammation, and found that IFN-ß therapy ameliorates central nervous system (CNS) autoimmunity by inhibiting this proinflammatory loop. IFN-ß suppressed GM-CSF production in Th cells indirectly by acting on monocytes, and IFN-ß signaling in monocytes was required for EAE suppression. IFN-ß increased IL-10 expression by monocytes, and IL-10 was required for the suppressive effects of IFN-ß. IFN-ß treatment suppressed IL-1ß expression by monocytes in the CNS of mice with EAE. GM-CSF from Th cells induced IL-1ß production by monocytes, and, in a positive feedback loop, IL-1ß augmented GM-CSF production by Th cells. In addition to GM-CSF, TNF and FASL expression by Th cells was also necessary for IL-1ß production by monocyte. IFN-ß inhibited GM-CSF, TNF, and FASL expression by Th cells to suppress IL-1ß secretion by monocytes. Overall, our study describes a positive feedback loop involving several Th cell- and monocyte-derived molecules, and IFN-ß actions on monocytes disrupting this proinflammatory loop.


Assuntos
Autoimunidade , Comunicação Celular , Interferon beta/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Animais , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Autoimunidade/efeitos dos fármacos , Comunicação Celular/genética , Comunicação Celular/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças/imunologia , Encefalomielite Autoimune Experimental/etiologia , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Interferon beta/farmacologia , Camundongos , Camundongos Knockout , Monócitos/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos
19.
Invest Ophthalmol Vis Sci ; 61(4): 42, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32343782

RESUMO

Purpose: To study cone structure and function in patients with retinitis pigmentosa (RP) owing to mutations in rhodopsin (RHO), expressed in rod outer segments, and mutations in the RP-GTPase regulator (RPGR) gene, expressed in the connecting cilium of rods and cones. Methods: Four eyes of 4 patients with RHO mutations, 5 eyes of 5 patients with RPGR mutations, and 4 eyes of 4 normal subjects were studied. Cone structure was studied with confocal and split-detector adaptive optics scanning laser ophthalmoscopy (AOSLO) and spectral-domain optical coherence tomography. Retinal function was measured using a 543-nm AOSLO-mediated adaptive optics microperimetry (AOMP) stimulus. The ratio of sensitivity to cone density was compared between groups using the Wilcoxon rank-sum test. Results: AOMP sensitivity/cone density in patients with RPGR mutations was significantly lower than normal (P < 0.001) and lower than patients with RHO mutations (P < 0.015), whereas patients with RHO mutations were similar to normal (P > 0.9). Conclusions: Retinal sensitivity/cone density was lower in patients with RPGR mutations than normal and lower than patients with RHO mutations, perhaps because cones express RPGR and degenerate primarily, whereas cones in eyes with RHO mutations die secondary to rod degeneration. High-resolution microperimetry can reveal differences in cone degeneration in patients with different forms of RP.


Assuntos
Proteínas do Olho/genética , Células Fotorreceptoras Retinianas Cones/patologia , Retinose Pigmentar/diagnóstico por imagem , Retinose Pigmentar/genética , Rodopsina/genética , Tomografia de Coerência Óptica/métodos , Adulto , Fatores Etários , Estudos de Casos e Controles , Eletrorretinografia/métodos , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Mutação/genética , Oftalmoscopia/métodos , Medição de Risco , Polarimetria de Varredura a Laser/métodos , Fatores Sexuais , Estatísticas não Paramétricas , Adulto Jovem
20.
Brain Sci ; 10(6)2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32516999

RESUMO

Multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) are neuroinflammatory diseases of the central nervous system (CNS), where leukocytes and CNS resident cells play important roles in disease development and pathogenesis. The antimalarial drug chloroquine (CQ) has been shown to suppress EAE by modulating dendritic cells (DCs) and Th17 cells. However, the mechanism of action by which CQ modulates EAE is far from being elucidated. Here, we comprehensively analyzed the CNS of CQ and PBS-treated EAE mice to identify and characterize the cells that are affected by CQ. Our results show that leukocytes are largely modulated by CQ and have a reduction in the expression of inflammatory markers. Intriguingly, CQ vastly modulated the CNS resident cells astrocytes, oligodendrocytes (OLs) and microglia (MG), with the latter producing IL-10 and IL-12p70. Overall, our results show a panoramic view of the cellular components that are affect by CQ and provide further evidence that drug repurposing of CQ will be beneficial to MS patients.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA